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Not to beat it into the ground, but...........
All of us have individual preferences of what is a great audio system. So, individuals should suggest what they prefer vs telling others they have a less than stellar audio system compared to their audio system. We all hear a little differently as well adding more variance to the subject.
On that basis alone, no one is the ultimate authority nor would be able to achieve an unanimous consensus of the best audio ever from a certain design.
AA is absolutely invaluable with all the info posted over the years. Personally, I would never have the time to experiment even if I never did anything else day & night let alone afford to purchase all the different high quality components suggested here at AA.
Thanks to many here I have achieved my audio goals.
Follow Ups:
Never heard a transformer I couldn't hear although some are pretty good.
If you can get rid of them you are better off.
The next thing to realize is that the topology of the amp/preamp will govern the sound- the component selection may help bring out better qualities, but the topology will govern the sound.
SETs for example are very rich on account of the lower ordered harmonics, but good at low level detail on account of distortion literally vanishes as output power goes to zero. OTOH, they get their 'dynamic' quality from odd ordered harmonics that show up on transients when you push the amp (the human ear uses odd-ordered harmonics to determine how loud the sound is- if they get messed with, the amp/preamp will sound louder than it really is). IOW, its all about distortion. How well the amp manages these aspects is the difference you hear between them.
Feedback adds to odd-ordered harmonics, which is why its reputation is variable.
I prefer an amplifier that is fully differential, as there are no even-orders to make it unnaturally rich, mostly the only harmonic to show up is the 3rd if you don't run feedback. But to run without feedback, you have to do everything you can to keep distortion down: one stage of gain, triode operation, no phase splitter, no output or interstage transformers, etc.
OTLs can be plenty reliable if built correctly. They can be so wide bandwidth and so low distortion (and can offer a lot of power), its hard to go back to anything else, IMO but OTOH I make them so take that for what its worth.
"So, individuals should suggest what they prefer..."I'll take you up on that. Just a personal view of the sound that works for me, which has been worked out over several years through trial and error and the advice and ideas of several creative asylum seekers, looking to cross the frontier to paradise.
Three things transformed my own 300b SET system:
1. Directly heated triodes for ALL tubes, not just outputs. This was a huge step forwards - at last I got all the delicacy, instrumental timbre and transparency I was seeking. Tubes like 10Y, 46, 26, 4P1L are levels above any indirectly heated tubes. Yes, you need them in all the line/input stages, not just the outputs.
2. Filament bias. This all came out of the 26 preamp project, which is a huge thread on DIY Audio called "26 pre amp". It works beautifully for tubes like the 26 and 4P1L (in triode) and has now become the preferred biasing method for the latest generation of 26 preamps. It works great for the 4P1L as a driver stage, and I now use 4P1L as the input tube as well.
3. Transformer coupling all the way through. Expensive, but does away with caps, plate resistors, grid chokes and all the rest. With three stages you need two interstages - I'm using LL1660/18mA and Hammond 126C for the input and driver stages, both 4P1L in filament bias.
I hate bypassed cathode resistors, and am trying to summon up the courage to use filament bias to replace the bypassed 1K resistor on the 300b. That's a bit nuts, if you do the calculations. Something like a 50 ohm cathode resistor at 200 watts. It's not impossible....
I'd just like to end by saying that ALL the advances I ever made were through collaboration. Without the generosity of spirit of fellow builders and forums like this none of it would have been possible. We learn and learn.
Andy
Edits: 08/29/12
It sounds interesting to try. I've only really seen this approach on DHT-SET.
If you've looked into this, or done it, do you have a reference for a schematic that looks like it might be successful? I know the quality of the iron is all-important.
Observe, before you think
Hi Andy,
I am not saying that your amplifier does not sound better with directly heated triodes than it did with the former indirectly heated tubes, but can you offer some physics or at least a hypothesis as to why this is?
Phil
There is no iDht that isn't less linear that sounds better then a dht is there? I think the idea of trying to heat up a insulated cathode cover just doesn't work well either for many reasons, space no current bias on the cathode thats helps with signal transfer. I don't see any voodoo. Its pretty obvious. Dhts are more linear. The transfer signal better then any other device. The smaller ones sound better because of the laws of diminishing returns. IE A 100ma power supply sounds better with a 20ma dht then a 80ma one. And the more voltage and current the more noise. It always a compromise for me. I know a bigger driver is going to sound better but a smaller driver I might get away with Allen Brady instead of mills in the noisy parts cathode plate etc. A bigger trans will have less bandwidth and on and on. Its not going to stop me building a 4e27 SE amp though;) just in case. Even though my 10y amp is making all the power I need atm. Maybe I should just use the 4e27 to drive my 10y.Filament bias it of course.
