The Allan Holdsworth "HARNESS" - Part I 

I wonder if that was Bill Delap he was with. Anyway, yeah it's kinda sad but it's also very subjective. Most (older) guitarists would say GOAT was Van Halen, SRV, Hendrix, Clapton or someone like that. Allan was a true artist - he didn't really care about fame and fortune, only that he could do what he wanted to do. If his music fell neatly into people's music genre categories he might have been more well known. Back in the day it was also hard to get a hold of his music. I first read about Allan in late 80s but I never got to actually hear his music until 1996-ish when I found Metal Fatigue CD in a pawn shop. I was like "yes!" because I kept seeing his name a lot but had no way to hear him. Not until ebay came along could I really acquire any more of his music.

That's awesome... thanks for sharing!

Do you still have your H ii?

Well I'm just a guy that likes to reverse engineer things, and when I see a void I try to fill it. There was very little real info out there about these units, so I wanted to fix that, and shed light on some of Allan's other talents.

I'm always impressed with the tom sholtz mind where he can make something to achieve the exact sounds he wants the build it. So cool

I remember seeing a series on youtube called earth day where allan was being interviewed in the show. The interviewer saw it and allan showed him but didnt go into details about it

Anything he played was going to sound like Allan. That’s probably why he ditched all that and relied on magic stomps in the end.

That's very cool. I would have loved to meet Allan, or to have seen him play. Sounds like he was a good friend to those that knew him on a personal level. Reading between the lines, it seems that he was good natured and got taken advantage of sometimes. I respect that he was a true artist and never lost his vision in the things he wanted to do. I've had to do a lot of detective work to put this thing together. I don't think I would have embarked on this journey if he was still with us.

I believe that is the sound that Allan was chasing - the sound of power section distortion / “transformer saturation”.

ACDC

@@VegasCyclingFreak Transformer Saturators are the best on my daw...before anything

Have a look at Kush Audio's Pusher Compressor...it's Digital Plugin...but has FOUR distinct Metal types...and rhey all sound likr different styles of "Disco Eras" on Drums. Greg Scott the designer talks about that.

Yeah I've always wondered what all the stuff inside these units was about since I first saw the custom one on ebay in 2007. That one is a 2 in 1 type of deal. It was like seeing Wardenclyffe Tower for the first time lol. I've been doing quite a lot of research on the Harness over the last month or so. If I hadn't dug so much I still would not have been able to figure it out. Fortunately I stumbled on some info that Allan himself provided in some pictures I discovered, taken by fans at gigs or at Allan's place. That's what unlocked the mystery! There's a lot more info at my website about all that if you're into technobabble. 😁

Back in the day he had to trail blaze because a lot of the stuff people take for granted today didn't exist. Necessity is the mother of invention as they say...

It's really all just a quest to analyze it and understand it. 😉

I’d love to be able to properly test it. I have to figure out how to do that.

Gee thanks. I really didn't think there would be so much interest in this device... but I can see that many other people are also curious about it!

@@VegasCyclingFreak Fredrik had all kinds of tricks back in the day to achieve Holdsworth’s sound. He even invented a breath controller called the 33 to achieve that sax-like non-percussive attack on his more melodic solos. Way back then, he was using a Mesa 50 Caliber into a Rocktron juice extractor but he and I definitely geeked out over this mystery circuit and some of the reports about it on the gnarly geezer forum a few times back in the day.

@@demesisx Interesting. Was that at the forum at AllanHoldsworth dot com before it got hacked or whatever happened to it? I hung out there sometimes. I know Allan occasionally used a 50 Caliber.

Yeah I think that's the reason why Allan came up with this device, the power tube distortion and OT saturation. He, like me, seemed to not like a super loud amp to get distortion. Back in the day there weren't as many options as we have today in terms of great sounding guitar pedals, etc.

Works that for me with the Yamaha UD Stomp. Allan programmed the first 23 presets, and they are a bit inspirational for sure. I love the depth they have.

Very cool. ha ha I love the "ale tokens" phrase! Haven't heard that one before. Unfortunately I never got to see him play in person or meet him.

Yes, that's the part I am interested in trying to determine - resonant frequency and the frequency response curve. I want to see how close my real world circuit is to what the LTSpice simulation shows. The other thing I determined in some simple tests before I committed to building this thing is that there is also crosstalk between the coils. Not sure what affect that has in the overall scheme of things, but it is a factor to consider.

Thanks. I am happy to hear that you find it interesting.

Cool. Be safe out there. Being a cyclist here in Las Vegas is very deadly lately.

Thanks. I appreciate that.

Hmm... that must be the connection with Rocktron. I've read that the Rocktron Juice Extractor couldn't use inductors in their units because of a patent held by Groove Tubes, which ending up making it a 100% completely different unit than what Allan was building.

@@VegasCyclingFreak has quite successfully connected the dots. 👍🏻😎

Allan Holdsworth's idea. 😉 I'm just building the circuit so I can analyze it. I'll likely never get my hands on a real one because the Holdsworth fanatics that have one will never let it go now that Allan has passed on.

​@@VegasCyclingFreakThe idea to recreate this just based on what you had to go with I still think is pretty cool. Allan was one of a kind and I think he would be giving you a big smile and well done for this.

@@ajlsoundwave Thanks. I like doing this sort of thing once in a while. I've reverse engineered many things over the last 20 years. To quote JFK: "We do these things not because they are easy but because they are hard".

