New Design, SE 6005 Directly Coupled Audio Amplifier

[drlowmu]

here is the ugly ducking...1KVA

View attachment 66601

View attachment 66602

Respectfully, IMHO / IME ,

1 KVA is certainly a degrade VS plugging any amp ( I would use ) directly into the wall !!

It really needs to be 2 or 3 KVA, ..............so as to minimize restricting dynamics on music peaks.

Just LOOK at that thin cheap-looking power cord. And the flimsy - looking switches.

When you add complex things like this device, especially with a 1 KVA rating, it is only adequate for lower to mid fi audio systems.

THINK of all the ADDED wiring, added switches, plug connections and interfaces you are trying to send the power through !!!!!!!

In the end, " Less ( done properly ) is more. "

KISS ( done well ) often rules............... IMHO.

Again, I am not trying to pick an argument.

Respectfully a second time, You are calling this device a " voltage stabilizer". Are you sure this is what is is and does? Might it just be a One KVA Isolation Transformer, in which case, voltage fluctuations get passed right through it, on a one to one basis ???

Jeff

PS :

You are calling this device a " voltage stabilizer".

Are you sure this is what is is and does? Might it just be a One KVA Isolation Transformer, in which case, any voltage fluctuations get passed right through it, on a one to one basis ??? Isolation Transformers are OK, to clean up line noise a bit, but it better be something like a BIG HEAVY ( weighs 56 pounds ) SIGNAL DU-2, which is 2 KVA , to minimize loss of dynamics.

 

[Kannan]

Respectfully, IMHO / IME ,

1 KVA is certainly a degrade VS plugging any amp ( I would use ) directly into the wall !!

It really needs to be 2 or 3 KVA, ..............so as to minimize restricting dynamics on music peaks.

Just LOOK at that thin cheap-looking power cord. And the flimsy - looking switches.

When you add complex things like this device, especially with a 1 KVA rating, it is only adequate for lower to mid fi audio systems.

THINK of all the ADDED wiring, added switches, plug connections and interfaces you are trying to send the power through !!!!!!!

In the end, " Less ( done properly ) is more. "

KISS ( done well ) often rules............... IMHO.

Again, I am not trying to pick an argument.

Respectfully a second time,

Jeff

you are jumping to conclusion as usual. Did you check with me what is the total load of my audio system? 1KVA is more than sufficient for my need.
Though I do not use this one, I use an isolation transformer which is 1KVA and I have no issues.

Anyhow sorry for this divergence from your thread, you may best ignore to reply as then the focus will shift from the build

 

[Kannan]

What you post is not so !!! Expensive baloney. You are often defeatist, negative IMHO. No insult meant.

You are wasting your time, money, and life ................... in middle-fidelity DIY audio.

Yes, you are really wasting your time, money and life...... from my perspective.

@Nikhil @captrajesh @arj Dear Moderators, this is absolute blasphemy of a very senior member @yogibear of our forum whose contributions have been invaluable. Leaving out senior members, even of any member for that matter. I think this member @drlowmu has been given enough rope and it is time for moderators to intervene.

 

[raghupb]

Or send it over !!!

On a serious note can consider a 1KW voltage stabilizer which outputs 230 volts.

I keep building amps, overkill transformers are way expensive for every build.

I personally prefer no voltage stabilizers or power conditioner… Currently settled with 240 voltage primary taps and Torroidals instead of EI core. Would some day experiment with low DCR multiple choke filtered power supply and experience the results myself.

Getting parts in India is a pain and importing is so expensive….

I acquired a 2KVA servo from Vertex about 18 months ago. More than enough for my limited components and usage.
Input variation handled is 170-280V, IIRC. Output can be programmed as per your requirement.
Cost wise it should be about 20K thereabout (not much difference between 1/2/3 KVA). You may want to explore this option.
Yes it is a bit noisy when the servo kicks in, but it can be placed outside the listening area if needed.
Also, they can customize the number of outlets, type etc.

Cheers,
Raghu

 

[RtoR King]

Yogibear,

Thus high VAC line came about the past 20 Months or so in India, as COVID shut down businesses, and the lower overall electricity use raised the VACs at the wall, considerably. Hari was reporting this to me all last year, with his mono blocks.

