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In Reply to: RE: I just have to point out one more thing posted by Tre' on December 16, 2014 at 10:52:59
Hi TRE.Merry Christmas to you and yours if I don't get back on here before that.
I decided to do a little Christmas shopping/dreaming, visit a few amps that I like to listen to-- see how their gain structures turned out.
Here's a sweet little 100-watter that I thought a lot of at RMAF-- DarTZeel NHB-108 model one-- Looks like it has 100 watts @ 8 ohms, 26 db gain.
Boulder amps turn me on-- here's the model 1050-- 500 watts @ 8 ohms, 26 db gain. Then, Boulder has the model 1060, that one is 300 watts @ 8 ohms, the same 26 db gain........ OK....
There's Nelson Pass (Labs). The XS 150 is 150 watts @ 8 ohms, 26 db gain. The XS 300-- 300 watts @ 8 ohms is still 26 db gain.
Bryston has the 2.5BSST2-- 135 watts @ 8 ohms. You can choose 23 or 29 db gain-- dealer's choice. Bryston's 14BSST-PRO has 600 watts @ 8 ohms. Again, 23 or 29 db. You choose....
Spectral's DMA-360 and 400 have 300 watts and 350 watts respectively @ 8 ohms, they say 1.5 volts in, and output is "nominal". I suspect they don't get into DB Wars.....
McIntosh weighs in at 600 watts @ 8 ohms with their MC601. It has dynamic headroom of 1.8 db. That's it. Want to argue.... I don't think they would be interested....
MBL says nothing on this subject, neither does AYON-- that I could find. Their big one sounded good driving the big SONY speakers at RMAF.
We all have different reasons for the gain structures in our amps. With me, it's the idea of having a source component that puts out 3 to 7 volts drive right into a passive attenuator into an amp that has 18-20 DB gain structure.
The "Get Better Sound" guy also likes that range-- maybe thinks it's the best. I agree and neither of us coached the other.. We're not trying to run high power amps into high-eff. speakers, or trying to match-up to older gain structure preamps, although the really great ones will work quite well into a 18 db gain amplifier, we just love lively dynamics and great detailing, low interconnect losses---- playing all the musical instruments intact. And simpler amps too!
Merry Christmas, and my best to you.
---Dennis---
.
Edits: 12/16/14 12/16/14 12/16/14Follow Ups:
I also love lively dynamics but gain structure does not affect dynamics unless you're fighting a high amplifier noise floor.
"Bryston's 14BSST-PRO has 600 watts @ 8 ohms. Again, 23 or 29 db"
600 watts [RMS] into 8 ohms is 69 volts [RMS] across the 8 ohms speaker.
If this amp has a gain of 23 the input would have to be 4 volts [RMS] for it to make 600 watts.
Side note, if I needed 600 watts I would have to have a active line stage preamp. My CD player only outputs 2 volts at a digital zero (in other words, it only outputs 2 volts when the digital signal is peaked). If I needed 600 watts, the amplifier would have to produce those 600 watts with only 2 volts input because I will not add a active line stage preamp just like neither of us will add a third stage to our power amps.
"DarTZeel NHB-108 model one-- Looks like it has 100 watts @ 8 ohms, 26 db gain"
At a gain of 26 this amp requires only 1.4 volts [RMS] input to make 100 watts.
None of the amplifiers you listed follow your rule and nothing about the gain of an amplifier will affect the dynamics so I still don't understand what you rule is about.
"With me, it's the idea of having a source component that puts out 3 to 7 volts drive right into a passive attenuator into an amp that has 18-20 DB gain structure."
What source component output 7 volts? Active line stage preamps? You do understand that it doesn't matter if the extra stage is in the preamp or the power amp. An extra stage is an extra stage and I thought you were against that?
I run my CD player (2 volts RMS at max) and my phono preamp (perhaps a tiny bit hotter) into an AVC and, with very little gain in my amplifier, I can play my system louder than I ever want to.
I would think the same would be true for you with the very sensitive speakers that you have.
I have no idea what you do with all the gain (19db) your power amplifiers have. I can only guess that you keep your passive VC preamp turned way down.
6db vs. 19db....that would be more than 6 clicks on my AVC switch. I usually run my volume switch at 8 clicks (16db) down from wide open.
With your amp I would have to run the AVC switch 14 clicks (28db) down from wide open. And that would be the difference, not a difference in dynamics.
The bottom line, there is no rule.
If a listener's source outputs enough signal voltage to drive his amplifier to the wattage that is needed for his speakers to reach the SPL at the listening position that he desires, then that's the right gain structure for that listener.
And none of this has anything to do with dynamics.
Merry Christmas!
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
One more time, then-- Hey! It's Christmas!
-None of the amplifiers listed follow your rule- TRUE! They have their own priorities and reasons-- mine work better.
-What source component outputs 7 volts?- The LYNX L-22 computer sound card puts out 3.5/3.5 or 7 volts balanced. Most Blu-Ray players output in this range also. This is absolutely ideal for a passive volume control/attenuator. Blu_Ray movies are now the best sound the consumer can easily buy.
-I can only guess that you have your passive VC preamp turned way down-- It normally runs at 1 to 1:30 O'clock.
-none of this has anything to do with dynamics- Oh, but it does, and the difference is large. You're dealing primarily with the S/N (signal-to-noise-ratio) of the interconnects used in the system.. Any wire has a "perfect" power range where it performs best. Put too much energy into it, and it balks, put too little in and it becomes a poor conductor at that signal level.
This does depend on what interconnects are used, how good RCA jacks are, etc., but in general, the boutique wire makers have this pretty well ball-parked for their intended uses.