Seriously though I have never used filament bias because every time I see those ugly yellow metal oxides lined up in Thomas's amps I cool off on the idea of going to all the trouble of doing so. I don't hate caps as much as I hate those yellow resisters.
Not saying I am right just saying I am lasy and poor I guess and thats my justification.
Hello Phil,
No I can't offer any physics, unfortunately. I'm just an ex-pro musician so all I can offer is the viewpoint of somebody for whom sound has been a life experience. I'm personally convinced about what I hear but that's obviously subjective so I'm not making scientific claims.
I wish I could give you an answer - I'm extremely curious. I love science but it isn't my field. No doubt there are some theories about.
The thing about DHT small tubes, however, is that it does allow for filament bias.
Andy
I've thought for a long time that IDHTs with higher power filaments sound better. Maybe the entire issue is one of emmissivity.
--------------------------
Buy Chinese. Bury freedom.
Hi Andy,
I'll think one up now.
With a directly heated tube the cathode is for the most part at the same potential and the voltage gradient between the control grid and the cathode is pretty much the same over the whole surface of the cathode. On the other hand with a directly heated tube there is a voltage gradient across the cathode and therefore a difference in grid cathode voltage depending where on the cathode you are looking. This results in many "micro-tubes" in parallel each with a slightly different bias. The nonlinearities of each "micro-tube" is offset from the others with the result that the aggragate is more linear.
Phil
hmmm... Interesting thought.
how do you envision AC vs DC heating to come into play here? Dc has a fixed gradient where AC has a moving target where at any point in time t can be from 0V to 1.4X Vf.
dave
Hi Dave,
I was thinking DC across the filament. With AC the bias offset of my "microtubes" would be, as you stated, swept at the AC frequency. If the AC is from the mains I would expect some hum. With ultrasonic AC I would guess the dithering effect would be analogous to dithering used in digital audio to linearize DACs.
Phil
The cathode (both direct and indirect) simply produces a cloud of electrons that are boiled off into the vacuum of the tube. The plate attracts these electrons and the grid modulates their flow to the plate.Once an electron is free it can go about anywhere in the tube until it is attracted by the plate. No "microtubes" can be created because there are no boundaries and large space between the elements.
It could just be that a filament is very good at producing the electron cloud, particularly thoriated tungsten, better than the one you get from an indirectly heated cathode.
Edits: 08/29/12
Chris.
Here is a very interesting thing for you to consider.
The Eimac 304TL has two filaments that can be wired in series or parallel.
when wired in parallel, all four sections cherry up at the same time. When wired in series, two will cherry up first then the other two will follow. The simple explanation to this is one pair of tubes is biased 6.3V away from the other causing it to draw more current and cherry up sooner. If you reverse the filament polarity the sections that cherry up switch.
Now here is the fun part. Take a single 75TL and watch how it cherries up.
what does this tell you?
dave
That your 304TL switches when the DC filament supply polarity flips makes sense because these are physically 2 complete vacuum tubes in one envelope with different potentials. The bias is obviously affected.
A single element tube like the 75TL tells me that the cathode does not heat at the same rate over its entire surface. In fact, it is physically impossible for it to do so. Also, the materials are not 99.999999999999% perfect so there is going to be some additional variability.
The emissions from any point on the cathode will be most strongly attracted by the part of the plate with the closest physical proximity. So if point A on the cathode has higher emissions during warm-up or even operation, the corresponding point B on the plate that is closest will have a higher temperature due to increase current. This is why misaligned tubes result in hot spots on the plate.
They sound really good, none the less.
but why does the pattern of the red glow change when you flip polarity?
dave
Let's say you have a 10 amp DC filament that has 5 volts + on one side and zero on the other (assuming that we are talking fixed bias for the example.
If the filament is straightened out it could be 5 inches long.
Take the first inch of the filament where the positive 5 DC volts are applied and measure, the drop will be one volt (5v to 4v) over that first inch. Therefore, the last inch will drop one volt as well (from 1v to 0v).
While both one inch sections will dissipate the same 10 watts, the first one inch section will average 4.5 DC volts above zero and the last one inch section will average 0.5 DC volts above zero.
