When people replace an old cap and say the new cap is not so good, it is probably that the old device had drifted and leaked over time, and had accidentally produced a desirable tone. Then the replacement cap will of course sound different, as its value will be in spec.
Exactly. But if you keep track of what you're pulling out and know what you are doing, you can tweak certain things. For example bumping the capacitance of filter caps for improved bass response.
@maat8249 Yeah but electrolytic caps rarely will increase with capacitance over their lifespan. Changes in value thru aging is going to have greatest effect where the signal is present such as the case with tone circuits and bypass caps where it bleeds off a certain portion of the signal at a certain frequency, or in coupling caps that will also cut a portion of the signal . Another thing to consider is how age and degradation affects the dynamic attributes of a component. How it reacts when subject to power and heat. Heat coefficients play a big role in what is considered in the sweetness of certain carbon comp resistors. These dynamics play a crucial role in what is perceived as the MOJO in certain types of aged components within the signal path. But it doesn't mean that I would want to place an otherwise inferior component device throughout the whole design of my audio circuit. But I might be able to utilize such shortcomings of certain components in specific circuit locations within the signal paths to create a dynamic response from what otherwise would be an unstable and substandard device, to the benefit of our perception of what makes a cool electric guitar tone. Pretty much everything we have comebto perceive as pleasant and standard electric guitar tone is because of what we initially have grown accustomed to in the early days of electrifying the guitar and making popular music from the crude basic amp designs of the post war time period. What is generally agreed upon best engineering and design practices for ultimate audio amplifier performance, goes out the door for guitar amplification. Best engineering practice and design is 180 degrees difference. The deficiency and coloration of the amplified signal is desired for the guitar. The amplifier is every bit a part of the tone and instrument as much as the guitar is the instrument.
Worked at Sprague electric in Vermont as a designer and r and d the black Beauty went through many iterations , ie dielectrics , insulators , encapsulation material while they look the same their properties are quite different, and the construction ie winding of the foils the mandrill size and tension foils overlays dielectric thicknesses , all made up the voltage and capacitance and frequency ratings the encapsulation material effects . Most were made to customer orders and specifications while theres some generic there specifications were very broad.
No need to put em to a vintage amp. That alone introduces so many variables that the test is worthless. A better test is to use simple test circuit and measure responses to various signals and make spectrum analysis out of that. If you don't believe test data out of such test how can you trust anything that's science based. No, you don't need to hear the cap, you wanna measure and compare things in a consistent and repeatable ways.
Q: Is there an amp that you feel is particulary underrated or underappreciated? Could be old and unknown, or a generally-disliked amp that you think really has something cool going on.
I love your vids... very informative. Hiw do you compare the new digital amps to analog? I've heard some amazing digital amps but never side by side with analog, so curious for your opinion.
I always look forward to your videos Colleen, and I especially appreciate you educating us on the technology and its history. But as my mind is absorbing all of that goodness, my eyes are exploring your workspace for something interesting. You never fail to deliver. So, all amplification aside, tell us about that cool slot car track I see in the background. TYCO?
Get high voltage polypropylene, like Solen caps. They are quite a bit larger than electrolytics but if you have the room, they are superior to electrolytics in every respect, and SO fast!
I went down the capacitor rabbit hole a few years back when I was upgrading my Stratocaster. I searched for the best tone cap with the best mojo. I tried tropical fish, Russian PiO, mustard, bumble bee, and the last one came from a 20 for a dollar pack of eBay Chicklet caps. The Chicklet was the one I left in the guitar. I couldn't tell a bit of difference between any of them as long as the values were the same. Some will swear they can tell the difference and I'm glad they can. I just know that I couldn't.
Dont't worry. A spectrum analyzer would have difficulty finding real differences with caps of equal value, construction and intended circuit purpose. But I forgot, this is a crowd that will pay hundreds of dollars for an 'oxygen free copper' audio cable. I have a National NC-300 on the bench now undergoing a full rehab. Lots of musturds mixed with split bumblebees. As was said before, better components available now. And smaller too...
@@AE1PT Indeed. I'd like to see someone actually analyzing some simple circuits with different caps and showing us the frequency and phase responses measured on various input signals (guitar, noises, impulse, frequency sweep) and on different voltages. Then of course, the old caps leak current so maybe there should be some resistor put in parallel with that to simulate bad components. :D Maybe also a torture test to see which ones last the longest. Well, maybe temperature is another variable that should be added to equation.
