Documenting a very nice and properly working Heathkit WA-1 vacuum tube power amplifier from the 1950's. It does an outstanding job from 30 to 15 KHZ at 20 watts.
Hello El Paso tube enrhuiast! I luckily found you're RU-vid channel last night and have been up all night watching and learning! I've been collecting tube gear transformers etc etc since 1988 when I was only 18 and oddly enough people and physics departments companies radio stations were just throwing the stuff away everywhere as cd and solid state was so in favor. I heard a heathkit Williamson w5 highly modified with balanced resisters vitamin q caps everything balanced so the push pull and phase inversion went back into balance. Through a nice turntable and altec Lansing voice of theaters and I was so in love I sold all my expensive gear and bought all the tube gear and analogue hifi equip I could find! I even have some rare utc for audio only edition power transfirmers and chokes meant to be sold as pairs for dual mini power supplies 800 cr tap 20a etc etc and tons of peerless and accrosound opt matching even nod in box same day made sold as matching pair never even soldered. Nothing like your collection but I have amps need fixing some i e been able to of w2, w3 w4 and w5 as well as citation 5 with bypass tube power supply. Was gifted saved from a dumpster a lambda tube regulated power supply and two huge techtronix with four 6l6 power tubes in regulation stage all for preamp 0-275 vdc range with heater taps- I could go on and on...sadly few years back I broke my back in a car accident acsenibtruck hit me also suffered a tbi injury so my tinkering and fixing amps was limited but my passion was not. I saw your video on the Williamson wa-1. After decades of looking to find a pair of those I acquired two however one is a dead ringer match for yours the big red caps everything works great. The other has yellow caps and doesn't match the specs of the other. I love dual mono over stereo or mono. I'm wondering if you'd consider a sale, trade, any combo of above as completing that pair with a matched 807 to my red cap good condition one has been a last dresm of mine. I don't know if you still accept audio projects but I also have. A few including those utc transformers and variety of other ideas. I also have a vt25 anp like the one you buildt but my specs and preformance are much better than you got bout of the vt25a model. I didn't see a contact email or number or address. I'd love to send you pictures of all the gear I'm getting ready to trade sell all kinds of old eico preamps to main to integrated to hesthkit to random transformers and output transformers and boxes and boxes of nos old tubes and used test better nis on my recently cakibrated tv7 and ma Meter added by a kind fellow your area of our good country. I had a few thoughts as to why you mentioned in your videos why you liked those 2a3 like triodes. I could list 100 plus reasons why tubes made in 30's to 60's even 70's just sound better no word captures the quality aspect even when new made ones may according to test equip look 100 percent they are missing everything from the decades of craftsmen ship and skill those old timers had and apprenticeships the unlimited funds put into them espially during and after ww2 Cold War and beyond done best tubes I've bought are from the NATO supplies a soldier sold me after t hey finally switched from most of the tubes just in like 2006 completely as some radar units even in air traffic domestic 12ax7s accuracy and longevity were so hard to beat little airports across the country have had (I've seen them) sheds full of cases of nis tekefubjens mullards etc until fairly recently! My military buddy said we even made certsin tubes up till 1988- I have 1987 stamped nis boxes. That's amazing as still making is way different than not using it implies intention to use many more decades if still continuous production decades past I had any knowledge of also in case of emd pulse of course tubes still work while diodes chips silicon will melt. Anyway, getting older my health isn't the best, dealing with my back and biopsy for tumors hopefully treatable as I've lived gealthy. I'm getting rid of 90 percent. If my equipment and tubes to give others a chance at the pleasure as a lot of what I own you can't find it but for any price.thee days. Oh I forgot, I'd bet if you compared a quad or pair of kt66 grey glass nos or used test matches both gm and ma of plates that even though new production may match values you'll find that those 6l6 amp steep you converted sounds as good or better than those 2a3 equivalents you out in them! I've just heard it so many times the older the tube if good audio tube in general the older date if tests good better it generally sounds. I paid up to 800$ a matched quad for kt66 in box back before eBay late 90 s and 600$ to 800$ up till 2010. Price wVers abit niw but 100-200 a used test nos consistent price for 30 years speaks volumes when you can get same new quad for under 100$ when first made. The quality of sound even with simi liar numbers is night and day it would explain the unexplainable better sound your hearing ftom those 40 s tridoes. Or at least a large part of