The effective bias around that first one inch section will be 4 volts different than the effective bias around the last one inch section. This will lead to a different level of current flow based on the direction of the applied DC.
Indirectly heated cathode tubes do not have this condition as the whole cathode is roughly at the same potential.
I don't know, perhaps you could call the sliding bias condition on the plate "multiple little tubes", I would rather think that it is just a feature of directly heated cathodes. I can't really see how it would create a sonic benefit. I guess I have a limited imagination. ;-)
Chris,
you just repeated exactly what I have been saying.
I think it is acceptable to look at it as the "microtube in parallel" model with the average characteristics being the parallel combo of all of the "sections"
bias is only one of the characteristics to consider. Actual element spacig irregularities also cause different characteristics for different parts of a tube.
dave
. Actual element spacig irregularities also cause different characteristics for different parts of a tube.
Yes, that as well.
Phil
Hi Chris,
You don't like my "micro-tube" hypothesis so you come up with one that says that thoriated tungsten emits "nicer" electrons than oxide coated cathodes? Do oxide coated directly heated cathodes also produce "nice" electrons?
Phil
FWIW Andy I have been reading your posts for maybe ten years and have always taken any of your findings as absolute and have never been disappointed in doing so. Admittedly I did so in the beginning because I thought you where the Andy Grove was it? that designed amps for hifi world and audionote all those years ago when I used to buy magazines lmao. But you have never done me wrong anyway so you may as well of been him lmao :)
that is ditto for most of the regs here accept the devil guy that left I suppose. And a few other no-alls that like to bully and treat me in a condescending manner with out even taking the time to find out if they do know it all. And yes those guys usually can quote big maths equations and yet some have very little real world audio system building experience in a holistic sense.
Most the time I usually let them be right even when their so wrong because its pointless arguing and you know they usually are that way because they are impotent or come up really short in some way and need to be right to feel better about themselves. And they are always just waiting to attack you if you even accidentally undermine their infinitely huge but fragile sense of superiority. :_-|
People like that love to run me down because I refuse to engineer every thing endlessly before I pick up a soldering iron. And tend not to take things too seriously. But I think since I am 44 and have been into hifi since I was ten and have been obsessively building all my hifi since my accident in 93 day and night even in my dreams. I think experience counts for something and I deserve a little respect even if I don't spice every resister change.
And If I cant have it you can all go stick it and I will open a Rommy forum and learn to speak my own special code language that you must learn to type or I will insult you and ban you instantly from my forum OK!.
Honestly this forum gets to hard for somebody of my lowly intellect . Thats why Tube builder left. He just got tired of being bullied and belittled by sad insecure Napoleonic types. Is that a word lol I am leaving again. Of course I will be back with a new alias in a few months when I get bored pretending to be normal and capable of being treated respectfully and serious OK! TB:)
And Dr Low mu you are a big self involved bully. Who seems to live not for building amps but for bullying and arguing endlessly on this forum. I sometimes wonder if your not some program that someone wrote for a thesis. Because you are so self involved you don't seem to care about anything or anyone other then your endlessly repetitive low DCR mantra. I think in another life you could of been a good fundamentalist Christian. Its such a shame that you really seem to in-fact know it all and really are right about most everything pertaining to tube amps. I bet you cant do up your shoe laces though. Surely there is no room left in your brain to remember how.
nt
Like another poster said - you have a great sense of humour. Got me laughing. Just the thought of Napoleon and that hat....
"No single ended nonsense for my tonight, Josephine, I'm conquering Prussia tomorrow..."
Andy
has Napoleon wearing a pair of their 'phones, with (presumably) Josephine towering behind him. Simple, to the point slogan:
"Complex Sound"
lol somthing really funny Andy Well I think it was. You cant make a omelet without cracking a few eggs. Goodnight!
Granted, feedback solves many problems.
It also gives you a great "free" place to put in some tone control. Try a 0.47uf bupass cap if your system is sounding a little dark. This can vary from 2.0uf to 0.01uf to change the frequency knee where the feedback gets extinguished.
Hi Chris,
It's like Wagner's Ring Cycle.... everything has consequences!
Andy
Wow! You hit one out of the park this time, Andy!