Yes. Hard to say for sure but in the pictures I have of his various units they look like plain steel fender washers to me. I don’t think it’s that big a deal… raises the inductance from 7mH to 10mH. Still within reasonable limits of speaker voice coil inductance. In Suhr unit for example, he uses a 6.8mH inductor. Allan had made himself a unit that had seven 1.5mH chokes in it. It may well be that he used these washers to get the sound he wanted. You can tune them so to speak.

Here there... yeah I came back from the DIY dead. It's only in suggested vids because this particular video has been getting a lot of views and comments. Normally I'm lucky to get 100-200 views on a video before it enters the black hole lol

That's very cool. I think if Allan was my neighbor and were closer in age that we'd be two peas in a pod. He is so much like me in several ways, except when it comes to playing guitar. I didn't get into cycling until 2015, and mountain biking in 2020 after one particular incident where five cyclists were mowed down by a box truck driver on meth. I knew people on that ride, they weren't killed but it messed them up for a while. PTSD I guess. I was a big BMXer as a teenager in the early 80s when Las Vegas was 1/5 the size it is now, and then I didn't touch a bike for nearly 30 years because always busy at work with the massive growth here (consulting engineering). I never ever thought I'd ride a road bike but with all the advances in technology the bikes became a lot more appealing. I don't want to ride on the road much these days because too many cyclists are being killed here. Couple of months ago two teenagers in a stolen car intentionally killed a cyclist, and they were laughing about it while videoing it. Not a great environment for cycling.... but there are lots of places to mountain bike with no worries about people in cars, although very physically demanding in this rocky environment. Oh, did I mention we also have a bad DUI problem here? Anyway, did Allan have any specific favorite racer(s)? I don't recall there being too many Englishmen racing at that time.

@@VegasCyclingFreak Merckx 😁

@@cyclesgoff9768 Ah but of course! Still revered even today. GOAT. I watched Tour De France for first time in 2015, when it was the Team Sky show.

😀Not the point of the video. Does everything on RU-vid have to be some kind of sound demo?!?!

I should just add that Allan Holdsworth *was* the Nicola Tesla of guitar! Indeed, he did an album about him.

@@xanataph Yes I have that album - Wardenclyffe Tower! Thanks for the suggestions... may use some of them down the road. The speaker impedance thing is a bit confusing. I've heard it presented both ways. I ran 8 ohms load (two 16 ohm Celestions) in my Hot Rod Deville designed for pair of 8 ohm Eminence speaker (4 ohms) for 2 years without any trouble, but I also never had it super loud. I don't have a proper amp, or an amp that I am willing to use as a guinea pig to actually test this, so that is my main obstacle at the moment. I have also wondered why not just one inductor, but every one of these I have seen the inside of has the multiple inductor set up. The length of the nichrome wire sections varied, some were skinny and long and some were fatter and shorter. Seems that he was targeting a specific resistance with whatever wire he could get his hands on. You are correct, everything I have heard about these units says that you don't crank everything to 10, if you don't want to fry the OT you use the amp as you normally would but you can do it silently. Apparently, it is also advised that you don't use it for long periods of time, this can also fry an OT (or so I have been told by someone that this happened to). Also, you need to use an isolation transformer on the output. That was one thing I was thinking about building into the circuit. An owner of one of these units told me a story about how he got shocked - he was knocked out by it.

Great "tone" certainly can inspire your playing.

I agree with all of your points. All that an amplifier does is amplify what you are doing with your hands/fingers. I learned this early on from playing acoustic guitar - I can make many different "tones" simply by where I pick the string in relation to the bridge, etc. It's very obvious with certain players that they don't have to rely on equipment because that's not where their sound comes from. They have their own sound and know how to get it with any number of things. As an engineer type, I always found this Harness thing interesting. I thought maybe a few other people might also be interested in it too.

@@VegasCyclingFreak This really is a great video for electronic tweekers and people looking for a little something extra. In the 80s I went through my Bradshaw rack phase. An enormous amount of money spent searching for The Holy Grail. Eventually realizing that it is a never ending escapade and a money pit, I reverted to a few great guitars, a couple of great tube amps and 3 pedals. Reality was and is wonderful when I embraced it. Great channel!

@@Psuperbrain1 Thanks. Yes, I went thru a similar phase but I didn't have to go too hog wild buying tons of expensive stuff to come to that realization. Partly because for a good ten years I was heavily into DIY pedals and amps, so I saved a lot of money compared to buying the real deal. I think back to the days of hearing a sound clip of some person's creation (pre-RU-vid), and I'd be like "wow that sounds great!" - so I'd rush to build it for myself and find that it totally didn't work for me, and I didn't sound anything like that awesome sound clip did lol.

Yes these are the sorts of things I’d like to be able to determine if possible. There will also be crosstalk between the coils.

I think you are correct in that stray capacitance effects will be observable by resonant peaks. My guess is that the capacitive part will be best observed for each inductor. The electrical model will be an inductor with a capacitor in parallel. I will also guess that the bigger "stray" effect will be due to eddy current losses due to the electrical conductivity of any conductors within the magnetic field- Aluminum chassis. The interesting thing about those bolts is that the permeable mass should increase the inductance above the "air coil" measurement, but at some frequency the bolts will cause enough losses that the inductance will drop. Between the capacitive coupling and the eddy losses, impedance will likely drop below the measure DC resistance value. I guess we will have to wait until the exciting conclusion in episode 2! Thanks for posting this information. A.H's tone is a mystery worth unraveling!

@@ethanspaulding6067 Thank for commenting. I don't know that I came to any definite conclusions in part 2. I still have some unanswered questions and a few things that I don't understand. Hopefully with the help of viewers more knowledgeable than myself we can collectively figure it all out!