It is a very poor idea for end-users to be switching Mains Voltage Taps, and adding complexity, un needed, to your DIY build IMHO. Simply " Design center " your amps to take such VAC swings into account !!!

No user adjustments in an amplifier is the superior way to design any amplifier, IMHO !! I do this always.

You need to change your way of selecting and specifying transformers.

The best Power Transformers will have the lowest DCR and be WAY overbuilt, to obtain a combination of reliability, and superior sound.

When WE had SHILCHAR build Hari Iyer's R-Core power transformers in 2020, we needed to power two mono amps with about a 80 mA. total load, for each amp. With me specifying Direct Coupling, we needed about an 800 VCT power transformer. What is that ? 64 VA per mono block I suppose. ( 0.080 A. times 800 VCT )

We specified for Shilchar to START with a 320 VA sized R-core, to do their winding.

Hari had it speced as 800 VCT at 400 mA. or maybe even 450 mA. as I recall. Having a 400 mA. Power transformer doing 80 mA. continuous, is a breeze !!

It is five times over speced. ' Never gets very warm. R cores have a low radiated field also. This conservative spec results very beneficially in low DCR across the entire High Voltage winding ( 70 Ohms as I recall , end to end - please measure and report yours !! ). Each unit runs cool and loafs.

Recall my State of Missouri / USA car license plate ( personalized ) ?? ....................... It is ............." LOW DCR ".

The audio amplifier starts with the power supply, and the power supply starts with the power transformer. Intelligently select it. I saved a personal letter , written to me in about 1989, from the Dean of the College of Electrical Engineering, at the University of South Carolina, USA, about Power supplies. use it as your theoretical guide in amp building !! Dr. Charles A. Halijak . The letter to me is entitled " The Figure of Merit in a Power Supply " :



1989


Dear Jeffrey,

This letter is concerned with the power supply and the use of chokes.

A choke must have some internal resistance and its non-standard figure of merit is the ratio R over L. The best choke is the one with the smallest figure of merit and the best power supply has the least series resistance. It is not too difficult to obtain R over L = 10 but one can easily obtain R over L = 30 or more. The latter should be avoided but the ongoing shows that in a way it is unavoidable.


The choke input filter controls the diode by timing and not by ohmic losses. ( jm: current vs: voltage waveforms) The best place for a choke is at the input and the worst place is at the other end of a power supply filter chain because resistances tend to be higher there.

Suppose we start with your case and R over L = 10. When diode ( 5U4GB) and transformer resistances are taken into account we have :


15 ( choke ) + 70 ( rectifier ) + 70 ( power transformer resistances )
------------------------------------------------------------------- = 103
1.5 ( HY )


( the 70 ohm power transformer resistance is a guess )


If four 5U4GB are placed in parallel one has :


15 + (0.25 ) ( 70 ) + 70
__________________ = 68
1.5


Both figures of merit are way above the original 10 but your listening experiment told you that 68 was alright; this actual figure of merit is the best you can do because the largest power transformer was used and the smallest resistance available choke was used. You can see that stock power supplies are not anywhere near being the best cases.

* Most tube and transistor electronic engineers are unconscious about power supplies, but good.


* Also the best cases need not have zero internal resistance - a utopian goal. One strives for minimal non-zero resistance !!

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

Jeff here :

I want to emphatically point out, that E.E. Dean Halijak's next to last sentence right above ( the first one stared ) are his words in 1989, unsolicited, .....and NOT mine ( in light of my recent promise to this Forum .)

A highly unusual comment ......... coming from the Dean of E.E .

Well, now you all have one clue as to why Dennis Fraker and I uniquely use choke input filters, with two SIX Ohm DC Resistance chokes, and enjoy the hell out of the sonic results. No one else does this.

LOW DCR is ALL part of this thread, very clearly disclosed by me on Page One. Recall ??? When I switched from two ten Ohm power supply chokes to two SIX Ohm chokes, as the ten Ohm chokes didn't cut the mustard.