A strat is also a terrible testing platform because you need to take the strings off every time you need to get to the insides. This inserts so many variables into the equation that you might as well not bother at all. Any guitar where the elctronics can be accessed through a panel would be far more reliable.
I enjoy these little sessions, they help me to review the basics I've not had a motivation to retain. After 50 years of playing I'd say whatever is original spec for the amp is the best choice. When replacement is necessary, go for the best reproductions or NOS. (but as an option, certainly Sprague would be hard to argue against!!)
I find your voice calming. I could listen to you read the phone book and be fine. The fact you teach about amps and electronics is just an amazing bonus!
Of course the old caps sound better because they are filled with "old sound". When they leak out all that old sound goodness, they loose that old cap sound. That is why you need to replace them. Always replace them with old caps because the new caps are filled with "new sound". New caps with that new sound filling make the music sound sterile and cold.😁
You get bumbleebee caps in old McIntosch Amps - i changed them out as if they go they will take the amp with them and this amp was 65 or 66 - i used a good cap that was recommended in the Hifi forums--- i had a cap tester and they where ALL out of value...............specs where pretty slack back then - the BASS was a lot tighter after the work and i wasn't worried about my $5-6 k amp
If it’s a coupling cap and leaking DC to the grids of the output tubes, then it will make a difference in sound because the tubes’ bias may have changed.
Q: Would you ever make your own Amp?Like you could start in the sweet spot with a 2×12 combo of your own Amp design, and choose your speakers for it etc. That would be cool 😎
Hi there, awesome information as usual and thank you for the knowledge you share,…question- what is your go to electrical cleaner & how do you clean the electrical parts? I bought a ‘68 SR Drip edge, and it crackles all around the top when you tap on it. I thought of just give a good cleaning and take pictures/video before I take it to a tech here in Phoenix, maybe that’s all it needs.
That was great. The way these things fail is interesting. I guess carbon comp resistors become capacitors when they fail. This isn't really a question, but you talked about microphonic effects when you were showing us that Premier 71 amp with the reverb. That is a really great sound it makes. Aren't valve microphonics a part of that reverb sound? Producers like Syliva Massy use amps and re-recording as part of the production process and when I heard that amp I could understand why. So how can you tell when the sound of an old amp is right? I guess you just need a good ear and a knowledge of how they are made and how they used, and you clearly have a lot of that. Thanks for making such great videos, and I hope you have a great New Year!!
Yes, it is possible to bias by sound alone... as long as you're staying within the 10-40mA per tube bias range. Ken Fischer talks about this in The Trainwreck Pages.
Hi from the UK, great videos. Q. If you had a modeling amp (Kemper, Quad Cortex) that played and sounded exactly the same as a vintage tube amp would you continue to play the tube amp as it's the real thing or would you play the modeller as it's all about the sound not what makes it?
Regarding the "black beauty vs modern" question, there's quite a few parameters for capacitors beyond just their capacitance and whether they're polarized. The voltage rating is the next obvious parameter but doesn't directly impact the electrical performance within the operating window. Then there's ESR and ESL which have the biggest impact on AC performance, and DC leakage which in a non-fried capacitor should be functionally zero. Then you get parameters like bias voltage and temperature dependent changes in capacitance, dielectric absorption, and piezo/microphonic properties present in some types of capacitors, which mostly limit what types of capacitors are appropriate for what applications. There's a whole rabbit hole you can fall down with this subject With that out of the way, I don't think anyone will be able to pass an ABX test comparing a modern mylar capacitor with a vintage black beauty. The truth is that audio applications are really, really not very demanding on capacitor parameters. So long as you've got the right type, value and voltage rating and aren't using absolute garbage quality parts, you're gonna get great sound.
I have been borrowing an old magnatone lap steal it has an amaizing tone knob that gives a wa wa sound while also droping volume, so that it is funcionaly a tone and volumeat the same time. I have not opened it but I expect to see an old paper and oil cap. Its "bad " but sounds amazing. is it possible to reproduce this volume /tone with modern components?
Hi Colleen , ? What tone control circuit do you like the best and have you experimented with any of the tone control circuits that are out there like changing a fender to a Gibson or vice versa or high watt or Marshall I know they all have slightly different setups just wondering which one you like the best ? Thanks and happy holidays
I took a capacitor apart. It appeared to be aluminum foil with like paper in between. Small with two wires and that was it. They say ceramic caps very depending on temperature. I love your videos. You define what cool interesting knowledge is. You Rock.
