Proposal / Solution for StevenZ's Amp Situation......

Status
Not open for further replies.

dowto1000

Junior Member
Since I was censored from StevenZ's amp thread, I will start my own. Forum members probably are very unhappy with your amplifier build problems. I know I am, to say the least. So........ to serve you, I will " step up to the plate".

StevenZ, relax some, I have a proposal for your consideration. If you can wait till February 2018, ( when I have some time ) I will re-DO your amp with NO labor charge at all, only parts costs ( which we can economize upon ).

We would do a direct coupled 2A3 amplifier circuit, REAL triodes StevenZ, imagine THAT , as inexpensively as I know how to do, so your amplifier problem will be optimally resolved, long term.

We could re-use your pretty chassis. Perhaps even re-use your output transformers ( especially if they are 6K Z or less ).

We could re-use the 12AX7 tube sockets and tubes !! The high gain ( mu of 100 times ) 12AX7 is LOTS of FUN to listen to in our 2A3 DC amp implementation, mentally-engaging to hear.

Since 1984, I have on my shelf, a "cool" looking vintage power transformer, nicely enclosed / potted, that is a fabulous piece. It weighs sixteen pounds, made by ADC ( Audio Development Corporation ) for B+ only. It is rated 115 VAC to 370-0-370 VAC..... at 750 whopping milliamperes. This power transformer's total high voltage winding ( 740 VAC, end-to-end ) measures ONLY 18.20 Ohms, which is superbly-low.

Since the amp proposed only draws about 120 milliamperes, a 750 milliampere rated power transformer will LOAF, and as a by-product, provide top-notch bass, electronic self-regulation, and superior inner-definition of all the music.

In preparation for this post, I load-tested and measured this power transformer yesterday. A change from zero load, to a full 120 milliampere load, is only a 0.6% drop in the secondary's VAC. ( 0.994 of the original NO-Load measurement.) Fabulous natural stability !!

I can sell off your existing Hammond ( 54 Ohm DCR / 287 milliampere rated ) power transformer, and that ineptly-chosen, very nasty-to-hear 82 Ohm Hammond choke, to defray the value of the vintage ADC 750 mA. power transformer. ....18.2 Ohms !!

You will need to go, out of pocket, for four small filament transformers. They will go below deck. One for the 12AX7 filaments. One for the 5U4GB tube rectifier, and two, one each for the 2A3 filaments. Maybe $75 or so.

I will apply a unique and effective power supply design, refined over the past 35 years. We would use a LSES supply ( LOW STORED ENERGY SUPPLY ). It is a special ultra high performance L1/C1/L2/C2 B+ filter configuration to the 2A3's, ( L is a inductor or choke, C is a capacitor ).

The first choke, L1, will be a single 6 Ohm DCR Hammond 159ZA, capable of 1,000 milliamperes. The L2 chokes will be " split" ( fed by C1) as one L2/C2 for EACH 2A3 . The two L2 chokes will measure 10 Ohms DCR each, lovely sounding chokes, no longer available / made.

Total choke associated resistances will be only ( 6 + 10 ) 16 Ohms to each 2A3 channel. Versus 82 Ohms ( or more ) most people UNconsciously all use. Sixteen Ohms is simply outstanding to hear, with a 2A3 tube !!! You will be out of pocket $76 for the three new chokes, and I will convert their lead outs, from their stock, usually 22 AWG, to Mil Spec 14 AWG high quality / wide-band lead wire, for free.

Quality resistors will be $60.00 for both channels. NO PC boards, point to point.

We would ONLY use a DIRECTLY heated TUBE rectifier, because that simply sounds the best of all options. 5U4GB, $15.00.

I'll provide the amp's wire internal, no cost, all top quality Military Specuification, super high quality, various gauges as needed, just as I do in my own builds.

OUT OF TIME....finish tomorrow ..


Tommorow is NOW !!

I have vintage ceramic tube sockets, USA classic parts, for the two 2A3s, and the rectifier tube, which I will donate.