I will take the time to comment-- maybe even more can be applied here:
(1) DHTs for everything. NO argument whatsoever. Only problem I have is how do you find DHTs with an amp-factor of 100, so you can Direct-Couple a two-stage?. I still think that your approach WILL result in very good fidelity. I'm really splitting hairs here-- well, almost. Two stages tied-together is a great thing! It acts just like ONE TRIODE if all is done right.
(2) Filament bias. Right-on. There is no better way to run a DHT. BUT--IF one buys the best caps, resistors and is VERY CAREFUL-- he can get cathode bias to work. It IS difficult. There are some advantages to it-- the bias provided by the cathode is signal-related, it's not fixed. I think you can get great results either way. The SOUND of each is different when each is optimized. Which do I prefer? EITHER!
(3) Transformer coupling all the way through. Well...... it CAN sound very excellent, BUT-- it does add some signal delay and some rolling-off of both highs and lows like all iron does. How much? How fat is your wallet? The better the iron, the better it gets. NO argument-- however, you have yet to hear really good D.C.-coupling. If you can get to RMAF 2012, do it. We'll have a ball with this discussion if you do. It will prove a great learning for us both.
(4) "hate" bypassed cathode resistors. I did too until I realized that I had to do it VERY right. The parts cost money, that's for sure. But don't hate it. Get the best resistors-- be sure to use two in parallel on the cathode. These must be within 1/100th of a percent of each other, so buy a few. If you don't get this close, you'll have two signals there. If you do, the two paths will make only one sound like a Tin Can (by comparison-- it's not THAT bad!). I suggest perfecting this before jumping off the cathode bias supply cliff.
(5) Truly, I think this forum has really excellent representation, and that includes the people who argue with me. There is real talent here. I would appreciate that argument not be politically motivated. The object is the best sound-- not the glitziest arguments, graphs, charts and proofs!
Thanks, Andy. I like your post-- a lot.
---Dennis---
"IF one buys the best caps, resistors and is VERY CAREFUL-- he can get cathode bias to work. It IS difficult. There are some advantages to it-- the bias provided by the cathode is signal-related, it's not fixed."
Can you please explain how a bypassed cathode resistor causes a signal related bias voltage?
"These [cathode resistors] must be within 1/100th of a percent of each other, so buy a few. If you don't get this close, you'll have two signals there."
If the cathode resistors are bypassed, there is no signal (AC) flowing through them, just DC. The signal (AC) flows through the caps, the DC flows through the resistors. You have two DC paths but (in your case with 6 bypass caps) 6 signal (AC) paths.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
"If the cathode resistors are bypassed, there is no signal (AC) flowing through them, just DC. The signal (AC) flows through the caps, the DC flows through the resistors. You have two DC paths but (in your case with 6 bypass caps) 6 signal (AC) paths."
Agreed, but a far better question is WHY the capacitor {bypass for resistor in cathode bias} used has such a marked influence on sound?
{I use Polycarbonate}
The Mind has No Firewall~ U.S. Army War College.
"I use Polycarbonate...."
I used to use a pot of best Russian caviar bypassed with a dozen snails in garlic, ten frogs legs a la maniere de Borodin, a tub of pate de foie gras, a half dressed photo of Brigitte Bardot and a couple of bottles of vintage Bollinger champagne.
I had to give up in the end - the highs were wonderful but the lows were dreadful.
Not sure what you are saying Andy,
everything is a balancing act, like a Chef with a recipe,
or pushing on a balloon.
There is no magic bullet.
Most people know the order is Teflon, Polystyrene,Polycarbonate, polypropylene, polyester, etch with film tin/aluminum superior to metallized.
The best is no cap, The best is no interconnect {Bill from Audioquest was Right}
So was Theodore Sturgeon
{90 percent of everything is crap}
Everyman aims for his own sparrow, you choose the composition of the arrow within the quiver of your mind.
The Mind has No Firewall~ U.S. Army War College.
Hi Dennis,
Maybe the emphasis should not be about meeting God but avoiding the Devil in all his incarnations.
I don't think we'll ever see the end of discussions about how to bias a tube and how to couple stages together. It's pretty basic and unavoidable.
Compromises all the way. There's no decent DHT with a mu over about 15, and I'd even say 10 generally speaking. So that adds stages, no getting round that. I'm sure there are ingenious solutions like solid state hybrid arrangements and in time they'll come out of the woodwork.
Filament bias is probably the worst system except for all the others - like they say about democracy. It's only practical with a few tubes and requires ultra clean DC supplies and quality wirewound resistors. But given that It works like a charm.