it! Before I was gravely injured by a semi truck that tboned my drivers door going 60mph- a mirical evi survied- I was a professor and invested in dozens of older tubes. The kt66 a favorite of mine sounds different from 1930's up to 1070 s but the test data will show same numbers however the metalurgy good construction triple and high quality mined mica support reduces mucrophonics. I could go on and on and on lots of these guys were fired in their prime at factories to save no net and the tubes quakity just pulled t h E floor out under them. Same with Russian made new tubes late ninties early turn of century alit of 60-80 year old linemen and foremen managers knew this trade from a boy were all "let go" and all kinds of nuiance trade secrets you only learn with apprenticeship and decades of hands on eirking not printed in any school textbook were. List and one year new mafe tubes in China Sbd Russia were "ok" sone factory's decent even next decades theybwere notbeven acceptable and companies that resold them had to buy thousands and test just to find a few quality quads and matched at that upping the price and wrecking people's lives and a goid industry. I have a good friend makes a living selling vintage tibes back in Rockford Michigan where I grew up- I'm in northern Cali now where I taught be flush for along time. I'd really value it if you could spare time to contact me if you don't have time for projects maybe you'd consider a trade or sale as I have lots of a huge variety of tubes for sake including lots of unknown tubes of equal quality to ones people pay thousands for just no one bothered to do all the research. As well as all kinds of kit amps ftom 40s 50s 60s with great iron on them mains and output and chokes. And all kinds of altec Lansing soesker gear even extra pair of voice of theaters. 515b's and 802d drivers. It would be a dream come true to match that 807 Williamson I have with red caps as I've seen yellow and others but not this red I've searched for for 12 years now. If it has screen taps it might be a w2 there were several versions some in between w1-w2 had ultra linear added but label still said w-1 iriginal w1 was not ultra linear had resisters to drop screen voltages and i don't even know if it had negative feedback. The w2 did and the w3 is just accrosound output transformer version of peerless using a 5881 instead of a 807 some w2 s use 807 some 5881. A Japanese audiophile I happened to make friends with sent me all kinds of translated material on esrly transformers kindly as I'd had bad experiences with mega Japanese hifi buyers in the minor ties not kind at all. He told me that the prefered tube to use above and beyond the 5881 or kt 66 nos best stock even is the 5933 with the anode cap a military version of thev807. There's a 5932 no snide but much oriced. The 5933 is affordable. He said there's three versions one is heads and tails above the rest the super black smooth metal plate with the jokes in it but not round holes slightly oval he said that version should sell for 600-800$ each if you priced it by how it sounds and advices to buy some as soon as word gets out even in Japan the market will be drained just like old kt66 s although some have surfaced past few years. I bought hundreds at 1$ each if 5933 . You can wire any Williamson to use 807 as long as screen voltage is right the plates can handle much higher voltages thsn other 6l6s! There vt100 vt100a and my favorite sounds more like a 350a or b if wired up right not well known at all is the British mikitary version labeled ats-25!!!! Best of all 807 s I've ever heard close to 350a except that sprcial 5933 black dark smooth with oval punched holes. Two other black holes ones not near as good. I've found 6-8 more other 807 cooies other designations totallybdifferent layouts of plates etc nobody knows of mine were made in 1939 by cossor for ww2 British so frequency range is huge and although not best for transmitting radio great for audio!. I'll save other secret models for if I contact you as not in my head arm all the varient numbers. Hope you have wonderful day- my email I use for RU-vid is mysterywasthebest@gmail.com ( mystery was a cool Norwegian firrst car I was friends with for 18 years knew over 100 Emglish words!) Sincerely, Mark Owens Ps- I enjoyed you r videos a lot thanks for sharing knowledge inspired me to start taping all of my gear before I sell it while recovering from my mefical challemges! Cheers!🦁
Hello David! Interesting to see an 807 power amp. They don't put out a lot of power, but sound nice. I recently repaired/restored an old Presto disc cutting amplifier that used 4 in pp. Fidelity is actually good. Still enjoy your videos :) Keep 'em coming.
Hi Frank - I hope you are doing well. Yes, the 807 is a pretty much a forgotten tube but in reality, it is still a dandy. I guess I have stepped back from the idea that I need 500 watts to play with and have been enjoying even 15 watt triode amplifiers. I have not gone the SE route yet and I don't think I will. The highly sought after UTC transformers I have to build and play with lately will keep me busy for a while. I flip back and forth between RF and AF amplifiers. Good to hear from you.
