ToolShedAmps
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Posts posted by ToolShedAmps
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Good God…. You are missing the point. This is musical. I’ve tried everything from gyrator, J-Fet CCS, tube CCS, inductor, you name it to load my voltage amplifier stage/s…. this sounds BETTER to my ears. And they are in fact, what my customers rely upon.
Please don’t turn this thread into some sort of inane engineering pissing match. I have no idea what you think you need to prove to anyone. Armchair braggadocio and looking down ones own snoot at the effort of others is seldom attractive.
It’s my amplifier I will build it as I see fit. My customers truly enjoy the music that it makes. 107…. and counting.
And really, that’s all that matters.
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1 hour ago, mikebse2a3 said:
I find the obsession some people have with “neat pleasing to the eye wiring style” to be misguided and often sacrificing the benefits of 3 dimensional wiring of good point to point designs that can look messy to an untrained eye.
miketn
Here are a few examples of what my products look like "under the hood"...... Hmm....... can't shrink them down far enough to get three of them on here.
Instead, I'll post a link to the gallery on the website for these pics.
https://www.toolshedamps.com/inprocessconstruction
The wiring methodology is my own, it does not emulate anyone's style. I'll be adding construction pics as time allows to this gallery.
And, yes, nothing is as it is accidentally. All of these choices have been deliberate. Everything has been carefully selected based on the tonal colors it adds to the finished piece. These selections cannot be quantified by math alone........... after all, a 220R/1/2W resistor is a 220R/1/2W resistor isn't it? Whether it's carbon film, metal film, carbon comp, thin-film, or tantalum doesn't matter........... or does it? Even if they measure the same? Hmm............? This then is a rhetorical question, of course they all sound different, despite measuring the same. The human ear doesn't lie, and it is IN FACT the most important development tool we have. Because once we've crossed our "T's" and dotted our "I's", they are the tool that can mean the difference between a good amplifier, and something truly magical.
Cheers!
Matt.
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1 hour ago, captainbeefheart said:
There is really no need to have a 'mentor' for amplifier design. All that is needed is good foundation of electrical engineering and time. Study and analyze circuits, build them and test them, listen, over time you make your own conclusions and not someone else's. You do not need a college degree although having a solid understanding of mathematics is extremely useful and will make life a lot easier.
It really boils down to effort and time, you get out what you put in. I never had a mentor of any sort, just lots of books and many files of circuits to study. Then the time to build circuits and test them, listen and evaluate, this is how I made correlations between what I am hearing and what I am measuring. If you learn from a mentor only you not only pick up their good habits, you may also pick up their bad habits as well.
As for this.......... I somewhat agree, you can find and read, and disseminate as much information as you can get your hands on, develop a more-than-passable working knowledge of advanced mathematics, crawl down the rabbit-hole of endless forum "suggestions" until you become part of your computer chair, then order up $20K worth of resistors, caps, power transformers, chokes, output transformers, signal tubes, power tubes, rectifier tubes, vr tubes, solder, switches, tube sockets, wire, etc........... and solder together all of the circuits you've read about and see how they sound................. so about 5,000hrs and two marriages later you can be somewhat satisfied? Maybe if it were a hobby. Certainly not the suggested methodology if you've got four kids to feed.
I feel eternally blessed to have the help I've been given...... and express it every chance I get. The "help" is usually in the form of not wasting precious time chasing a topology that's been tried by others and is ultimately not good enough. This kind of direction is most welcome.
Bad habits..................... Hmm.... well, everyone knows that audio designers have the capacity to grow like any other human being. Changing one's perspective is part of the human condition. I welcome change................ as long as it sounds better.
My recommendation for those wanting to DIY, is to find a topology that several people have used, build from a valid schematic, then rub on it till it shines. You'll learn much in the endeavor. I absolutely believe in empirical evidence to support what I'm hearing. Word of advice: buy the best iron you can afford. There is a difference.
Good Luck!
Matt.
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2 hours ago, captainbeefheart said:
That's great thank you.
I would change the specs on your website to what you just wrote here. Your website is misleading, it says no more than 1% THD and people are going to think that is at full output if not otherwise stated. This is the same thing that was just happening to the Crimson 275, they mislead on the specifications which got a lot of people fairly upset the product was sold under false pretenses.
Someone has to keep the manufacturers honest, hopefully you understand and not take this personal.