Direct coupling is a no-brainer except for the added design problems that throws up. Back to cathode resistors and bypasses. Not a road I'd ever go down unless I was forced kicking and screaming to do so. I tolerate it in my 300b output but only for want of a better solution.
That's it really - everything we do in the end is because we can't think of a better solution and end up with the least bad compromises.
Maybe we should discuss how to build the "least bad" system rather than the best one. I'm sure that's what we all end up doing in practice.
Andy
"Back to cathode resistors and bypasses. Not a road I'd ever go down unless I was forced kicking and screaming to do so. I tolerate it in my 300b output but only for want of a better solution. "
One word, UltraPath.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
http://db.audioasylum.com/cgi/m.mpl?forum=tubediy&n=11390
Hi Andy,So, specifically from the above post, on your 300B's Rk, use two resistors in parallel, matched to that tight Ohmic tolerance spec Dennis suggests, and tell us what you hear !!!
IT will sound better than one Rk, IF perfectly matched.
You should have a SHORT return path to ground on that Rk, I like two inches or less of wire to a star ground, and USE the resistor leads and body length to comprise part of the distance to ground.
Can this be simulated, well I am not sure. Are Rks in parallel, implemented as described, audibly better ?? :-) OH Yes.
Jeff Medwin
Edits: 08/29/12 08/29/12 08/29/12
What amasses me is people state how methodically they have tested this cable or cap or power supply and how it MUST be or it's JUST not high Fidelity and then you find out they are using some radio shack speaker or something like that. People seem to get stuck in one forum ;) like audio Autism
~!~
The Mind has No Firewall~ U.S. Army War College.
That started my day with a good laugh.
Thanks.
" ... people state how methodically they have tested this cable or cap or power supply and how it MUST be or it's JUST not high Fidelity and then you find out they are using some radio shack speaker or something like that...."
I think that's highly unlikely. This is a forum for discussing tube equipment. Most of us also use other forums for computer audio, speakers etc. I think you'll find that builders who put a lot into their amps reserve at least some of their time and energy for the rest of the system. We don't discuss it on Tube DIY but if you follow the various posters you'll see they are active on other forums.
Good for you Neff! Glad you've reached your audio goals. I don't believe I've gotten there yet, though I am very happy with the system I have now. Its the best sounding to me out of the thirty or so different ones I've had in the past. I'm still on the quest for better sound though finances have taken their toll on me in the past couple years. Gotta thank our present & past politicians for that. 'Change' has not been good to me and that's about all it's left in my pocket.
I don't care what anyone thinks of my system or of all the stupid arguments you find here on this forum from people argueing about things they can't hear. So I'm with you on telling people about what 'you' prefer. I'm sick of all the attacking and defending of one's opinion or of their training. I don't care what your background is or isn't. If you have to attack someone or defend yourself, then you're not all that smart and I'll 'possibly' consider your information with a grain of salt.
Wish I'd reached my audio goals as you have, then I would not have to sift through all the bickering and fingerpointing on this forum to get to the 'God sent' sound I'm looking for. Occasionally the responses are amusing, but it gets really old, really quick, especially lately.
These guys can't even stay on a subject without going into 'attack mode' and they accuse the other guy of hjacking the thread. Sometimes the ones being attacked have not even posted anything and they're getting a dose of DIY Tube 'mob rule'. Of course its okay.....after all they are 'professionals'......maybe they are because of their training, but they're not acting professional according to ethical standards. You don't have to defend truth if you're right. You just state the truth and leave it at that. No argument.
Anyway, congrats Neff! Now you don't have to spend so much time here. This DIY Tube forum is seeming to be heading the way of AudioGon and is becoming much less desireable to frequent due to lack of useful information. Thank God for the archives.
Larry D.
Don't thank pollutions. Fight for what is yours. Own your production.
Despite all the gnashing of teeth on the AA---- you're happy!
Wow!-- I love it!
Keep up the good work. Don't be afraid to try new ideas. Once you hear some of them, you can't go back! Oh, OH! That's another can of------ I'm sure you get it-- it never ends if you continue to pursue it.
BUT-- do think about it. Would you rather listen to what you had 10 years ago-- or what you have now?
---Dennis---
Here's a paragraph right from your own website."People you can trust: Over 20 years, no amplifier ever built by Serious Stereo has failed, had to be updated, or been repaired. You can have absolute confidence in our equipment. We work with you. We can help make your entire sound system a success and a trouble-free one at that."