Great video. Top cap tubes with Bakelite bases like the 807 / 1625 tubes most definitely have a coolness factor that cannot be denied. Standel used these tubes in their guitar amp combos with great success before a disastrous batch of bad OTs caused the company to decline through warranty returns. Apparently, they sounded great. BTW, I saw the Standells perform with Standel amps as a teenager!
I think the shape of the 807/1625, much like a coke bottle, has in it the Golden Ratio and we find a natural beauty in it. And when we think about it, the venerable 807 has the characteristics of the modern day 6L6GC (with much higher plate voltage, and power output, thanks to the top plate cap) during the days of the metal 6L6 which has a whole lot less of everything... I have never heard of the Standel amplifier until now. I am not a musician but I have to make a confession. A few years back, just after retirement, I started a home based vacuum tube amplifier repair shop. Made a website, business cards, mouse pads, a few small things like that and took in amplifiers to help the musician community and make extra money. Met a lot of wonderful people and (finally) learned a little (with a lot more to learn) about the music world. But the confession is this - I really wasn't primarily interested in repairing amplifiers - I wanted to play with them in my workshop and document them. So, I got people to bring all kinds of amplifiers to me and that I got to examine them and see how they perform and were built and got paid for it. That is a win-win. I did have one other objective and that was to document the harmonic profile of each amplifier so that amplifiers could be built, with an objective way to measure them, to sound like any amplifier chosen - without having to duplicate the exact circuit. Well, I was very naive, since I am not a musician, and had no idea that in solid state amplifiers, this had already been attempted to make them sound like vacuum tube amplifiers. According to musicians, the SS amps don't do a good job trying to sound like a tube amp but after some time and thought, I realized all of this could probably be best modeled with computer programs instead of the tedious measurement and documentation of actual amplifiers using a spectrum analyzer. I have a beautiful HP 3580A which I absolutely but is brutally slow in tracing low frequencies. I finally stopped that crusade and just got back to sharing what I do in the workshop with AF and RF circuits. I guess that is enough digression for the night... Thank you for you kind comments.
@@ElPasoTubeAmps Wonderful story - thanks so very much for sharing. Transistors ( I call them "sand" components because they're made from silicon which is the primary constituent of beach sand) are natural current amplifiers and have to be manipulated to be voltage amplifiers. Vacuum tubes, on the other hand, are natural voltage amplifiers and, when run within their recommended parameters, are very linear (6SN7, for example). Transistors, for musicians, are best used in bass amps as they can lend an "authority" to fundamentals that works for live music and a heftiness which rockers love. But, when over-driven, they just sound horrible - nasty 3rd order harmonics and 5ths. Vacuum tubes, when over-driven, produce predominately 2nd order harmonics which, although are a distortion, give music a lushness and three-dimensional quality to it. Solid state works best for signal-processing, not amplification, IMHO. I watch several channels on RU-vid related to all things tube but yours is always a pure joy as your methods and philosophies are spot-on and your use of real world, real-time analyses are useful, practical and comprehensive. I do love your enthusiasm for big components, big voltages, big everything! BTW, I live in Albuquerque which I always considered a sister-city of El Paso as we share a common history as major stops along the famous Camino Real. Thanks again.
@@radiojet1429 Albuquerque - that is great. I have been there lots of times. I really appreciate our discussions as you give me great ideas. Been busy lately so I haven't had much time to work on the amplifier testing the little RC circuit. In a sense, it seems much like a "tone" control network. Remember the simple tone controls in the old radios where they use something like a 0.05 uf in series with a pot? Problem is, with my experiments is, I don't know what "instability" I am trying to solve... as far as I know, I don't have any. You know some amplifiers have a zobel network on the output transformer. That seems to do little for me but, once again, attenuate highs and increase THD at 20 KHz. I read an article the other night, if I can find it again I will forward it to you, where the fellow had a very slight ringing, just as I do, but compensated it to a much smoother leading edge and said he did not like the sound afterwards and went back to the circuit with the little bit of ringing. Maybe he "dulled" his highs. I will try to fine it after an errand I have to run. Stay safe up there in Albuquerque...