It's a great mystery to solve! Cheers for all your efforts! Meshuggah are big AH fans as well. Their gear history, at least for lead tones, show's a lot of influence from the man.@@VegasCyclingFreak

Great job on part 2. I would gladly donate one of my heads to crank through it. I'm in Salt Lake City(if that helps). I design magnetics for a living btw. Your efforts were heroic and well documented. It is likely a pretty complex lump sum circuit, so it's no surprise that simulations don't exactly match measurements. Thanks again for sharing your research!@@VegasCyclingFreak

Yes technically, but they start out as air core types. The nichrome wire turns are like an un-stretched spring. Same as what I can see in three examples of Allan’s hand built units.

Yes, but they don't use nichrome wire that is in kW territory. Also they don't use multiple closely mounted inductors with crosstalk, etc. I want to know what affect that has, and to see just how close LTSpice comes to real world in this case. I did same when I reverse engineered/resurrected a dismantled plus ebow about a year ago, although that was more trying to make LTSpice match real world. Anyway, yes I am Allan Holdsworth fan, and a mech engineer type that is curious about certain things. I find the Harness/Juice Extractor interesting and I'll likely never get my hands on one, so this is the next best thing.

Yes, aside from his not of this world guitar playing, Allan was an inventor of sorts. Besides the Harness he invented a thing called the "Fizzbuster", which had to do with one of his favorite pastimes - beer. 😁

Yes, that’s typically what DC resistance is on an 8 ohm speaker… something around 6.0 to 6.5 ohms.

I had that thought. If I had to make many of them that’s how I’d do it.

According to someone who knew Allan very well, it was kinda designed to be used with a Mesa Boogie "turned up to 6." Some of the pics in my video he is using it with a Burman Pro 501 (chassis removed from the cabinet). The Burman Pro 501 is apparently "the English Mesa Boogie" but it's not a copy of a Boogie. I never heard of them before but they seem to be pretty cool little amps. This was 1990 during Level 42 recordings.

It's not coated Nichrome wire as far as I can tell. Don't know that it matters too much, it's more about its current handling capability. It can very easily handle a few amps. It does relax after I wind it so most of the turns have a small space between them. This wire is designed to get red hot, for use in things like radiant heaters and the like. The seven inductors also provide series some resistance. I think it's OK. Not sure about the aluminum vs steel baseplate. It seems they would have roughly the same affect, but steel probably is a little more effective. I was debating with someone else about that baseplate before I started the project. Was a split between it's aluminum and it's galvanized sheet metal. I don't know that I need to have an amp for the next test that I want to do but it would be the easiest way to do it. My Fenders want a 4 ohm load and I don't want to risk anything with the Seymour Duncan Convertible as that OT is quite literally irreplaceable. I'll figure something out. Trying not to spend a lot of money... the cost of living here in Vegas is ridiculous lately.

@@VegasCyclingFreak I remember those Convertible Duncan amps from when I was a teenager working at a small music store. I thought those were really cool and was wondering about them recently. I bet they are rare.

@@jeffhacker3323 Not as many of them around as there used to be. I reverse engineered a lot of things associated with that amp around 2003. I made several of the preamp modules, and I generated PCB layouts for all of the DIY friendly preamp modules. There were only a few that were a little beyond DIY capability. The Convertible really is a great tone machine and could be made to sound like almost any amp. I think if it were introduced today it could have been done a lot better in terms of preamp module interface and overall reliability. The technology at the time kind of limited what it could be.

I found a schematic for the Weber units. Interesting implementation and concept they have there. Big wire wound 50 watt rheostats & ceramic resistors (in some units) with a "voice coil motor". In theory would be most like an actual speaker. It would be interesting to do a shoot out with all these various devices currently on the market to see if there really is a noticeable audible difference between them.

I'm just going off pictures of the nichrome wires in Allan's units. They look like almost like a giant round wound guitar string. Appears to be no gaps in between each coil. The 1 mH inductors are from Parts Express, 20 gage enameled wire rated for 200 watts.

Thanks for speedy reply, happy new year🙂

Yes the coils will interact with each other. With multiple simultaneous frequencies I bet it would get very interesting. I don't have a way to test for that ATM. Once the nichrome gets up to temp it's probably stable. The resistance will change with temperature. Wouldn't be anything real drastic but it will change as it heats up. Hmm... that gives me an idea for another experiment.

I took a look at your analysis and I think you are comparing it wrong. This device does not replicate the freq response of the speaker just the impedance of it. You have to plot resistance, (V/I) on Lt spice and compare it to the impedance of a speaker that is usually 8 ohms with higher peak at 100hz and high freq. Check Randall Aiken webpage he have some good info on load boxes.

The air core inductors in Allan's units have a bolt/screw fastening them to the metal baseplate, along with the large fender washers. I tried to replicate that as close as possible. Those steel components have a large affect on the inductance - in my case it goes up by 42%. I don't know that an aluminum vs steel baseplate would make much of a difference. I can't determine from the pictures I have if steel or aluminum baseplate was used. One custom unit I have a picture of appears to use aluminum. In either of those cases, the whole thing goes into a steel rack mount case. Allan's own prototypes were in aluminum enclosures (the early ones), and he had a few in steel rack mount enclosures too.

That's very interesting about mass. Thanks for that. I'm toying with building a gainclone amp and found a synergy build that uses 3mm ali big baking tray on a heavy wooden chopping board. The idea being the extra mass,somehow improves the sound staging and reduces the boxiness. I dunno,it sounds kinda cool. And yours is the first input I've come across to do with mass being an issue

Cool. I’m surprised that Allan didn’t mark things on these custom units. Would you be willing to answer some technical questions I have about it?