New Design, SE 6005 Directly Coupled Audio Amplifier

This is a current design and build project, a DIY hobby of mine for many years. It uses a 6005 FINALS tube, which has a 10 Watt (correction - 12 Watt) plate dissipation, and was introduced in the 1950s. Used in car radios and TVs as the FINAL stage, in the USA and in Russia ( an equivalent )...

www.hifivision.com

Fun, huh ? !! I hope some people are starting to see the light, and learn what is important .

As a minimum Yogibear, I would recommend using a Power Transformer at no more than half of it's VA rating. But you can see, Hari 's is operating at 20%, one fifth, as per my influence.

Jeff

What does any of this have to do with the high AC line voltage problem being discussed?

Putting in an oversized power transformer is not the solution. While the primary side of a larger transformer may be able to take the line overvoltage, you still have the problem of B+ being too high. Building a stiff low DCR power supply, while normally a good thing, makes the problem at hand even worse.

The line voltage problem needs to be directly addressed. That can be as crude as a variac and a voltmeter to a high end double conversion UPS unit.

The stabilizing or ferro-resonate transformers being discussed are a good middle ground solution provided they don't have excessive AC waveform distortion. There are units made with reasonably clean sine wave output. And these can be found at good prices on EBAY as well as electronics surplus shops.

I also find it quite amusing that in many posts you denigrate EE's and other trained professionals. Yet when it suits your agenda, you get all behind some EE expert nobody ever heard of. It's also interesting that all the professional references you cite seem to be deceased. To bad we can't hear their ideas from the horses mouth. If these people had peer reviewed published papers I might be more inclined to believe what you state is what they said. I am certainly not accusing you of fabricating stories but we all know a lot can get lost in translation and time. Some of your references have been gone for over 30 years and longer.

 

[raghupb]

I feel this is excellent advice you have given me, and will apply the same, onwards. Thank you, Raghu !

Thank you Sir.

In this journey, I have found, it is not always about the perfect sound reproduction.
It is the experience of epiphany when one listens to a good piece of music/song.
No matter how good or badly it is recorded or rendered, our senses (hearing) forgives it as long as it appeals to the brain.

PS:
This does not deter you from achieving perfection in playback.
It is just that our our ear/brain mapping is very forgiving to "good" music.

PPS:
Listen to this just for kicks and grins

Yes. It is a YT video (definitely questionable audio).
But the ensemble can produce "rapture" at least to me and a few others.
Isn't this what audio is all about?

Regards,
Raghu

 

[RtoR King]

Thank you Sir.

In this journey, I have found, it is not always about the perfect sound reproduction.
It is the experience of epiphany when one listens to a good piece of music/song.
No matter how good or badly it is recorded or rendered, our senses (hearing) forgives it as long as it appeals to the brain.

PS:
This does not deter you from achieving perfection in playback.
It is just that our our ear/brain mapping is very forgiving to "good" music.

Regards,
Raghu

More excellent advice Raghupb!

There is no such thing as perfect sound reproduction by electronics means.

There is no perfect amplifier.

There is no best amplifier. And if there was it would earn that title by virtue of electronic measurements. That's the only thing that is reliable and cannot be disputed provided the test gear is accurate. Listening tests are always biased. No way around that. That's not saying the best measuring amplifier is the best sounding. It may be to some and not others. And engineers are hardly exempt from placebo effect either. If one measured a near perfect amplifier and believes in measurements, that amplifier will sound great to them to spite having some unmeasured sonic flaw. I know! I've been there!

So enough of the "I built the world's best amplifier"! First, there is no proof of that, not even an honest attempt. And to even try and prove that is hopelessly impossible. Just report what you hear. And even if you want to apply electronic voodoo to reason it out, that's OK too. It's just one's opinion based on their understanding of electronic principles. But stop this inference that nobody else is smart enough to do the same. I say many others are smart enough NOT to try it.

I gotta tell you, I have seen pictures of Mr. LowMu's speakers. Cabinets are quite beat up. Woofer cones clearly show signs of deep aging, need to be re-coned. Tweeters are supported by rolls of tape and golf balls. The crossover is built on a board and exposed. The tweeters have been hacked so that the wire terminals have been removed and the crossover direct wired to the voice coil, how, we can't see.