I want to go shopping with you man. I can say I love the single ended stereo 807 amp I just finished, they are lovely sounding tubes and real cool to look at to.
I have some real projects in my head for all the nice UTC iron. May take me a year to get most of it going but I will keep working at it. I plan on a triode stereo amp using the new Svetlana SV572-10 tube and a pair of the UTC LS-61 transformers. I recently have had a love-affair with the triodes and I have six brand new triodes as above.
i really think u should do a comparison against what u got with stock old caps vs recapped on this amp in particular that why u could really show the actually difference between keeping the old stuff vs recapping i got a feeling that little amp might surprise all of us
Hey there! I love your videos, figured after watching a few I'd write a comment. I recently found a 1955 DuKane 1u460 public address amplifier collecting dust where I work. They granted me a salvage ticket and I was able to bring it home. It has a 5u4g rectifier, twin 5881s, two 12au7s and a single 12ax7. The three microphone channels each have empty slots for a dedicated stepup transformer and 12ax7 preamp. I only use the aux 1 and aux 2 as inputs, which are mono RCA jacks. Tubes appear to be the original RCA tubes except one 12au7 is a Sylvania, unfortunately the 12ax7 RCA has a filament flash on startup so that tube likely will not last too long. Miraculously, the amp works with the old tubes (although I exchanged them for new ones for testing) and all I truly needed to replace was the power cord. There is a noticeable 60hz hum that I would like to reduce if possible. Which components would you suggest I replace or check? Rectifier filter caps, grid resistors, etc? I work as an electrician/industrial process technician but it has been about 12 years since I went to electronic school. Clearing dust on the brain and the amp it seems. Cheers and thank you for the great channel.
First off, that filament-flash is not a bad tube. Mullard, Amperex, and Telefunken and others in the European countries made some of the best tubes ever produced and that filament flash is proper. I understand it was an attempt to warm the tubes up quicker so the preamp/amplifier would work a little sooner. Check the brand on your tubes. You very well may have some real jewels and some of the information on the Internet about these filament-flash tubes is just dead wrong. As for your hum, odds are some of the electrolytic power supply capacitors have dried out and the capacitance had reduced to virtually nothing. You can (very carefully because of the HV) just jumper in with test leads, good electrolytic capacitors across the existing ones in the amplifier which some are likely to be canned capacitors. If you jumper in one and the hum goes away , you just found one that is bad. Many people leave the cans in place just to cover the holes and keep it original looking but if they are bad it is best to electrically cut them out of the circuit. Sounds like you have a great find...
@@ElPasoTubeAmps Thanks for the reply! All the tubes are RCA American tubes, except for one British RCA and an American Sylvania, which are the 12au7s. I have them removed to protect them while I figure the amp out, with good new ehx tubes for the 12ax7/12au7s/5881s and a JJ rectifier. Would rather one of those go bad in case I make a mistake than the old ones. I managed to find some good capacitors, I'll attach jumpers to it and try that method out. Thanks for the info! I'll send you a link to the videos I have of the amp.
@@ElPasoTubeAmps I'll second the motion on filament flash on the Euro 12AX7 types. They look like they are going nuclear when first turned on. I have no idea whether they last longer or shorter than US types over a longer term. I don't know why they flash on startup but they do.
I think we have finally realized that some of the vintage Heathkit amplifiers with the Acrosound, Peerless, and Chicago Standard transformers built to the Williamson design are true classics and perform exceptionally well up to 20 watts or so.
Hi. With all you knwoledge, working with tube amplifiers all these years, do you know any schematic of a class a amplifier with around 15 to 20 watts. These 807 output tubes, could eventually be used in paralell, to produce more output power in class A mode ?
Here is a link that I recommend for finding a treasure of schematics. lilienthalengineering.com/100-amplifiers-chapter-1/100-amplifiers-part-2-1945-54 There are three other files (books) of vintage amplifier schematics. You just search for, "100 Amplifiers - Part 1, 2, 3 or 4" They are by Lilienthal Engineering.
I had a pair of Heathkit A 9 and Amplifier company of America . I think A 9's were 20 watts each though i could get more out of them. I was using a preamp so I was using them as mono block power amps.