I always thought that was funny. I just took notes when he told me how to use it. He specked out a Carvin power amp to use with it. @@VegasCyclingFreak

Yes, I've heard that story. Not sure if it's true or not. I've only heard the story told secondhand.

@VegasCyclingFreak I believe she mentioned it on the Unreal Allan Holdsworth Facebook group some time ago. PS: Thanks for all the Seymour Duncan Convertible amp info!

@@TheLexluthier I’ll look there. I joined the group not too long ago. I remember someone relating the story but it wasn’t his daughter.

I found the quote from 6 years ago. I'll leave the person that wrote it anonymous but here it is: I have a funny story about this subject -- Roughly 26 years ago, I had the great fortune of visiting with Allan at his home. Allan was telling me the whole story about his Harness and how it worked, when suddenly, a very young and perturbed Louise Holdsworth stormed into the living room to complain "Dad, you took the coils out of the bathroom heater again and it's cold!" 😃 LOL! Allan was taking out the electrical coils from the bathroom heater to use as power attenuators in his Harness!

Look at the inside of Allan's units... they look same as what I've done here. They're really for the current handling capacity. As my "clone" is built, each inductor has a DC resistance of 0.73 ohms, in addition to the nichrome wire. The nichrome wires avg out to 8 ohms when in circuit. Also, uncoated copper wire is waaay more conductive than the nichrome wire, like dozens of times more conductive so the coils being close together isn't really much of a factor.

It may be that the 1mH inductors were easy to get. If he wanted say only 3 or 4mH, or 7mH, it's not difficult to achieve that. Easily done in 1mH increments, and you can switch them in/out of circuit on the custom units he made. There will also be crosstalk between the coils, which is one thing I wonder about - how that affects the sound. I know some people have tried the speaker voice coil thing and said it sounded like crap. Not surprising to me, considering that the speaker cone is absent. The nichrome wire used is in kW territory, so to me much different than a big ceramic resistor.

A speaker coil would burn up within seconds. It is build to be cooled by speaker movement. So a non moving inductor must be sized to withstand the temperature or with low resistance and the needed resistance added by a dedicated and sufficient resistor.

@@ichbinnutzlos5561 That's a good point. I imagine that it would also depend on how hard you're trying to drive the voice coil... but still wouldn't last long with those tiny wires trying to move that much current. Maybe in theory it could work for 1-5 watt application?

That would be an interesting thing to highlight/figure out. As I understand it, a complete Fizz Buster does not exist anymore. Would like to learn more about that story and the device itself.

@@VegasCyclingFreak Though I made my comment in jest, it would be fascinating to see what is behind it and how it functions (as a beer lover myself, and of course a huge Holdsworth fanatic from a guitar playing perspective). I always love seeing pictures of Allan Holdsworth with a bottle of Sierra Nevada Pale Ale in hand.... as a Brit, I can truly say that I think that it's the most well balanced beer I've ever tasted. Unfiltered, gorgeous floral hop notes, and solid toffee malt backbone - we may have pioneered the IPA and Pale Ale, but you guys certainly mastered it!

@@AJDOLDCHANNELARCHIVE I did a little bit of researching. As of about 5-6 years ago one of Allan's Fizzbusters was still in use somewhere in San Marcos, CA. Apparently Allan went into business with a couple of other people but things changed in the industry so it didn't really take off. Some people say it worked really great!

Someone else suggested that but I don't think they can handle 4-5 amps of current.

I’d say so. I don’t know how long he used it but seems to be at least for a few years, and besides recording with it, he also used it at live shows in early 90s.

Yes I think that speaker box was referred to as "the coffin". I don't have any good pictures of it but you can see some of it in the lower right of this picture: www.diyguitarist.net/Images/HARNESS%20VERSIONS.jpg It was an iso box made out of MDF with a speaker and mic inside. He designed it so he could move aspects of it around to get different recording tones.

That's exactly what it says on the front of the Harness - "Power Amp To Line Level Interface". Allan did use solid state Lab Series L5s for a time but I've also seen many other types of amps behind him. I'm not sure exactly how long he used the Harness in live performances but it was a few years at least.

Yeah that's my experience tells me. I don't want to use this thing, which has a calculated impedance of 10 ohms, with a 4 ohm OT. Seems like that's on the edge of a possible bad outcome.

Celebration of life video--ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-3Lnzc2gespg.html

@@VegasCyclingFreak Thanks!

Allan's unit was not trying to be a speaker simulator. The Harness is basically an output transformer matching network with a line level output across the amp's speaker output, all to get a signal level that might be 40V RMS to line level (1-2 volts). It loads the OT pretty heavily which causes the OT to saturate and the output tubes to work hard. Guitar speaker voice coil inductance typically ranges between 0.1mH & 0.5mH. With 7mH of inductors, which adds up to ten when in circuit, is along the lines of the inductance of an output transformer. I'm not sure what a Mesa Boogie OT would measure but I believe that's kinda what he designed it to be used with, initially anyway.

Not sure which version you are referring to but I imagine it must be the STP-G II with the built-in speaker emulator, because schematic for STP-G has no inductors shown on it. Allan's unit was not trying to be a speaker simulator... if that's what you're getting at. The Harness is basically an output transformer matching network with a line level output across the amp's speaker output, all to get a signal level that might be 40V RMS to line level (1-2 volts).