So this is how the "best" audio system in the world looks? Once again placebo effect rules. Most people looking at that will be biased against hearing high quality sound no matter how good it may be.

 

[raghupb]

@RtoR King
Most of my music exploration happens on bad YT videos. Why?
It is the most diverse medium today, bereft of paid subscription services.
I listen to a "wide" variety of music, yes in quotes. Because, my wife has wider variety, who am I to argue.

In 35+ years in this hobby ...
Thanks to my dad who introduced me to music, Indian, Beatles and Osibisa
... it is not the sound of music, but the content.

But, I definitely respect the purists who pursue the art of reproduction.
They should be respected for what they do and can deliver (maybe) for us mere mortals to enjoy.

Cheers,
Raghu

 

[RtoR King]

Here's a link based on my prior post.

High Efficiency Speaker Asylum

Audio Asylum - High Efficiency Speaker Asylum - Need speakers that can rock with just one watt? You found da place.

www.audioasylum.com

 

[raghupb]

@drlowmu
A good example of agree to disagree.
In India we two main forms of music, Carnatic and Hindustani.
Kinda divide, but not really!!

But listen to this:

Two Maestroes going at it and having fun

Cheers,
Raghu

 

[Dr.Gary]

Here's a link based on my prior post.

High Efficiency Speaker Asylum

Audio Asylum - High Efficiency Speaker Asylum - Need speakers that can rock with just one watt? You found da place.

www.audioasylum.com

While it's ok for the basement or garage, it's not something that a woman would put up with in her living room.

 

[RtoR King]

While it's ok for the basement or garage, it's not something that a woman would put up with in her living room.

Agreed, My point was presentation.

Bring any amp over for an A-B, I would welcome that. ( Any F2A amplifier, etc., ever made, by anyone ) I would love to witness the expressions on someone's face. I have spent my adult life, figuring out what matters in audio performance, and how to obtain it !! Hearing is believing.

I just don't see that happening with the current cosmetic impression of the system. Since we are predicting human perception here, other normal biases must also be factored in.

 

[Dr.Gary]

Agreed, My point was presentation.


I just don't see that happening with the current cosmetic impression of the system. Since we are predicting human perception here, other normal biases must also be factored in.

The A-B test that I'd like to see conducted is a double-blind assessment of those paralleled capacitors agianst a high-quality single having the same equivalent total. In fact, I[d even be willing to bet some money on the outcome.

Agreed, My point was presentation.


I just don't see that happening with the current cosmetic impression of the system. Since we are predicting human perception here, other normal biases must also be factored in.

Agreed. One's natural, initial reaction would be that it can't possibly sound as bad as it looks.

 

[drlowmu]

01-27-2022 Photo Progress Report ....... Above - Chassis ( Finals Rk Bypass ) GTO Mounting DETERMINED ....






Read the background and most recent history of this, click here below :

New Design, SE 6005 Directly Coupled Audio Amplifier

His Post #221. From Gary : " No suppositions. No hypotheses. Just facts that are documented and supported by nearly a century of accumulated knowledge in science, mathematics, physics and engineering. That said, you may well have the best sounding and most accurate amplifier in existence on...

www.hifivision.com

 

[Dr.Gary]

In the post to which you

01-27-2022 Photo Progress Report ....... Above - Chassis ( Finals Rk Bypass ) GTO Mounting DETERMINED ....


View attachment 66658View attachment 66659View attachment 66660View attachment 66661View attachment 66662



Read the background and most recent history of this, click here below :

New Design, SE 6005 Directly Coupled Audio Amplifier

His Post #221. From Gary : " No suppositions. No hypotheses. Just facts that are documented and supported by nearly a century of accumulated knowledge in science, mathematics, physics and engineering. That said, you may well have the best sounding and most accurate amplifier in existence on...

www.hifivision.com

In the post to which you refer, you asked the question "Am I arrogant?? I don't think so. This is my unique audio discovery. " Well, now, since you asked, my answer is that you are not just arrogant, you are a pompous braggart. That said, I will now wait for one or more of the moderators to slap my hand or delete my reply (or both) for giving you an honest answer to a question that YOU explicitly asked.