I have been restoring antique radios for 40 years. I have bags and bags of bumblebee caps removed from antique radios. Probably thousands of them. Am I sitting on a gold mine?
The only Bumblebee cap replicas I've tried are the Emerson ones. I have them in both my Burny LP and Ibanez PF200 (btw, the Ibanez Performer guitars are so damn good), but I have no idea if they are close to originals. I honestly couldn't say if they make much difference to the tone at all, but I can say that it's much more fun to mod guitars with high quality components than just buying some okay cheap components to put in them 😄
I had a bunch of NOS bumble bees a while ago. I put them in guitars (not amps) and there was no difference. I am not immune to mojo though. I used to argue that different germanium transistors made a difference in circuits, beyond the measured values. I collected 100's, buying old radios etc. I made a Range Master with two transistor sockets and a bias knob. I proved myself wrong!
I've been playing music in some fashion since about 1980. Until a few years ago, the entire notion of 'having an ear' to me was about being able to listen to something and play it. All of my musician friends could do that. I could not. Now I am seeing, more and more, how there are many kinds of 'great ears'. Pedal builders. Leo Fender. Jim Marshall. I rarely ever discount when anyone says they hear something I don't.
you have a broad knowlege on Amplifier Circuitry and love all your repairs ,Im still in deep research mode and 1 thing Im a little stuck on is what type of capacitor to use in the circuit and what not to use , I do have a Electronic background but basically it was needed to get my Electrical Certificate years ago so didnt ever apply that knowlege because Electricians just replace the whole board ,but I would love to see you do a Video of what capacitors you use to replace the old out of spec caps ,Merry Christmas hun !!!!1
About the sonic qualities of capacitors, it's interesting to look into how subjective impressions of sound fare under controlled conditions. The amazing Stradivarius violins are not preferred by violinists when they don't know who made them, to cite one striking example. As electrolytics age, the dielectric absorption increases greatly which has a deleterious effect on the sound quality in an audio amplifier but a guitar amp being an instrument rather than a reproducer, the net effect may be considered positive, depending on what the musician may be after. Don't even get me started on what we like to call magic cables. Any educating you might want to do would be a service for your viewers so they can spend their money wisely on things that really work.
I can't comment on sound quality but I too try to keep the old capacitors when they are still good. I fix a lot of WWII (and newer!) military radio gear for friends and it amazes me how so much of that old gear is either fully functional or has only one bad component. A recent ART-13 transmitter I fixed had never been used, from 1942, and the only problem was a leaky screen bypass cap in the audio amp causing low modulation. That's it!
I have two words for y'all that get hard ons because of BB/bumblebee caps... Vitamin Q!!! The reason that BB caps get leaky is that the case seal becomes compromised and moisture gets in the cap and reacts with the acidity of the paper(All paper has acididity in it, from manufacturing). Vitamin Q caps are hermetically sealed so they rarely if ever, leak... In fact Vitamin Q caps are about the only paper cap that I won't replace as they are almost always good. You're welcome! Lol!
Are there any brand-new amps that you deem equivalent to your favorite special vintage amplifiers? Which are destined to be the coveted amps in the future? Are there any viable vintage-like amp DIY kits you would recommend?
Hi Colleen, I’m a college student looking to work in guitar and amp repair in the future. I was wondering if you have any tips for growing a customer base? Thanks!
If they are not leaky now, they will be in six months or year. Mylar ones are better but would also leak dc in time. Problem is with black coating that develops micro cracks and moisture gets in. Cracks can be revealed if you put them in boilling water, there would be small bubles along the crack. For replacement i recomend Solen (French), which are close in sound and much more durable. Another alternative are Illinois Capacitors which are excellent, but little brighter in sound. For electrolytics Panasonic NHG gives great results. i think that i recognize RCA Senior Volotohmist and Simpson multimeter on shelf behind you, i have same ones. Would also recomend Sprague Tel-ohmike cap analyzer or at least Heath IT-11 for next show. All the best, keep up the good work.
Young lady, I would like to know what your background is. You gave such an authoritative, informative, and professional presentation my thick head seemed to glow a little brighter. What really impressed my was that you were able to explain "older technology" so well that you could be a curator in an electronics museum. I am impressed!