Noted, and adjusted....... FWIW, you'll notice that Silbatone doesn't list ANY specifications for the amplifiers on their website....., and believe me when I tell you that JC and Joe know what they are doing.
Suffice to say that the amplifier sounds glorious, even at full power, banging out Highway Star at an absolutely absurd volume level, only fit for a teenager!
Cheers!
Matt.
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59 minutes ago, Curious_George said:
300B @ 1% THD+N
This measurement was made of 2 different sets of 300B's with about 200 hours on each set. A newer set of 300B's (with only about 75 hours on them) had much higher distorion and lower power output based on 4 Watts as a refererence.
Have you measured the new W.E.300b at 1W ? It's an eye opener for sure, possibly due to the new proprietary filament coating. None of the other 300b's are even close, although among the "other" high-end brands (EML, KR, Takatsuki), the Elrog ER300b (possibly due to the Thoriated-Tungsten filament) is closest, full disclosure, we have no EAT 300b to evaluate. Also, the Transcendence Amplifier uses a higher-than-typical primary on the output transformers, this helps to keep distortion lower at higher power as well. The amplifier was designed for musicality, not power. If a 3K primary OT was used at this operating point, the power would be in excess of 11W. This said, it really is a "dance" that numbers alone cannot quantify.
Matt.
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10 hours ago, captainbeefheart said:
I had some time to read through the build thread and a couple reviews which leaves me with more questions.
I appear to be wrong as these are open loop or zero feedback amps? Which makes sense that you are triode wiring the E180F and D3a, there isn't enough gain for any feedback. E180F triode wired is probably around 32x gain and the 300b is roughly 3.8x. This jives exactly with the 14db gain of your amps and the need for 2.23v for full output. Nice trick to keep noise low is to have a low gain amplifier for high efficient speakers, downside you may need a preamp to reach full power.
I guess my question is now what is the output power of the 300b amp measured at 1% THD? After some quick calculations my guess is the amp is 1% THD at 1 watt output. There is absolutely no way an open loop 300b amp will produce 7-8 watts with only 1% THD.
Yes, 0.93% @ 1W w/1KHz sine-wave. No "global" NFB. However, still less than 5% THD at full power. And, yes, carefully selected operating points are key. The C3g driver stage is even slightly more linear, w/distortion slightly lower. However, distortion isn't everything, the design goal was musicality, everything else seems to fall into place within that context given sound engineering practices, a little luck, and mentors such as Gordon, Herb, JC, Joe Roberts... and countless unnamed contributors to MJ Audio magazine over the years.
IMHO, it really is about that 1st watt (or 700mW if you've got K-horns or LaScala's)....... or really anything above 93db efficient. Although headroom is nice. 99% of my customers, family, friends, etc. critically listen with peaks at maybe 88db. Maybe we are all just getting old, who knows.
FWIW, the final amplifier design didn't happen in a vacuum, Gordon and I designed the Iron-Coupled DHT Line-Preamplifier to compliment the amplifier w/approximately 5db of total gain, the 01a and 71a's operate right in their own "sweet-spot" allowing the entire volume control to be used, and just enough gain to drive the amplifier to full output with the "industry-standard" 2v input.
A phono gain amplifier is in the works for this calendar year. This piece will complete the "Trifecta" for customers (and myself) that just want to stop buying gear and just "enjoy the music". Again, the design goal is ultimate musicality, not just vanishingly-low distortion figures. Gordon has, separately, finished his penultimate DAC, the Pelham, which also uses the 71a DHT in it's gain stage for customers digitally inclined.
Lastly, final voicing is being done to the "50" version of the Transcendence amplifier. It uses a choke-loaded driver stage with the EXCELLENT Silk Audio grid choke on the 50. Jury is still out on the input transformer......... it may or may not use it.
Cheers all.
Matt.
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Howdy all, tipped to this thread by a Klipsch customer in Des Moines................. Been busy.
A new review dropped either late Saturday or early Sunday over at Part-time Audiophile............ here is the link in case you have interest in reading.
https://parttimeaudiophile.com/2022/01/28/toolshed-amps-transcendence-300b-amplifier-review/
Although the reviewer used a single, wide-band speaker, you all know I'm more of a Klipsch/Altec guy. Different strokes for different folks.
It's all good.