A SET amp I might do will have NO electrolytics , use all quality / good sounding film caps. Every capacitor position ( about 11 in a stereo amp ) , will have multiple bypassing, to allow the SET to play WIDEBAND. This means about 34 film caps. I'd estimate, when not using boutique caps, we can get it to within 80% of the best possible botique caps' sound, for $200. That is 5 to 7 % in the cost, of what " I " would like to use, boutique / quality wise. Five to seven percentof the cost, getting 80 percent of the results, the performance, is A-OK in my book !!

( We have today, industrial film caps, typically made by WIMA in Germany, that, carefully selected, are extremely high in performance. Industrially priced. I'd know what to order. )

The amp uses a modern day variant of the 1929 Loftin White direct coupled circuit. No solid state parts in it. Tube rectifiers....directly HEATED tube rectifiers, which sound the best. 5U4GB is about 15 dollars. Hardware, nuts, bolts, mounting terminals ( point to point ) is another 30 dollars.

No coupling caps, G-d AWFUL things to use in a circuit. Just half a 12AX7, directly coupled to the grid of a 2A3. KISS,... KISS rules !!

One has to be smart to chose a real triode and NOT ever a triode-connected-pentode. Why?? It sounds better, always, that is why...good enough reason to discard second-best designs. " There is no substitute................ for the real thing. "

Amp will have a high performance fully-shunt-regulated B+ supply to the 12AX7 driver stage, ( which hardly any one else ever does ) - a BIG plus. Puts out about 3 Watts per channel, and will play DYNAMICALLY like you and others have never ever heard before.

Nothing known to me personally, anywhere in audio, can out-do this basic simple circuit, as it would be implemented, when used on high efficiency speakers. I am building my own monaural amps, using JJ 2A3-40s, over 12- 2017 and 01-2018. Yours would be after mine. Your call StevenZ, I am willing to serve you, if you are able to be patient and wait 60 days. Looks like parts cost is $476, plus shipping TX to MO and back to TX.

Dowto1000

PS:

Regarding 2A3s: I would like to see someone on this Forum also " step up to the plate" and offer either one, or both 2A3's for StevenZ to simply borrow for 6 to 12 months. I have no old biplates left. The tubes would loaf, 10.5 Watts design center on a 15 Watt rated plate. When StevenZ financially recovers, he will go out and get JJs for himself, and send the borrowed tubes back to Forum Members. One or two would be fine!! Who reading this, will help the fellow ?? He'd appreciate the loan, and so would I.

Thanks, regards,

Dowto1000
 
Last edited:
Jeff, this thread is your show and I won't intrude. However, you have presented your statements as being the gospel, so I must comment.

There is no scientific evidence that the presence of a cathode degrades the performance or sound of a tube. Such judgments are purely subjective. A cathode type rectifier is as capable of delivering the goods as a directly heated type. Rectifier tubes do not have a "sound!" Differences attributed to such can be quantified by measuring the B+ voltages delivered- if one tube has a radically different voltage drop from another, operating points can alter enough to affect the sound. That is what people are hearing. This is easily confirmed in blind listening tests.

As to triodes with a cathode or triode strapped pentodes being inferior to directly heated types, that too is purely subjective. And, it's really an impossible comparison to make as those making such claims usually do so with amps which are totally unrelated. When someone tells me that a particular DHT amp sounds better than a particular triode strapped pentode or cathode type triode amp my first question is whether the harmonic characteristics are identical (basically an impossibility). And my second question is whether the output transformers are identical. And so on. You get my drift. By the way, since you like the 2A3, take a look at the triode curves for the 6Y6. You will be very surprised.....

I won't say any more but would feel better if you could at least say "in my opinion" when making these statements. So much in audio is totally subjective that to do otherwise is a disservice to those who are unfamiliar with tube electronics and want to learn.
 

dowto1000

Junior Member
Yes, of course, ALL I write is in my opinion. Many other good builders will have a similar listening experience!!