That was fun! I love the history of electronics. There is a mystique with bumblebee capacitors. They can be very expensive! Capacitors can definitely affect audio frequency performance. If you want to become a good tech, you need to know the details about resistors, capacitors, inductors, etc. I am certain Colleen knows this! She is an excellent amp tech. My question is, "What are your three favorite guitar amp text books?" Thank you.
I've heard that "domino" style caps also share legendary status. Which parts of an amp's circuit don't require a particular cap type in order to sound it's best? And, which type sounds best in certain parts of a circuit?
About 20yrs. ago,I talked to a woman at 'wal-mart'-checkout,who worked for 'Sprague'.She told me how they tested the capacitors'.A really fascinating conversation!
How did you get into amp repair? Also, do you have a place to buy your merch? Thank you Soo much for your vids, I have learned more than I care to admit not knowing haha happy holidays
Great tube caddy and that Ohmite little devil resistor rack. 60 year old Mylar cap hold more cache that they really should . Since your using them in a Musical instrument the flavor does matter more than pure spec in other applications. Your closer to cooking than pure science here. That not a bad thing the proper application for it use. Nice video .
Do you have any cool learning resources on how to fault find and fix electrical gear? For example amps or synths. Or is everything you do from experience/feel? Great and interesting videos, even from a novices pov. Keep it up! Have a great new year!
I bought a re-issue Les Paul that supposedly had bumble bee capacitors in it. After opening one up it was a yellow SoZo capacitor. It really didn’t surprise me lol. Why did I open it up? At the time I bought it around 2015 there was a buzz about them not being real.
I love looking at the old sprague components. They're like antiques and you can almost feel the pride and the feeling of like doing something important that is so new, like they used to make them by hand, and it's a whole different world, when you see how everything just was shrunken down and made by machines later on, by they still end up arriving at just a handful of packaging options and I'm the heyday if radio, they were still figuring it all out. Also the type of materials can be so much more exotic and they probably cost a lot of money relative to today. I used to hang out in the surplus when i was a kid for hours looking at all the surolus from the national laboratories. Such a treasure chest. Literally millions of dollars of components because it's from a lab that was then considered junk at that point. I w ish that store was still open.
6:01 DUDE!!! No!!! Just cuz they’re leaking DC voltage don’t mean ya can’t use them in guitar tone circuits!!! Les Pauls LOVE bumblebees! I’ll take any ‘bad’ black beauties you have! Seriously!!!
Shush! Don't let out the "secret"! Field coil speakers are great but a regulated DC supply is needed for the field coil... Otherwise there is a lot of hum at the speaker. You gotta know what voltage/current the field coil wants or it will be easily blown.
Very cool. Who doesn't love a Bumblebee 😀 I have a couple of questions for your final video. How do you check a cap for DC leakage? And how you you check components that are in circuit? Cheers Richard.
I can sell you some (original,vintage ..) quantum,electro weasel capacitors , that sound amazing, But they are very expensive ... because ..the more they cost (you) the better they will sound....(to you)
Once I had four Fender 6G7-A Bandmaster heads -- One had been thru a flood and I totally rebuilt it with modern components (new iron, Mojo Dijon and M150 caps, Xicon carbon film resistors, etc) --- I'd set up all four heads in my shop, let people play them and then tell me which one was the rebuilt one --- Not once did anyone pick out the rebuilt amp correctly -- they couldn't tell it apart from the other three original (but serviced) amps --- That's when I stopped believing in "Magic Mojo Parts of the Past" --- I think many modern parts are as good, or better, than old $$$ Vintage parts --- But it's hard to convince some people who "Believe" that vintage parts have some kind of Magic Properties --- sell those old caps to the Believers for big money !!!!
Thrue, if rebuilded correctly, it would work as original. Problem is that rebuilder sees 8uF in AC30 rectifier network and installs 22uF and thinks that it would work better. Old irons where small and band limiting, people install HiFi output trannies and then wonder from where all this bass came from, and why it is not so loud any more.