@@VegasCyclingFreak Yes you are correct, but the schematics, even for the version two unit show no circuitry for the " emulator" section either, in fact it's deliberately left out. Apparently the actual technology, which you correctly call speaker-emulation, is also a reduction to line level signal anyway, and is adjusted by its own separate volume control. The output transformer connections are obviously vital for this to function at any volume level within the power amp section, and although a blanked-out part of the diagrams ( from ,for instance, the Tube amp book), shows no details of the " emulator out-put", my fiend assures me that it uses an inductive process to shape the sound before further filtering. I have recorded with this amp, sitting in the control room with a lead patched between the emulator output and a line level input to the desk, but I found, as have others, that the extensive filtering of the sound acts as a treble cutter when using the emulator output, and I found myself trying to compensate with the desk eq to avoid too dull a sound. As the secrecy of the cicuitry remained, it seems that Pitman licenced Marshall to use the patent on their range of attenuators. However, although their is much made of the tone shaping of the Groove Tubes system, it also still acts as a dynamic power-soak or attenuator for further line-level processing, such as Allan Holdsworth's approach. I'm curious as to who first developed these various systems of attenuation, and who did what first, because as you mention ,they're not all the same. For example, the Tom Schultz power-soaks do nothing to allow impedances to vary, as an output transformer, or inductive interface would do. The Fryette Powerstation is probably the best all-round system, but a but too pricy for me. Thanks for your comment.

@@chrisgmurray3622 Thanks for the info. I don't know who was first with this inductor business. May have been GT but I don't know. Did a patent search and that turned up nothing. May not have been a new idea but maybe first to apply to guitar amp? Your guess is as good as mine. Scholz's "Power Soak" was patented in 1982, but that circuit is literally just a bunch of ceramic resistors, 24 of them, with a rotary switch that provides various levels of attenuation. And there's an impedance switch.

Cool idea but you can't use that arrangement silently.

I’ve heard it presented both ways. I ran Fender 2x12 Hot Rod Deville with 8 ohm speaker load for two years with no problem. It’s designed for 4 ohms. Depends on the amp I think.

@@VegasCyclingFreak there are people who have run half the rated load for years too with extension cabs. my blues jr that i use to own and my fender princeton both have shorting jacks incase the speaker gets unplugged and pretty sure all fender tube amps do so they wont blow an output tranny or worse from no load. higher ohms is only better with a solid state amp. going from 4 to 8ohm load may not be that bad but i would definitely not go any higher. speakers are not resistive loads the impedance changes constantly over the frequency spectrum very quickly.

@@jhue73 Yeah I researched this topic a bit recently. It seems that you can go “one size” up or down but putting 16 ohms on 4 ohm OT isn’t a good idea, or vice versa. Depends on the amp too. Fenders seem to have pretty tough output transformers.

No worries. Everyone has different preferences. I've always loved progressive stuff... grew up listening to that sort music.

Can they handle several amps of current?

@@VegasCyclingFreak I don't know.I just know it's readily available in different gauges and is inexpensive.Vape coils get red hot and last forever.

@@VegasCyclingFreak Toaster wire can.

@@randaji Yes probably so

Many people, including myself, would like to know the answer to that question! I have read from some people that knew him that when he was recording that he would EQ his amp to have the bass be at zero, almost no treble and the high & low mids set to about 5-6. Processing the output of that futher, he "shaved" the treble at 4 kHz. This would have been around the time of "None Too Soon". I think some of it was the pickups he used, they have a resonant frequency. Some of it was his technique, could be in his pick attack. In the case of the Harness, I think the parametric EQs play a role there - he probably had a target frequency and cut the bands adjacent to it to get a focused sound at a certain center frequency. Some people say that you need to boost between 400-600 Hz to get a horn-like sound. I have gotten a similar effect by using a Colorsound inductor-less wah pedal in a box acting as a fixed resonant filter. That actually kind of works for the lead tones.

The more you know. The Holdsworth legend continues. Thank you for posting

@@VegasCyclingFreak thanks for your info. I always do a low cut at 250hz and high cut at around 4kHz or 5kHz (as you said). I never thought of a fixed wah - cool idea that I must try!!

@@bingefeller Works best with something that's a little more mellow. A real "peaky" sounding wah circuit will likely be too much. The Colorsound circuit seems to be a good one to be used in this way.

I’m not sure of the exact EQ curve, but I know for a fact that Holdsworth used a TC Electronics 1140 or 2240 parametric EQ to sculpt the sound out of the harness. I bought one specifically for this purpose.

Yeah I did some of those. Most people ride 50/34 compact cranks with 11-28 or 11-32 cassettes. I use 11/32 cassette and compact cranks for anything with a lot of climbing.

@@VegasCyclingFreak: Are all the bike shops in Summerlin competent at working on Campy stuff? Also, do you prefer riding out to Red Rock or staying on the Beltway bike path more often? Is it common for Summerlin riders to do both Red Rock Loops twice during the week?

@@carbonsnail014 Campagnolo is very rare here. Never met anyone that didn't have Shimano, FSA or SRAM on their bike. I don't really do the loop anymore, too many people but when I did I went right at 6AM on a Friday when no one was there. I do 215 trail sometimes but it's more of an e-bike haven these days unless I am out at like 5AM.

@@VegasCyclingFreak: What other locations are there to ride in the area besides the ones mentioned? Thank you.

@@carbonsnail014 Anywhere you have a bike lane on the street. Las Vegas likes to boast that there’s 400 miles of bike lanes here - all of them are unprotected.