I believe the 20-40 watt range for a first-class amplifier and a set of efficient speakers is all we usually need unless we want to drive the nails out of the walls. Sometimes I want to do that... :-) but, on any reasonable level, the power amplifiers, I believe, are in the "sweet spot" of performance at this lower power level for the 6L6 class of vacuum tube amplifier. Many of the vintage audio systems deliver this performance going back to the 1940's and certainly in the 1950's and 60's. Transistor, solid state, amplifiers stormed the country in the 1970's and the rest is history, as they say.
David it is indeed a WA 1 there are two versions the triode connected version has a Peerless 16258 and yours has a 16277 ( like the. WM 2 ) with UL taps ,you are very lucky those plastic plate caps are ALWAYS melted !.I have the triode schematic/manual if you need a copy regards
Thanks, Don. I agree that this was a real jewel of a find and as you say, plate caps not melted and it performs very well. I carefully balanced the cathode currents tonight and retested and it performs exceptionally well to 15+ watts (I am very conservative) and good at 20 watts and a little more.
hi,i made a 807 single end and there is something that i dont understand why cathode resistor of the output that i see often on shematic is 10 to 15 times the value in watts of the cathode resistor . If i calculate with ohm law p=v*i the value is 10 times less.
I will do some ball-park type calculations for you. Suppose you want 37 volts bias, a reasonable value for an 807 or 6L6GC and you want as much as 100 mA cathode current under full sine wave drive. So, R=E/I which turns out to be 370 ohms for the cathode resistor. Now with 37 volts across the 370 ohm resistor, we have 3.7 watts dissipation so to be conservative and not have the resistor get really hot, I would use a 10 watt resistor although a 5 watt would be OK but could run really hot. Hope this helps.
Hi. Nice video. Viewing the original schematic , there are two p10 conectors between the pin 8 of the output tubes. Can you bee so kind and explain why or what is the purpose of the conectors.
The two plugs are used to insert a current meter so that the current thru each 807 tube is balanced, usually around 50 mA per tube. There is a pot on the top of the chassis for this adjustment. This type of balance procedure can be seen in a video I recently posted on a UTC W-10 amplifier. (PS) if you got an email reply about four tubes, it was because I was writing to you about the UTC W-20 amplifier and after hitting "save" I realized it was this video about the Heathkit amplifier and not the UTC amplifier. Hope this doesn't cause confusion... :-)
I agree that the motor run caps are fine. They work perfectly well and at those voltage levels. Overall, probably last much longer than the electrolytic's.
@@ElPasoTubeAmps thank you for agreeing I have been testing every capacitor I have and all the hvac capacitors I tested are spot not and have 0 esr and vloss and all my filter caps are 20 percent off and higher esr I have been using all oil can caps only I work in the trades and a electrician friend gave be a bunch of new ones and been having great success I even got alum and made my own chassis with a break at work and that’s a big savings I also got a bunch of vintage transformers and been making separate power supply chassis I need to find very good schematics for a push pull 807 amplifier if you could help in anyway
@@jimcatanzaro7808 Here is a link to most all Heathkit schematics. I would recommend the very one in this video as a great example of a Williamson design using 807. web.archive.org/web/20040126114241/www.circuitarchive.fsnet.co.uk/heath.htm
Just a thought, why not put a delay relay in the heater circuit of the rectifier valve? That will also bring up the HT slowly rather than a sudden jerk. By this time the other vales will be ready to run.
Good thought. We would have to check the current rating of the contacts on the delay-relay to make sure it could handle three amps for a 5U4 but I love the thoughts added to the conversation. It absolutely helps me in my future projects. Thank you.
@@meshplates That is an interesting idea - like a 6AX4 which I may have several of. I will have to look up that tube and check the max plate current. I am thinking it has a separate 6 volt filament/cathode. Thanks for the good idea.
I understand that so well nowadays. Many years ago I have had probably every one of the W series of Heathkit amplifiers and as I mentioned in the video, I not appreciate them. I wanted More power - lots more power but now I understand a really high performance 20 watts is the perfect range and many of these vintage vacuum tube amplifiers perform beautifully.
hi.i love your vidéos on you tube i learned ,id like to know if i can put 600 volts on 807 .my amp is single ended class a triode connection.thanks a lot
Thank you. I am pleased to hear my videos help - an 807 is the equivalent of a 6L6GC and with the plate connection on the top of the tube, it can handle much higher voltages than the 6L6GC with the plate connection on the base of the tube with pin 3 right next to the filament pin on pin 2 where a HV arc is more likely so you can run higher voltages on the 807, as much as 800 volts. I do not know the recommended configuration and voltage for a SE 807/6L6GC and raising the voltage will increase the plate load resistance but it should be OK to experiment with. Stay safe.