Jeff, this thread is your show and I won't intrude. However, you have presented your statements as being the gospel, so I must comment.

There is no scientific evidence that the presence of a cathode degrades the performance or sound of a tube. Such judgments are purely subjective. A cathode type rectifier is as capable of delivering the goods as a directly heated type. Rectifier tubes do not have a "sound!" Differences attributed to such can be quantified by measuring the B+ voltages delivered- if one tube has a radically different voltage drop from another, operating points can alter enough to affect the sound. That is what people are hearing. This is easily confirmed in blind listening tests.

As to triodes with a cathode or triode strapped pentodes being inferior to directly heated types, that too is purely subjective. And, it's really an impossible comparison to make as those making such claims usually do so with amps which are totally unrelated. When someone tells me that a particular DHT amp sounds better than a particular triode strapped pentode or cathode type triode amp my first question is whether the harmonic characteristics are identical (basically an impossibility). And my second question is whether the output transformers are identical. And so on. You get my drift. By the way, since you like the 2A3, take a look at the triode curves for the 6Y6. You will be very surprised.....

I won't say any more but would feel better if you could at least say "in my opinion" when making these statements. So much in audio is totally subjective that to do otherwise is a disservice to those who are unfamiliar with tube electronics and want to learn.

- - - - - - - - - - - - -

How does your post help StevenZ??

He had built the amp design you endorsed and / or defended, and its a sonic DUD, which is exactly what I said it would be, and StevenZ is out a whole lot of money, and can not afford to make a second mistake .

Now, you are trying to tell us all that extra elements added, physically positioned inside a tube has no effect, no consequence....sonically.......?? ' Sounds impossible to me.

Maybe one day, you will gain experience, listening experience at a high level, and become enlightened ...or, maybe you will flounder, for the rest of your life !! Many people do.

So, getting back to my intent, will anyone loan StevenZ one or two 2A3s, IF he decides to convert his amp to a REAL triode amp?

I'll do the labor beautifully, many hours for free, execute the amp, just need some parts help to keep his costs down, till he gains listening experience, and confidence with / in, the whole shebang.

Dowto1000
 

TubeHiFiNut

Administrator
Let's keep things civil.

Everyone has their own listening biases and technology beliefs. We all like different stuff - and that's not a bad thing.
 
Come on Jeff- we New Jerseyans need to stick together and not argue!

As THFN aptly pointed out, it is impossible for a consensus to exist when it comes to the auditory or any of our other senses. There's absolutely nothing wrong with Claus' design. It's simply a matter of Steven not finding the sound of Claus' EL34 implementation to his liking in his particular application. It could be a synergy issue with his speakers, or Radu's implementation which is not exactly per Claus' circuit. If someone tried this amp on a pair of Klipschorns, or other high efficiency speakers, they may find the sound to be exquisite. Steve Deckert's EL34 amp is reported by some to be phenomenal. I might hear it and run out of the room. The same goes for SETs of any kind. I know guys who find the sound of the latter to be offensive. Others find the sound of tubes in general to be inferior to their favorite SS equipment.

Again, I'm pointing this out for the benefit of followers of this thread who have no tube experience and want to learn. I am in no way insulting you or your beliefs. The bottom line is that a person needs to hear an amplifier in their system in order to make a judgment as to whether it will deliver what they desire. I consider my amp designs to be the best in their class, as do you. I can't imagine that every person who hears them would agree. If an amp existed which every person agreed is the best, the hobby wouldn't be much fun.

Lastly, in regard to your comment about my presumed lack of experience with high level enlightened listening, I can only say that you are unaware of my background and credentials. Let's leave it at that.
 

StevenZ

Pending Gold Star Member
I've been away for a few day and just saw this post. I want to thank Jeff for offering his help and opinions as I do appreciate the offer to convert my amp to 2A3. As for tubes, I do have a buddy locally that can lend me some 2a3 tubes for a little while so that wouldn't be an issue.

Will be in touch.
 