It's my understanding that the Rocktron Juice Extractor is a resistive load with EQ, so it's not passive either. I don't have a full schematic for one but the partial one that I do have has a bunch of opamps, and those need power. I'd love to see the inside of one to verify what exactly is in there... searched for some images of the inside but was unsuccessful in finding any. Allan was apparently never able to dial in a sound that he was happy with on that Rocktron unit.

@@VegasCyclingFreak Oh cool! I cam hook you up with some nice HQ pics of mine! Just tell me where to send em my dude! I actually just tried it out the other day. It's pretty dang cool, but def has a sound, and I could see it either working well, or not depending on what you need. Here's my thoughts on it after using it. So, there are two different tonal options besides the Parametric EQ, and those are, a Response Curve(which has 2 settings), and a button that just says Flat(when engaged), and doesn't say what it is when not engaged, I'll have to look at the manual again, but here's what's interesting. So, they say that the Response Curve options(1/2) are like a speaker response curve, but here's whats funny. For one thing, it sounds like it's a feature they promote for obv when someone wants to run an Amp direct to tape/FOH etc, without a Cab, but the two things that are kinda funny are, 1- If you do want to run a Cab, theres no way to turn the response curves off, because it's just always on response curve 1 or 2, but that said, without a speaker(either a Cab or Cab Sim), it doesn't actually sound like it has a true speaker curve on it, and it's just more of a colouration/pre fixed filter/EQ curve. I feel like rather than being a true speaker emulation, it's more meant to be used in tandem with a Speaker, but the problem is that you can't ever turn it off lol. It's almost like how the Rivera Recording Load Box has a graphic EQ that they say is, or can sort of be used to mimic the different EQ curves of speakers, but It's more for fine shaping rather than taking the place of a Speaker IMO, and though you can use it without a Speaker, and get somewhat more of a useable sound that's a little closer to a Speaker. So whatever those two (non-optional) Response Curves are, I feel like play big time into how this thing sounds. I feel like if there was a way to bypass the 2 Curves fully, it would be not just a better sounding unit, but would just then truly be your AMP/The Loadbox/And your Speaker of choice, but this way, even with your Speaker, those built in Curves are always colouring the sound. Next, there is a 2 position button that just says (out)-Flat, and doesn't say what the In position is, but basically the button is just another EQ/Filter etc, but just probably somewhere different in the circuit. But, ya I feel like your tied down to the Coloration of whatever the Curve Response 1/2 are, and whatever the Flat/Non Flat is, and Flat still doesn't quite sound Flat, but maybe it is hah. Lastly, and maybe someone could help me figure this out, but normally with a Load Box/Attenuator etc, you would go from the Amps Speaker Output to the input of the Load Box, and then from the Speaker out of the Load Box, but the Juice Extractor just has the Line outputs, so is it not even meant to go straight to a Cab, and is that why in the manual the only setup examples show a stand alone power amp after the Rack FX etc? Because I thought Alan would normally use Heads, so is the Power Amp in the examples literally just to be able to go to the Cabs after the FX since the Juice doesnt have it's own speaker outputs? I dunno, it just seems odd to me that it doesn't have one, but i guess a big reason for the Juice was not only as a load/attenuator, but for all the Line Outputs to go to Rack FX, so I guess using it in that way requires the Stand Alone Power Amp after the FX so he could go to his cabs huh? To go direct to tape/DAW without a Cab works fine obv, but I just find it odd it doesnt have a Speaker Out, and also wonder how hard it would be to add one?

@@jamescassidy4045 Are you referring to the Rocktron Juice Extractor? Sorry... I don't think I can help with your questions but if you want to send me some pics of it that would be awesome. I'm most interested about the inside of it. There's a schematic for it on Reverb last time I looked... they want $60 for it. I'm curious about the circuit but not $60 curious. I've tried finding a schematic online but there's nothing out there. You can use the email address at the home page of my website - www.DIYguitarist.net

Corrected impedance curve will be in upcoming video (Part III). It's not trying to emulate a speaker cab... it's an attempt to mirror the DC resistance and inductance of the secondary of the output xfmr, with the line level taken off the midpoint between the place where the two devices connect (amp and Harness). That's how he got from something like 40V RMS to a line level signal. It imposes a very big load on the output transformer, which causes it to saturate and the power tubes to work harder.

@@VegasCyclingFreak Thanks for getting back. My only other thought was that not only did it emulate a cab load, but also provided the line out signal filtering so an cab IR loader (didn't exist back then) wouldn't be needed.

Yes but the use of the nichrome wire is what makes it different. Still investigating but I think there's a lot more to it than "it's just a different kind of resistor".

😆

I saw it on eBay in 2007… never heard of the Harness before then. Palmer PDI-03 uses a single 250mH inductor, which is enormous compared to the 10mH inductance of Allan’s unit. Also nothing out there uses nichrome wires. Allan’s units are unique in this regard.

It replaces speaker in amp so you can silently take advantage of power tube distortion, etc. It’s technically a power amp to line level interface.

Agreed

You are correct. I’ve only seen two up for sale in 15 years. Four years ago one sold for nearly $1900. Owners don’t seem to really want to help... I tried but no luck so far.

Ha ha, I design thigs that push heated/cooled air thru ducts for a living. 😁This stuff is just a hobby for me. Anyway, I learned after making this video that the Harness & Harness II units have a galvanized steel baseplate in them - in all of his units the baseplates are electrically isolated from the steel rack enclosure with the use of rubber grommets, plastic jacks, etc. Almost all of Allan's personal units (7 different versions that I know of) were built into various aluminum enclosures. Don't know if that ever caused him a problem or not. I have pictures of one custom that appears to have an aluminum baseplate in it. If I were to put this in a steel enclosure I would isolate it exactly the same way. I did have a passing thought about galvanic corrosion, but don't think it's an issue with the isolation. What would be the electrolyte anyway? I live in a desert where the avg humidity is 7-10%... but I suppose someone living on the beach in Hawaii could be a situation where it could occur.