i would really like to see see this test repeated completely recapped u then maybe would could see a good comparison of the performance upgrade from recapping cause i know thise big red caps leak like crazy and also those old Malory filter can have been known to leak that bouncing around is a sure symptom i bet it might do 20hz then lol at least 25 lol
The brand name is "Rust-Oleum" and is called "Hammered". It comes in different colors but I almost always use grey. I buy mine usually at Lowe's but I think it is sold most everywhere.
@@raymondbeard8159 I had seen it in stores but I have a alum chassis so not sure it would stick without self eching primer I might just do my first amplifier bare alum then the second one I can always paint when my skills are better I have always repaired old amplifiers and have a bunch of parts transformers and output transformers and many chassis I’m looking for a strait forward hifi build for listing to music not sure if stereo or mono would be a good place to start I’m looking for a good schematic and pics to work off of like a older kit models of the past
it is made by RUST-OLEUM and is called HAMMERER. I buy it at Lowe's but I am sure Home Depot and others have it also. You can look at the top of the can and see the texture. It also comes in different colors. If you prepare the surface properly, it sticks really good and does not need a primer.
I believe I would have tried to offer to build him a power supply I built for him to get the original. I'm sure what you have built is new and better but you only get original once. Great buy for ten bucks lol
I have to agree with you. What I built is probably a higher current power supply and makes the amplifier perform even better than the original but, as you say, original is original... Personally, I don't think I would have bought the power supply without the amplifier (unless it was $2) so, I am thinking the other way around. Who knows why people do what they do....
I agree. We can't push tubes very far in a single ended mode. On the other hand, the 807, with the plate connection on the top, can run 750 volts on the plate and produce as much as 120 watts of audio for a modulator. The 1940 era 807 is as powerful as the modern day 6L6GC with the added bonus of being able to run them at that high voltage. The plate voltage on an octal socket has to be lower than a plate cap or arc over is likely from pin three (the plate) to pin 2 (the filament). There is a 12 volt filament version of the 807 called a 1625. The 6L6 is a powerful little tube especially considering the design has been around about 80 years.
@@ElPasoTubeAmps my design is coming along great Many hours of studying and testing before I assemble I have been learning so much my power supply is very massive and very heavy 🤓and too complicated but yet basic my next build will be more compact and less complex the type 83 rectifier has been working great many people say that tube isn’t great for audio and they say it has too much noise I haven’t had that problem maybe on the same chassis it would and input on that subject would be great
@@jimcatanzaro7808 Jim, There are a lot of people that say a lot of things that is just pure nonsense. They just repeat and add to what they have heard with no experience of their own. You 83 rectifier is going to work just fine. If they know so much about it they should give us at least a S/N ratio... Somewhere back in the days of the invention of the mercury vapor rectifier there was a problem with what was called "hash". It was primarily caused by poor design of putting the rectifiers too close to the RF section. (these guys were figuring it out empirically as we all do...) and 80 years later some people will tell us that MV rectifiers are full of noise. Well, they are full of BS because they don't have a clue. My builds and "designs" are often times large also but that is the way homebrew equipment turns out - we build with what we have and are not interested in saving a penny or two on mass production. Don't slow down because of the nay-sayers.
@@ElPasoTubeAmps I won’t stop ,I actually try not to even join groups anymore because of the snake oil negativity or jealously or whatever they’re mental illness is, thanks for your support and keep up your videos they teach me so much I just wish I had equipment like you and your massive stash of iron :) You teach very well and it’s very easy to understand you as a reg average American 🇺🇸
Sorry so long comment... I wasn't sure how to contact you my apology if too long. Not sure how my last name was made to gnome.. Funny but nity doing. I'd love to share pics of done of my fav pretty rare hear and parts I've never seen some till your video edp stuff like this pair of Round tub utc mains p's with paired chokesteral for audio specialized projects I think circa esrly 60s look just like ones I saw on yor transformer video. Maybe I'll put up my own RU-vid videos as you e inspired me. I wa just overexcited to see a matched pair to my wa1 807 one of fav tube although working with cv124 and other Kim less known tubes too. I gave other other wa-1 just not matched at all parts wise. Willing to trade or buy at restorable value. Also would be honored to have you even consider workimg on one of my 20 year plus planned projects getting rare parts for.., agSin cheers Mark!