@@sinisatrlin840 -- It helps if one is able to read a schematic and can build the vintage circuit correctly -- I used to buy old tube PA heads and rebuild them into guitar amps --- I'd gut the old components (throw them away) and build a new circuit (usually a true PTP build of different Tweed Fenders) with new components --- People would marvel at the "Authentic Vintage Tone" these amps produced :) --- And they had the reliability of a carefully built new amp (w/grounded power cables and fused AC Supply and HT)
@@markbernier8947 "It helps if one is able to read a schematic and can build the vintage circuit correctly", it usually helps, but vintage components had loose tolerances, el caps where +50/-20%, output trannie on SE Champ was in size like gnat (for a reason), tubes where much superior than current production. Biasing was done incorrectly, shematics had errors in them. Lots of variables, and then New Sensor (Sovtek) sells you rebased CRT sweep tube as nos 6L6GC and than we all think that Soviet tubes are not good.
black beauty caps are just as good or maybe worse than good caps for HI-Fi. Capacitors massively effect the sound of an amplifier circuit but making capacitors is not some lost arcane wisdom. The Mod and Sozo caps sound great. I'm not sure if there is a manufacturer out there making caps with the same specs as sprague black beauty's but it should be possible.
A friend of mine in Japan took some samples of Black Beauties to a premier Japanese capacitor manufacturer and said he would pay NRE for them to develop an equivalent. They said they could use the same materials, but they couldn’t figure out how Sprague managed to wind them so tightly (which is something Sprague was quite proud of). They gave up because they didn’t think they could do it.
Good comments, Colleen. Black Beauty caps usually leak, causing grid bias distortion. Some musicians like distorted sound, but it is certainly not good for the tubes and transformers. NOS bumble bees leak also, as they have been around for 40-50 years as well. If people like their looks maybe they could restuff them to keep original look. Happy 2024...........
Q: Any thoughts on taking video production on full time? It’s nice to see younger generation doing this stuff. Sorry Uncle Doug! We can’t wait for more content thank you for all you’ve done.
Do you service more modern PCB based tube amps like say mesa boogie ect?.. Favourite guitar amp/amps of all time? Great Channel! I especially enjoy your interviews with old school technicians.Happy new year! Looking forward to more videos in 2024
Happy New Year's, Colleen! Cool videos. Not a technical question, but you live in Los Feliz, right? I haven't been to L.A in 26 years. Do they still have all those cool pawn shops in Hollywood?
Q: do you think modern amps will survive as long as vintage amps? A ‘65 Twin is by now almost 60 years old and still perfectly servicable. Will a Marshall JVM or a Mesa Mark III survive untill 2080?
Hey, Faz. Eric Tripton here. This is pretty basic but here goes. If I am just replacing output tubes in my Germino Plexi, do I really need to bias? Does it make that much of a difference if I pop them in and off I go? Thank you.
You can pop in new output tubes in a cathode biased amp with no problems... The amp you're talking about has fixed bias and that means the amo will have to be rebiased with every new set of output tubes you put in that amp... Unless you can get another set that has the exact same parameters as your old set... Yeah I know, I'm not as hot as Faz but your question has been answered... Lol!
Hi! I know you probably work mainly with tube amps , though I have a solid state amp question if I may. I have a peavey bandit 112 red stripe that’s USA made. And I’ve been giving thought to a speaker swap and /or a separate additional cabinet. The amp is 80 watts as is. When a cabinet is connected it bumps up to 100 watts. My question is regarding the speaker type I should look for to replace the amps built in speaker with. I would like a musical sounding , wide spectrum type that handles lows and highs well but sits in the midrange mostly. Do you have a suggestion ? And if so , would that speaker be a direct swap ?? Thanks so much.
Q: Speaking of caps, I just bought a 53 5b3 for a great deal :) It's had some repair work done previously by Todd Sharp over here in Nashville. The transformers are original but a lot of the caps have been replaced. Interestedly enough someone replaced most of the caps with blue molded ones from the sixties, the same ones I see in my 67 silver face deluxe. I'm curious your thought on how the blue molded caps compare/sound to the Astrons in the 50's amps. It seems pretty cool someone used old caps in there to me even if they're not exactly what should be in there... Btw Always enjoy your videos and happy new year!!
Q: I know you work on tube amps, but this fits with the capacitor theme. I have a Fender Performer 1000 that I opened up to see if it had any burns on the circuit board (apparently a typical issue with that amp). Didn't find any burns, but in the meantime, I broke a capacitor connection. Any point in repairing this amp (or more likely given my soldering skills, paying someone else to do it)? Thanks.
6:05...that looks like a paper dielectric...I'm pretty sure that the mylar dielectric capacitors are all right. Is there a way to identify the bumble bee capacitors that have the mylar dielectrics?