No hard feelings with Klipsch management about the Cary thing either........... Billy is a great guy and Cary has some decent product. Business is business.
Cheers!
Matt.
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Hmm..... If I had to guess, Cary Audio is tired of seeing my P.W.K. Edition, Euphoria Stereo 2a3/45 in the Klipsch Heritage ads......., including the pic on page 158 of this year's Music Direct catalog of the new AK6.
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12 minutes ago, mikebse2a3 said:
Beautiful work on the amps and awesome to see someone doing what they obviously love.🙂👍
miketn
Thanks Mike!
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This just in........... and final voicing with the Klipsch Reference HP-3's....
https://twitteringmachines.com/review-toolshed-amps-darling-head-amp/
Cheers!
Matt.
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7 hours ago, Jeffrey D. Medwin said:
Looks impressive if one didn't know better. There are some things you could do to vastly improve that build .
Jeff........ my customers listen with their ear-holes, not their eye-holes, and you know what they say about the other-holes, like cowboy hats, everyone has one.
For the life of me I can't figure out how to find enough room in my amp chassis for that 8 AWG wire, or the 18 Million Watt-capable coupling caps. But come to think of it, I suppose I could VASTLY improve this build if I wrap the whole amp in silver and claim bandwidth is DC to Light.
Matt.
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Oops! Almost forgot the "gut-shot"........
And, YES, those are massive, Magnequest output transformers.
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54 minutes ago, Jeffrey D. Medwin said:
Basically, always only a two-stage tube SE amplifier, first tube MUST be a Mu of 100 triode with a Shunt Regulated B+ supply, directly coupled with heavy pure silver wiring to : ( one of only three Finals tubes ) :
the grid of a JJ 2A3-40
or a 6005 ( very low Power, triode-connected ),
or to the grid of a KT-88 run as a Pentode with its own separate Shunt Regulated B+ supply for it's Screens.
Always Zero Feedback. LSES power supply, which stands for Low Storage Effect Power Supply, ala the Serious Stereo 2A3 monoblocks. ( Look them up on line. 'Best commercial amps, sonically and in design, I know of . )
I use only directly heated tube rectification, L1/C1/L2/C2 B+ filters, with all power supply filter inductors VERY importantly being 10 Ohms or less in DCR, and all Cs being Film Caps only, not exceeding 50 uF per location ( a FAST reacting supply ). I also ( uniquely ) bypass my C1 and C2 film caps - going to the Finals - with GTO film caps, capable of doing 1.500 Amperes peak instantaneous.
Careful attention is paid to wiring, using either multiple duos or "trios" of Mil Spec ( 12+12+14 M22759/11 on grounds ) or multiple runs of Polished Cardas SIlver 19 AWG in a few locations.
Very careful attention to layout. RCA jacks always within 2 inches of the grid of the Input / Driver tube, two Cardas Silver runs for this short two inch input tube run. Direct Couple uses three Cardas Silver runs in parallel.
All my tube op points are VERY carefully chosen to conservatively run a tube, for maximum sonic performance and maximum life span. I use Golden Ratio plate dissipations, 62%. So, a 10 Watt rated plate I will run at 6.2 Watts dissipation, by reducing current across the tube, but not necessarily voltage across the tube.
I make extensive use of multiple film cap bypassing in key capacitor positions, values selected by ear. I also design for maximum DYNAMIC contrasting with my amps.
Here is a two stage stereo 6005 prototype I did in 2018, plays lovely in its ( very low - less than one Watt ) output power range. 14 gauge welded steel chassis, powder coated. The 2A3 Finals tube will be 2 or 3 watts of Power Output, the KT88 5 to 7 Watts of Power Output.
Jeff
Ahh............... ya, I might know a thing or three about 2-Stage, Zero-Feedback, PTP-Wired, 2a3 Output, Single-Ended, DHT Amplifiers..........
Matt.
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On 3/6/2019 at 4:14 PM, Jeffrey D. Medwin said:
Comment : When things sound wrong, it may be the result, not of the inserted piece, but a bogus piece in front of it. AMPS , Les, are the biggest turkeys of all, NOT speakers. Maybe the wide bandwidth wiring was allowing you to hear the nasties in your amp, like a electrolytic capacitor. The amps I build all my past 4 decades go FAR FAR beyond the Dennis Had " Inspire" - or whats out there and commonly used,. You may have heard the wire " right", but the problem was not the wire!! That is my point to you. In the finest of systems, nothing beats pure silver, Siltech, Ensemble, etc., but thats a $10K bill to do it right.