Hi Mark, Sorry I haven't responded sooner. My grandson and I are leaving today for camping in New Mexico and taking my telescope to hopefully, get some good pictures of the moon. I am sure we can work out something with the Heathkit. I will write more in length when I get back. Stay safe.
Thanks for kind reply.. Wow my second most favorite thing in the whole world ( I can't do since my accident- but spent years teaching outward bound survivislism for troubled youth and college freshmen) up in Ontario canada( nothing in workd like mothers lights!) and since I was in grade school I followed Carl Sagan and used to have "star parties" where my parents would let us kids stay up late using our telescopes to look at binary star systems plantets etc. big hobby of mine. I'm Canada prolly like the desert- the light from cities was 80 miles away we weren't few olaces on earth total darkness on a new moon. I'm a writing now and I gave hard time explaining to people the magnificence of the purple pink Milky Way that fills the entire sky so brightly you can read a book by the light of the Milky Way- I never knew! And that as stArs come out one by one at a point I realized my first time out ( my family never camped) that the miracle is there's no darned to the sky! In fact there are more light points of stars than dark pints in between them. It was a natural religious experience for me to realize in utter darkness of night that there's more stars out there than dark space! Very cool you teach you grabdson this! I had a great loved G father But they all said csmping is a hotel with blavk and white tv. I made up for it diring my 20s spending about 1.5 years of my life removed so far from civikization ( kilarney provincial park) I'm Canada Georgian bsy if you google earth it. There's a mountain yarn lske that is called topaz lske it's a miracle of nature it's about 1/4 mile by 1:4 mile cirlce and its litersly a geode and inside all the walls and flor of the tarn lake are blue topsz not smokey crystals! And the park has lakes with visibility up to 110ft!! Hard to even describe. Water do pure you can drink it while swimming and a leaf on bottom 100 ft down looks just arms reach away but swim 30 ft dien still arms reach away. Clear blue tropical looking water. My most favorite park in the Americas I've found! Have fun with your grandson! Hopefully you see some great stuff. If you haven't left yet consider bringing a metal detector or maybe next time as deserts are often full if meter orices a few shows on this now but I don't watch much tv anymore! There previous also worth money but I know as a kid and adult too searching for meteorites would be a blast! Good luck enjoy camping! Again prolly only thing I enjoy more than audio if in ablevto get friends to help me carry stuff in as I used to hike 100 pound packs in 40 mile gir liar trail or canoe blu dry waters by Minnesota but now I'm only able to carry ten lns. No complaining though I've seen so many bestifull northern lights , meteorites and one flew litersly hundred yards above our heads thought it was a firework but we were 50 miles from nearest road car anythjng! I'll hope something magical hapoens that only you and grandson get to see I have lots of such memories with my grandpa he's pased on now but it's extra special as I was adopted at 6 weeks old and he treated me as almost more of a grandkids than his own - we were close buddies!
@@freelancewritermark4794 We do have a metal detector and I will definitely be taking it next time we go out. Thanks for mentioning it. I took our conversation off RU-vid to personal email. You should have it by now.
I did this and documented it for a McIntosh MC40 a few years ago. Here are the results. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-e9eiETiSGx4.html Unless there is an actual "bad" capacitor, this performance gain is only in our minds, in my opinion, because we expect it to be so much better. Real measurements tell a different story.
Never thought of it that way but I would classify amplifiers in the 250 volt range (SE or PP) to be in the five watt range, up to 450-500 volts, medium power amplifiers up to 50 watts, maybe a little more, voltages in the 750-800 volt range 100+ watts amplifiers and 2500 and higher voltages in the KW power range. Transmitting tubes need 3500+ to be in the two KW range.
ElPaso TubeAmps iv built two Cass A SE 24V Nelson Pass, Amp Camp Amp @ 15w mono blocks. One Pete Millett starving student hybrid headphone tube amplifier using 48 V SMPS power brick. One JLH amp 100w SE 42v I think Blue Glow Electronics , Mark RU-vid channel has produced one of the finest instructional high voltage tube amplifier builds I’ve ever seen that will probably be the first high voltage tube amp I build.