 

[Dr.Gary]

In the post to which you

In the post to which you refer, you asked the question "Am I arrogant?? I don't think so. This is my unique audio discovery. " Well, now, since you asked, my answer is that you are not just arrogant, you are a pompous braggart. That said, I will now wait for one or more of the moderators to slap my hand or delete my reply (or both) for giving you an honest answer to a question that YOU explicitly asked.

My moral values are such that I would never post a comment about someone who had been banned and who was unable to respond.
For this reason, I asked the moderators to remove my last post in the event that it may have unknowingly and unintentionally been made after drlowmu had been banned.
Given that my last post has not been deleted, that reflects entirely the assessment of the situation by and the decision of the moderators,

 

[mbhangui]

@drlowmu
A good example of agree to disagree.
In India we two main forms of music, Carnatic and Hindustani.
Kinda divide, but not really!!

But listen to this:

Two Maestroes going at it and having fun

Cheers,
Raghu

This was more like a blend of Hindustani Classical and Carnatic. The blend was so perfect that I couldn't figure if this was a Hindustani or Carnatic, two totally different forms for classical music. I guess they must have practiced it well before the live performance. The Mridangam and 18th centure Tabla blended so well together.

BTW. The combination of two inhomogeneous circular membranes allows for the production of unique and distinct harmonics. Pioneering work on the mathematics of these harmonics was done by Nobel Prize-winning physicist C. V. Raman. The Mridangam origin is more than 2000 years old. https://www.ipassio.com/wiki/musical-instruments/percussion/mridangam

 

[sunilj]

Is there a 'Season 2' to this soap ?

 

[sunilj]

I was surprised drlowmu (Jeff Medwin) was allowed to continue for so long. He's had some hilarious and legendary head on with industry folk. He's been banned /reinstated from audiokarma, hifihaven, hostboard and audioasylum that I know off.

So imagine my surprise when his head pops up on our side of the globe.

 

[drlowmu]

I was surprised drlowmu (Jeff Medwin) was allowed to continue for so long. He's had some hilarious and legendary head on with industry folk. He's been banned /reinstated from audiokarma, hifihaven, hostboard and audioasylum that I know off.

So imagine my surprise when his head pops up on our side of the globe.

Hello Sunilj,

Very nice to meet you. I have been on HFV for sixteen months.

I discovered this Forum after Hari Iyer introduced himself to me. He requested some guidance with a S.E. D.C. tube amplifier design. This HFV Membership offered a fresh new opportunity, to post about my own DIY audio hobby, wherein I am mostly concerned with tube amplifier design.

I was appreciative of being given a fresh clean start on HFV, and tried to post positive contributions, based on my direct findings and unique experiences.

My earned HFV " Reaction Score " to date, is 523.

Of the 523 reactions, there are 505 LIKES, 4 LOVES, 14 HA HAS, and ........ only 1 ANGRY.

There was never a problem for me here, until two new Members joined. It seems that their goal was to specifically post to give me " push back."

I have made two gross mistakes on HFV .................at least.that I can think of :

FIRST : I engaged both of those two USA " trollers " , ( as perhaps they hoped I would ), rather than totally ignoring them.

What ensued was a very sad-to-me... a calamity.

SECOND : I wrote a HFV post to Yogibear, where I severely criticized and publicly belittled him.

In retrospect, this was not the correct venue, to have that discussion. I should have expressed myself PRIVATELY to Yogibear, and I had two ways of doing so. A big mistake on my part.... that I regret. We as humans make mistakes....... sometimes.

Upon thinking this over, I have since written to Yogibear privately, and have told him " I was sorry " for doing that in a public manner, and asked for his forgiveness.

I certainly will continue with my " somewhat-unique " audio work, and hope to contribute here on a upbeat and positive basis, into the future ! The Moderators were very fair to me, and it was appreciated.

I have two new, seemingly worthwhile DIY design and build projects " in mind " for 2022 :

(1) a lovely DCed 12AX7 tube type passively EQed PHONO stage, and optional- use line stage, for analogue fans

(2) and a new " triple " 6005 tube ( SE Parallel, DC ) amplifier , in a monoblock format, ........maybe 9 Watts.

Thanks ........for everyone's most kind understanding .

Jeff Medwin