Seems that your 20 year old product is just fine. All anyone could need.
Surely you're not now saying that customers that bought later years models have a sonic advantage?
Edits: 08/28/12
I just happen to have the first pair ever built. Would you like to hear it?
You can if you come to RMAF 2012-- Room 2020 and request it. We'll just do it for you!
---Dennis---
.
What I had ten years ago IS what I have now ...
...
I'm not sure what that means ...
The preamp that I worked on for over 5 years was - frankly - a disappointment. No, it has nothing to do with the power supply, but everything to do with the choice of tube (46) and the volume control. The gain is too low for this application, and they are far too microphonic. I "cheaped out" and used a Russian military surplus 24 position shorting switch for the volume control. It's reliable and all that, but it's pushing the limit of human strength to turn it. And when you do, the microphonic tubes emit a "ping" from the mechanical noise of the switch that drives me nuts. My wife complains about no labels on the preamp, which IS a valid point. So I'm back to my crappy NAD preamp, with all those electrolytic caps that have deteriorated over the last 10 years.
"We live and die by the choices we make".
By the way, I have yet to find an affordable speaker that sounds as good as my 25 plus year old JBLs (L60T's, I think). Too bad JBL went the way of most of corporate America, and now produce mostly cheap junk in China.
I record an acoustic guitar on a nice reel to reel machine and play it back through my system and if it sounds like I layed it down the system is accurate. and that's all we (should) want.....
Wait, you said not to say that. Thats right.
People don't so much argue about subjective things, but rather the misapplication and misappropriation of scientific facts.
I have never read here where someone has called someone else's system garbage.
"I have never read here where someone has called someone else's system garbage."
My modest system has been called "horrendous" by a forum member whose name I'll refrain from mentioning.
I have been told my system could never sound as good as their system. Not that I care about that statement.
Nothing wrong at all regarding science & engineering, but the argument does come down to what sounds good & especially so when some cannot defend their design from an engineering standpoint.
That is how I read into it.
Gee WHIZ Neff,
I am thinking you are talking about me.
"some cannot defend their design from an engineering standpoint."
IF SO ..................................
I am NOT an EE, and so, I don't have the knowledge to fully explain
what any design does, the hows and whys. I am an audio amateur, a build-and-listen reasonably experienced one.
Now Neff, just think for a moment or two, I very distinctly offered you a EE explanation of the new power supply design, written by two smart and very well regarded Forum members / graduate EEs who DO know how to express themselves in EE terms.
So your above comment is not totally fair, IF you refer to me.
I really DID try, to the best of my ability. Knowing my own limitations, I offered you the two E.E.s' chronological compilations, more than once, and you refused the materials - to read and consider, every time. Correct. ?
My offer remains, to anyone, email address is above.
Jeff Medwin
I'll be the first to say that a design that looks good on paper doesn't always pan out. But the converse is NOT true. If it sucks on paper, it sucks in real life. That's why I (and probably others) didn't take you up on your offer. I get enough junk mail as it is.
--------------------------
Buy Chinese. Bury freedom.
Edits: 08/28/12
What if it looked very good on paper, and sounded great after it was built!----?
---Dennis---
Look here dude,YOU certainly do not know what to measure, AND how it correlates to GOOD sound.
If we do a step test in PSUD 2, how do you think your supplies will hold up? AND, what makes you even think that a PSUD 2 step test is INvalid when looking at Dynamic response? AND, what makes EITHER of us think that simulations alone will "cut the mustard?" In reality, it ALL has to be listened to, not as a breadboard, but, as a finished product.
Measures good, sounds bad, its BAD.
Measures bad, sounds good, its GOOD.
We are not measuring the best things, we THINK we know how, but we
are fooling ourselves, and inadvertently, being dishonest .The ear, and a sense of honesty, is vital, the final arbitrator.
Ask yourself : how does it sound compared to live unamplified music?
When was the last time we heard such music as a reference.
(Where is this in RDH-4??,,, :-) !!)
YOU use chokes to your 211 SE Finals that are 145 Ohms in DCR. You use TWO cathode followers in a SE amp. You also use THREE cap couples in your 211 SE circuit. All these things are known to be compromises.
I could be a bit off, I am writing from memory, of your posted circuit.
Maybe it sounds glorious on your speaker load. I'd love to A-B it on High Efficiency speakers.
I personally think YOU have NO room to talk.