TubeHiFiNut

Administrator
Jeff....It like many here have been trying to convey to you. You get more and better results with kindness and by being friendly than by posting comments like this one:

Maybe one day, you will gain experience, listening experience at a high level, and become enlightened ...or, maybe you will flounder, for the rest of your life !! Many people do.

My advice to you is to always take the high road instead of throwing out comments like the above.
 

TubeHiFiNut

Administrator
Come on Jeff- we New Jerseyans need to stick together and not argue!

As THFN aptly pointed out, it is impossible for a consensus to exist when it comes to the auditory or any of our other senses. There's absolutely nothing wrong with Claus' design. It's simply a matter of Steven not finding the sound of Claus' EL34 implementation to his liking in his particular application. It could be a synergy issue with his speakers, or Radu's implementation which is not exactly per Claus' circuit. If someone tried this amp on a pair of Klipschorns, or other high efficiency speakers, they may find the sound to be exquisite. Steve Deckert's EL34 amp is reported by some to be phenomenal. I might hear it and run out of the room. The same goes for SETs of any kind. I know guys who find the sound of the latter to be offensive. Others find the sound of tubes in general to be inferior to their favorite SS equipment.

Again, I'm pointing this out for the benefit of followers of this thread who have no tube experience and want to learn. I am in no way insulting you or your beliefs. The bottom line is that a person needs to hear an amplifier in their system in order to make a judgment as to whether it will deliver what they desire. I consider my amp designs to be the best in their class, as do you. I can't imagine that every person who hears them would agree. If an amp existed which every person agreed is the best, the hobby wouldn't be much fun.

Lastly, in regard to your comment about my presumed lack of experience with high level enlightened listening, I can only say that you are unaware of my background and credentials. Let's leave it at that.

Spot on post, @BH :)
 

dowto1000

Junior Member
I've been away for a few day and just saw this post. I want to thank Jeff for offering his help and opinions as I do appreciate the offer to convert my amp to 2A3. As for tubes, I do have a buddy locally that can lend me some 2a3 tubes for a little while so that wouldn't be an issue.

Will be in touch.

StevenZ,

It would not be hard to do the conversion, since the chassis is already MADE for a two stage stereo amp, I would have VERY little to mess with, as far as constructing a good looking chassis,... its already done.

I am also guessing that the Output Transformers will be 6K or less. It looks like a Lundahl output, associated with the goofey original design, ( in one on-line write up ), was rated at 3 K, which is FINE for a 2A3. I am comfortable with 6K or below, and lower than 6K is better. The rest of the amp will be so well designed and executed, that a non ideal output transformer impedance will not be critical to the overall listening result.

This ADC 750 milliampere-rated power transformer is RARELY ever seen or used in audio, and it is a BEAST !!

Generally, the lower the DCR ( direct current resistances ) of a power transformer, the better the stability of the audio presentation. 18.2 Ohms across an entire high voltage winding is just superb for stability. I'm using 54 Ohms in my next build, and 'wanna hear 18.2 vs 54 Ohms, IF we do this project, just to see ( hear ) if I need to go lower in my own custom power transformer designs.

The uber-low 6 and 10 Ohm L1 and L2 chokes " makes up " a lot for a power transformer's higher DCR, since the chokes are " driven " elements in the B+ filter to the 2A3s. But ....lets not worry too much about B+ filter design theory. I've been pondering and working on that for the last 35 years.

I am just guessing, it may be 20 hour's of labor, to remove the existing circuit, and point to point implement a new Direct Coupled all-triode one. I could be wrong on the time needed, but generally speaking, it is FUN to anticipate the result, and to build something you like and have confidence in !!

Dowto1000
 
Last edited:

dowto1000

Junior Member
Jeff....It like many here have been trying to convey to you. You get more and better results with kindness and by being friendly than by posting comments like this one:



My advice to you is to always take the high road instead of throwing out comments like the above.


I DID take the high road, I was smart enough to see that the original design was terrible, and I ( alone - the lone voice in the wilderness ) spoke the truth about it.