Everything I know about it is at my website. Specific webpage is here - www.diyguitarist.net/Misc/HoldsworthHarness.htm

Yes, but it replaces the speaker.

@@VegasCyclingFreak Thats exactly what a reactive load box does.

I don't think Allan was an EE but he certainly knew how to tweak stuff. Apparently he worked on his own amps, which may have just been a necessity. Not sure what spawned the idea of the Harness other than maybe it was another thing that arose out of necessity. Maybe because he had young children at the time and didn't want to disturb them sleeping, or the neighbors when making recordings in his home studio. Probably something along those lines. He liked it enough to use it at his gigs in the early to mid 90s. It's on that REH video, too. I think that was a good sound for Allan.

@@VegasCyclingFreak To come up with something like that isn't anything like tweaking something that already exists, because it needs to be either designed from the ground up or be taken from a similar device and expanded on, and there's lot's of math (algebra) involved. This goes beyond Ohms laws, there's a lot of (mainly) Faraday in there too; induction and capacitance and the magnetic side of electromagnetism and electrical field theory, and with things like the inverse square law and what not the reason so many can't wrap their heads around it is because much of it is counterintuitive. BTW you approached it backward by using ohms laws to establish inductance rather than Faraday's laws. I know they can be established from each other, but you could have figured out the Ni-chrome coils with only math first and found you can get the very same values with different gauges and coil sizes and windings of wire, and depending on the component of the wire, then made the coils, and then designed how and where to mount them. It's how you also can account for heat loss and then some, because of material properties and energy conversion. On that note in winding coils with wire that has some spring action you even have to consider the dowel size and at which rate the wire will spring back, and the dowels which must be heat resistant to wherever you need it, and are not necessary to hold them to shape (they would have to be mounted to the dowel firmly with lacquer or similar, but to deal with the fact that when up to temp they will sag and could short out to ground (base plate), which still needs a layer of insulation between them for safety. I also noticed that you expected to be able to measure the coils outside of the circuit, and get the same value once in the circuit: That's not going to happen, as you were measuring a larger part of the circuit with their reactions to each other, again where doing the math ahead of building comes in really handy. It's why in troubleshooting you can't just measure them on the board directly, but have to de-solder at least one end to measure them, which is more work, but necessary, unless you want to go through a crap load of math to find where to what all can be measured, where to measure... to know which component will change which measurement where in the circuit to say: It must be this component, and well try that on a circuit-board crammed with stuff! The more stuff the harder it gets, and unless you have a lot of understanding can come with surprises, and add a whole other can of worms to deal with. As for the resistor to the line level potentiometer why not just find an expectable range and use a trim pot so you can dial it in, and deal with any tolerances of the built circuit that way? Since we are dealing with field theory, the proximity of the coils to each other may be a factor, and it's a way to not have to do the additional math to narrow the expected output down to a negligible value, and just say close enough and trim it at that end. It's been decades since I worked in wave theory related tech: Electromagnetism in a huge spectrum so light, micro and X-rays... for physics, biochemical, chemical, material study... related fields of research, and custom one off devices for light wave analysis, spectroscopy and what not, and I'm old and rusty now, but this is in my wheelhouse, because I'm a luthier and still design circuits going beyond how every MFG does circuitry and uses all the same value components as the next guy as has been since the 50's. I'm not bound to 250 $500k pots only... I can design them to the pickups being used, the desired results (so not whatever you get) and the customers preference. I wouldn't mind making one of those and take it a few steps farther, like switchable between 4, 8 and 16 Ohm speakers and the ability to adjust more values (EQ...) and suit more players, because as you described Allan built them slightly different for each one he made for others, which shouldn't be necessary. Oh but who would I be kidding but myself? I already can't find the time to do much of anything outside of what I have on my pallet, but I will raid your site, and download the related info, and whatever else I can find and keep it on file. Thanks for the info, and good luck.

@@Bob-of-Zoid It seems to me that Allan came up with this thru experimentation based on some previous practical experience, perhaps with hi fi systems. I've never seen anything that suggests Allan had any formal education in electronics. May be possible. Maybe he went to local library and learned what he needed? I didn't mention it in the video, but I did some tests on inductors before I decided to attempt a clone. I hand wound a few and made measurements to see how much the steel parts would affect the inductance. From the results of this I was expecting about a 50% increase and this came in lower at 42%. I also determined that there will be crosstalk between the coils that are close to each other. What I didn't understand is how one of the nichrome wires changed resistance when I put the other section of nichrome wire in there. I don't know how critical the nichrome is, it's mainly there to handle the current. Everyone else that makes these sorts of devices use big wattage ceramic resistors. In Allan's units none of the wire coils are sagging... I have no idea about the specs on those. I am aware of the possibility of that sagging, although the temps we are talking about are quite low compared to what they are able to withstand. This thing isn't a finished project yet. I will likely put some kind of insulator between them and the baseplate. Trimpot at level control is a good idea. Will keep that in mind if it's needed. Also apparently you're supposed to use this Harness thing with an isolation transformer on the output. There''s a lot of factors in all of this. I'm just trying to get this thing in the ballpark. Without having an actual unit to analyze there are still too many unverified things to say that I nailed it.