Mr. Medwin, would you be so kind to enlighten us with a few pics and verbiage of YOUR amplifiers to which you speak?
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Now if I could buy output transformers wound with 8 AWG, I'd be in business!
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2 hours ago, glens said:
As opposed to Fortes III and tubes? Or is this a one-sided viewpoint? If so, it's worth no more than mine. OP is looking for directly-comparative opinions. So far the reply by CECAA850 on the first page comes to mind as the most pertinent. kink56 also had an applicable opinion on the first page, but he was wrong (
).
I might as well chime-in, although the Forte III is a mighty fine speaker (slightly smoother through the mid-range than the Cornwall III, IMHO) they require careful setup to get the passive radiator to work properly..... you CANNOT push them up against a wall. Additionally, they simply cannot compete with the Cornwall if you consider a "life-sized" rendering of instruments on the sound-stage important. They play "bigger", there's something about a 15" woofer that a 12" (even with passive radiator) just can't quite match.
As for the Chorus (either I or II's, I have owned both) despite their sensitivity, they are a far more difficult load to drive with tubes than the Cornwall. And of course with the same placement requirements as the Forte' (I, II, or III's).
That said, if the poster purchases either, he'll be grinning from ear to ear.
Matt.
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Go with the Cornwall III's, I absolutely LOVE mine and they pair incredibly well with valves.
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Hmm....... much has been written by men without ears......
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12 hours ago, mopardave said:
Do different rectifier tubes change the tone of an amp like preamp and power tubes?
In most cases, the difference you hear will be due to a change in the operating point/s of the amplifier/pre-amplifier with a rectifier change as the amount of voltage dropped by different rectifier types varies.
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1 hour ago, Marvel said:
I'm good for the down to earth end... I can't afford high end.
I have some Electro-Harmonix 2A3 EH Gold that work very well in my Moondogs. When I bought thiese amps they came with a pair of Sovteks and the EH. Had these for about 10 years I think and haven't replaced them yet. The EH are definitely better than the Sovteks, at least in my amps.
@ToolShedAmps Matt, the EML looks great but is, unfortunately, way past my budget. I was able to hear a pair of the new WE 300B tubes in a new WE amp with SS rectifier and printed circuit design.
I felt like my amps with the EH 2A3s sounded as good, but the listening environment wasn't as good as my own living room. I'm sure the higher priced tubes can bring something to the table but I have my limits. 🙄 Except I am looking for another pair of GZ37s, realizing that might hurt a lot.
Bruce
Yep, the GZ37's are going for over $100 each now, luckily decent 5U4g's are still to be had for half that. You might want to try the JJ 2a3/40's when budget allows, they are very well made and sound very nice.
Matt.
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1 minute ago, NOSValves said:
Mike is a true artisan when it comes to winding transformers. I've dealt with him a number of times off and on for almost 20 years now. He always delivers top quality!
Agreed! His build-quality is second to none, I've got a couple pair to get started....
Check this out, solid brass channel frames! Absolutely massive!
I'm so excited and feel honored to be given the opportunity to use his transformers in my Euphoria 2a3/45 amplifier.
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1 hour ago, Marvel said:
Nice, can't wait to see more. My Welborne Labs Moondog 2A3 amps use Magnequest trannies. Really good for the bottom end.
Bruce
Wow! NICE, GZ37's! Give my friend George a call @ www.tubesusa.com/ELtubes.html for a pair of EML Mesh-2a3's
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7 hours ago, Schu said:
Any recommendations on a 2a3?
Check this out.... no tube sockets sandwiched between transformers....
also, new development, now available with Magnequest output transformers.....
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On 12/26/2018 at 4:57 PM, ssh said:
Someone got a very special surprise for Christmas. I hope to hear it soon.
SSH
Thanks Steve, let me know what you think.
Merry Christmas.
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Western Electric wants to know if you want them to make tubes other than the 300B
in Talkin' Tubes
Posted
I asked for 274b, 350b, 437a and 417a............... pipe dream, most of them. My guess is that they will try to fill the "guitar" amp tube vacuum. 12_ _7's and a power tube of some sort, unfortunately, probably not the 350b.
Anything would be welcome.