I also see, from BH's various comments, MANY MANY glaring errors, and I spoke the truth about what I thought of his reasoning and lack of listening experience. I did not write in a nasty demeaning way, and certainly, nor did he to me.

Lets leave it there. BH and I can gracefully agree to disagree.

Dowto1000
 
Last edited:

TubeHiFiNut

Administrator
I DID take the high road, I was smart enough to see that the original design was terrible, and I ( alone - the lone voice in the wilderness ) spoke the truth about it.

I also see, from BH's various comments, MANY MANY glaring errors, and I spoke the truth about what I thought of his reasoning and lack of listening experience. I did not write in a nasty demeaning way, and certainly, nor did he to me.

Lets leave it there. BH and I can gracefully agree to disagree.

Dowto1000

Jeff,

What I am trying (and, evidently, doing a terrible job) to convey to you is that there is no "one truth" in audio.

Whereas the amp that @StevenZ had built was not to his liking, there are other folks, from what is on the Internet, that do like it. Again, no "one truth".

As I have stated before, it's not what you say, it's how you say it. If you don't think that this is insulting and condescending: "I also see, from BH's various comments, MANY MANY glaring errors, and I spoke the truth about what I thought of his reasoning and lack of listening experience", then I don't know what to tell you.
 

Audionut

Next Round Is On Me
The proof is in the pudding Jeff. Get in there and let your work speak for you. I appreciate you offering to help StevenZ too. Using a little honey versus vinegar will make your message more palatable to the beehive here.
 

dowto1000

Junior Member
It is indeed. And please keep in mind Rule # 2, if you again decide that yours is the only right way in an audio discussion.
It is indeed. And please keep in mind Rule # 2, if you again decide that yours is the only right way in an audio discussion.
It appears that @StevenZ is well on his way to resolving his concerns with the EL-34 SE amp:

My response to "PaulatBottlehead", a HI Fi Manufacturer, was rather elegant. very gentle - intelligent and thoughtful on my part IMHO. Please do re-read his wording,\ !! Then, Forum Owner, look at my tactful response sir !!

I am rather surprised that you would post what you did. I am also surprised, your Rule #2, that you would use the term " asshole" on a Public Forum, and, that you would infer I was one.

If I feel, ( as a result of my experiences, and 35 years of work ), that a certain way of doing something is optimal, and I wish to share it with others in the hobby, there should be NO restrictions for me to state that. Just realize, I always discuss things from my perspective, which is comprised of a different set of audio experiences than any one else's.

I also find it rather extraordinary, that when it was looking very bleek for StevenZ, I alone stepped up to the plate to tangibly help him rebuild his amp for free. Anyone can write and post, its easy and cheap to do, but I ( alone) committed to a good twenty hours of spare-time labor, to help him out.

I don't even know the fellow, but I sensed he was a really good guy, and was willing to go to bat for him.

Dowto1000
 
Last edited:

JohnVF

Administrator
Staff member
There is a difference between stating and defending a preference, and stating a preference while alluding to the idea that having any other preference than yours is a personal failing only possible because somebody doesn't share your experience and ears, that you alone possess.

We have been quite tolerant here. Questioning moderation in opens forums is often a career ended for posters in other places.

Your reputation on other forums has preceded you here. Unless you learn to behave like a respectful human being who tolerates the simple fact that other posters, who through their own VAST experience, have arrived at opinions that differ from your own, your fate here will mirror that of the other forums that grew tired of being treated like they've been touched by the hand of God merely by having your presence gifted to them.

I hate to post this in the open forums but this problem persists despite repeated attempts by others to curb it otherwise. It's not hard to be respectful of the opinions of others. You don't hold the keys to Heaven, there are many many ways in, and yours is only one, even if its completely viable.

We have one basic rule. Don't be an asshole. We've made it that blunt on purpose. Why? Because it's NOT HARD TO OBEY such a blunt rule. And yet here we are.
 
Status
Not open for further replies.
Top