Cheers,
Jeff Medwin
Edits: 08/28/12
"When was the last time we heard such music as a reference."
I play piano, organ and guitar. You're an idiot.
--------------------------
Buy Chinese. Bury freedom.
For 15 years as a recording engineer I heard live unamplified instruments every working day.
I studied their sound. It was my job (in most cases) to capture that sound.
As a tracking engineer my philosophy was to record, as full and accurate as possible, the sound of the instrument as to not limit the mix.
This wasn't always the case depending on who was producing. A lot of producers want each track to be laid down the way (or close to the way) he wants that instrument to sound in the mix.
This is very limiting, one can get "backed into a corner" doing things this way. But the best producers can "see" into the future of a session and this method works for them.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
A recording engineer! Still working in that field?
Asa listener, I can say that there are very discernable differences in the way "modern" music is recorded that "old". Which is not to say that everything "new" is bad or everything "old is good. There are exceptions both ways.
Some of the best recordings I have are reltively "old" ones. The "Growing Up in Hollywood Town" (Amanda McBroom) on the Sheffield Lab label and "Midnight at Cabell Hall" (Freyda and the Accustic Attatude) on the Red House Records label are the best. So too is a really old LP "Belafonte at Carnegie Hall" on the RCA label. These recordings are incredibly clear and "precise", unlike some newer CDs, where the audio is compressed to the point of distraction. The worst that I've heard so far is the musical "Wicked". Why oh why oh why do "they" do that?
I'm semi-retired.
Some of the worst sounding recording ever made sound that way 100% on purpose.
Every producer has his own idea of what the public will like. Natural sound is not high on the list these days.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
I'll be the first to say that a design that looks good on paper doesn't always pan out. But the converse is NOT true. If it sucks on paper, it sucks in real life.
who is the great arbitrator of "suckage"?
a real engineer would have the data to back up such a statement.
dave
Dave.... a few days ago you critiqued TK for his questioning your use of subjective terms to describe an audio experience by stating;"Why don't they? they are subjective terms to explain what I hear. People only delude themselves when they buy into the use of objective terms to justify their opinions."
yet the sentiment that you offered just a few days ago seems to be 180 degrees out of phase with your current rejoinder to TK's opinion about a design "sucking" wherein you appear to disallow TK's use of a subjective term and, instead, ask him to provide some "objective" basis for his stated opinion.
Which position is it that you wamt to advocate?
Builder of MagneQuest & Peerless transformers since 1989
Edits: 08/28/12
I was informed that is was not acceptable to use subjective terms. Then the very person who informed me of this uses the highly scientific word "sucks" which I can only assume is his opinion unless he can back it up with some sort of proof.
it doesn't matter how many facts you throw at an opinion, at the end of the day it just comes down to a matter of taste.
dave
I didn't see the "tongue in cheek" and contrasting your two sets of statements appeared to me to be inconsistent. Thanks for the clarification.
MSL
Builder of MagneQuest & Peerless transformers since 1989
It wasn't tongue in cheek, Mikey. He's just being an ass again. Hope that isn't too subjective for you to know what I mean. :)
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Buy Chinese. Bury freedom.
Edits: 08/29/12
And what science have you got to back that up?
You are up late !!
Are you getting your proper share of sleep ??? You need to do that !!!
Jeff
You are assuming a real engineer knows WHAT to measure, and, how much it correlates with the sound.That doesn't necessarily follow at all Dave!!
Some of the NON engineers, your friends, build decent stuff, Hi-Fi Heroin, Dowdy, Josh.
Jeff Medwin
Edits: 08/28/12
Earlier in this same thread, you just stated: "I very distinctly offered you a EE explanation of the new power supply design, written by two smart and very well regarded Forum members / graduate EEs who DO know how to express themselves in EE terms"
Now you are saying that an EE doesn't necessarily know what sounds good.
So, which is it?
JD
"You are assuming a real engineer knows WHAT to measure..."
No one is assuming anything. If even one of the criteria required of a power supply or amplifier can be demonstrated to be deficient, the audio performance will also be deficient. That's why we do mathematical simulations and make measurements. Our ears are the final test, not the first and only. That's how competent engineers design quality equipment.
"Some of the NON engineers, your friends, build decent stuff, Hi-Fi Heroin, Dowdy, Josh"
Of course, and they use the established principles laid down by those who have the technical understanding and honest motivation to create them.
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Buy Chinese. Bury freedom.
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