Tom Scholz is someone who is capable in development of musical electronics.

@@VegasCyclingFreak It's already so hard for me to believe he found the time for it with how much he was in demand, and how many bands, tours, and projects he was involved in! He may have always been somewhat of a nerd, I know I took everything apart I got my hands on to see what made it tick, and managed to put most of it back together right, when I was still in grade school, and learned a lot along the way, and when I started my apprentice as an electrician I was highly disappointed because to me it seemed like I was in electrician kindergarten!😂 Not all steel is alike, and only the ferrous metal content, so Iron and Nickle count, and as for being structurally sound, you can get away with none at all, and why you see them in so many devices with nylon screws and those resin reinforced fabric washers and similar. As for the change in the Ni-Chrome coils: If you started with an understanding of what they should measure at outside and in the circuit than you can eliminate something off in the circuit, and take it from there, but starting with an understanding of what to expect is best of course. They can't sag on the dowels, and sagging isn't the only reason, but knocking the thing around. That's why I suggested to wind them in a way so the wires stay put and separated and then a good drenching with any epoxy model paint should do the job, and make it road worthy, but that can wait until you are past all the experimental stuff and building a daily driver, just be careful to not bump into the coils and end up with windings touching each other. Maybe someone where you got some of the info from, like someone who owns one can give you the specs or do some electrical measurements so you have more to work with, or go with resistors, which BTW are often the very same thing with the ceramic to not only hold it together but as heat-sinks. You need to make friends with a seasoned electrical engineer and invite them over! 😅 Looking foreward to part 2, and Happy new year!🥳

You can find the schematic for it at my webpage here - www.diyguitarist.net/Misc/HoldsworthHarness.htm Keep in mind that the actual values of inductors, nichrome wire coils, the pot and resistor feeding the pot are all unverified. I think I'm pretty close but have no way to verify anything unless someone that owns one wants to help me fill in the blanks.

Thanks. Please revise the schematic if you find different values later. This could be a fun build, just don't want to roast an output transformer

@@christopherlewis1847 Yes sir, that is that plan. I don't think it would fry an OT but I have to give the disclaimer. My main problem at the moment in taking this farther is that I don't have a "common" amp with an 8 ohm OT. If I used my Seymour Duncan Convertible for testing, that OT is literally irreplaceable, so not going to risk it. I recently got in touch with someone that has four of them (he knew Allan). I'm going to see if maybe he can help answer some questions. Maybe in time I'll get my answers...

@@VegasCyclingFreak I hear ya. I build my own, but the expense of buying a new OT and installation are a pain.

Interesting way to look at it.

Not quite. A transformer induces current from one coil to another coil in another circuit. These coils are all in series and simply provide a reactive load just like a speaker does. The line-out is then in parallel with the load. It's hardly different than a "Line Output" jack on many amps, except unlike the speaker in those amps, the coils in the harness don't move a cone to convert electrical energy into sound waves, and thus are silent. Also, very similar concept as the Weber Mass and Mini Mass except those use an actual speaker coil without a cone.

@@randaji The Weber approach is interesting… uses big wire wound 50 watt rheostat(s) & ceramic resistors with a speaker voice coil.

I've been told terrible if you just go straight into some effects unit. Needs to have a parametric EQ after it. In Part 2 I will go over that stuff.

Pretty much that 😂😂

It's a power amp to line level interface. It replaces the speaker so you can silently take advantage of power tube distortion, etc. Yes, I know there is stuff out there that does this but remember Allan came up with this some time around 1990 when stuff like this didn't exist.

@@VegasCyclingFreak Ah that's interesting to know. Crazy to think he's innovated in so many more areas than playing technique. Anyway, subbed! I'm curious for part 2.

@@AOzonemusic Yeah, that's one thing I'm trying to convey, he was more than just an awesome guitar player. There's also the Fizz Buster that he invented - a thing to make beer better.

I'm not familiar with that one. He had a part in its design?

yes had a major part in designing it has a lot of unusual aspects to it when I see people speaking about it on modding forums they are usually taking this stuff out LOL@@VegasCyclingFreak

@@joanstone6740 Huh, I was not aware of that. Haven't really seen anything about that in my usual Holdsworth circles. Guess I need to round up a schematic to see what makes it different.

"The Belair was mostly marketed with a faux tweed tolex exterior and has a superb clean channel. Really one of the best, including those of Fenders. The SOAK channel ("gain") was designed in cahoots with Alan Holdsworth (I actually ran into him every month when we paid rent for our spaces in The Brewery in downtown LA), and it's decidedly "legato." Too smooth for me. There were two versions of the Belair -- the earlier version has bigger, better transformers and a spring reverb, the later version has smaller trannies (take THAT, DeSantis!) and a digital reverb. Some variants came with Rocket 50's (ack!) but for a time they were sold with V30's as OEM. Honestly, the digital reverb on the newer ones may be better than the spring box, but mine is an older version with the V30's. "' This was from a forum. Very difficult to find information I remember reading some stuff about how he designed some of the guts with filters and clipping diodes@@VegasCyclingFreak

@@joanstone6740 Interesting. Clipping diodes don't seem like something Allan would have embraced but maybe they were more like limiters. Filters for sure sounds like an area that Allan dabbled with. I found a schematic. Interesting circuit topology.

I suppose one could say that. How many of this type of thing were on the market in 1990? I never paid any attention to any of that back in the day.

It’s not a guitar pedal… but he might find my video about the Soviet Kazan wah and vibrato pedals interesting.