If you build your own cables & interconnects, (I sometimes do, and sometimes I buy them-- depends), then you'll want to take a look into that.
---Dennis---
The LYNX L-22 computer sound card balanced output is pro +4.
That's a different conversation.
BTW I didn't know your passive VC was balanced in and out?
I know, as a fact, that your power amp does not have a balanced input. So why would you be using the balanced output of your sound card?
The blu-ray players I looked up have 2 volts outputs but there is no standard, no rule.
"We've found some BD players output at 2Vrms when presented a 0dBFS signal while other outputs are at 1Vrms."
You said,
"You're dealing primarily with the S/N (signal-to-noise-ratio) of the interconnects used in the system.. Any wire has a "perfect" power range where it performs best. Put too much energy into it, and it balks, put too little in and it becomes a poor conductor at that signal level."
S/N (signal-to-noise-ratio) of the interconnects used in the system? Really Dennis?
Too much and the wire heats up and the DCR goes up and it becomes a poor conductor.
I guess you can call that "balks" if you want to but 2 volts or 7 volts or 20 volts into the input impedance of the power amp is not enough current to heat up the wire. So once again you are wrong Dennis.
As for "too little in and it becomes a poor conductor", that is just so ridicules I won't even offer a retort.
These things are all just more of your made up stuff Dennis with no basis in reality.
You can have an opinion but when you state your opinion as fact, without showing technical proof, then you and I will have a problem.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
"Oh, but it does, and the difference is large. You're dealing primarily with the S/N (signal-to-noise-ratio) of the interconnects used in the system.. Any wire has a "perfect" power range where it performs best. Put too much energy into it, and it balks, put too little in and it becomes a poor conductor at that signal level."How does a passive wire have a signal to noise ratio spec?
You remind me of a "computer tech" years ago who told me I can't make RS232 cables with 22awg wire because "the thicker wire soaks up too much data".
P.S. To the more technical here: Lets not get caught up with all the RF theory that would support the computer tech's theory with high speed data transmission! This was 9600 baud at less than 50 feet! As with audio signals, data signals at that rate and equivalent frequency are not sensitive to these parameters.
And FWEIW, CAT6 cable is 23ga where as CAT5 is 24ga due to the RF issues.
Edits: 12/17/14
The Bryston owner's manual says that with the 29dB setting, 1 volt in produces 100 watts into 8 ohms and with the 23dB setting you need 2 volts in to get 100 watts into 8 ohms. see the link, it's on the last page. They don't indicate the voltage required for 600 watt output.
"They don't indicate the voltage required for 600 watt output. "But they do. The gain of the amplifier is either 23db or 29db and that tells us what we need to know.
Using the 29db setting 1 volt input gives 28 volts across 8 ohms at the output. That's 100 watts.
At the 23db setting 2 volts input gives 28 volts at the output.
At the 23db setting it will take 4.8 volts input to get 69 volts out. 69 volts across 8 ohms is 600 watts.
At the 29db setting it would take 2.4 volts input to get 69 volts output.
Kirchoff's law, power = current times voltage and the online calculator linked below.
What bothered me is that Dennis stated,
"Jamie, the CORRECT gain structure for any modern amp, regardless of whether push/pull or single-ended, regardless of whether 2, 3, or 4-stages-- the CORRECT gain structure for all of these amps is NOW 18-20 DB of amplification.
More or less than this IDEAL FIGURE will result in an INFERIOR amplifier if you intend to work with today's line-level music sources.
The gain structure of a 2-stage S.E., using D.C. coupling, driven by a triode with an amp-factor of 100, driven into a 2A3 or 45, falls within THIS IDEAL 18-to-20 DB range. Changing the amp's overall gain structure to use the amp as a volume control is WRONG."
as if this is some kind of axiom or universal truth.
He later softened that to "We all have different reasons for the gain structures in our amps. With me, it's the idea of having a source component that puts out 3 to 7 volts drive right into a passive attenuator into an amp that has 18-20 DB gain structure."
So I guess he was over-stating his point the first time and realized it.
The bottom line, there is no rule and Dennis knows it.
Dennis just wants his preferences to be seen as the only proper way of doing things.
I think Dennis is a bit of a megalomaniac.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 12/17/14
I agree that there's no rule, that's obvious.What you don't understand is the huge performance gains that result when you idealize any set of parameters-- taking each item, and in turn, idealizing it while considering and idealizing all the other factors that are present and interact with each other.
I do that routinely, you are degrading the attention required and the science involved. Apparently just because you don't like it, or wish to attack the messenger..
Name-calling does nothing to improve the performance of equipment. .
Whether there are rules for the things I describe or not, is---- completely irrelevant to our discussion.
What is relevant and obvious to me is that if ANY amplifier, at ANY power output level is operating in the 18-20 db gain structure range, if all other factors are made whole for that gain structure, and if the system is set up to accommodate an amplifier that has that gain structure, the performance of that system will not need any explanation from me or from you-- it's improved performance will be very obvious.
This factor has proven to me to be so great an improvement in ANY system, that I now try to use amplifiers that have that gain structure exclusively-- when I can-- where the requirements are for the best possible performance that one can get from that audio system.
One can build ANY wattage amplifier to the 18-20 db gain structure if he so chooses to do so, and successfully set up an audio system to use that structure to sonic advantage.
We all have to live with things that we can buy-- including amplifiers and source components. What I described is an ideal-- one of many factors involved in getting THE BEST performance. I didn't say you couldn't use something else.
You can use anything you want-- just don't attack every improvement that comes along because it doesn't match up with your preconceived ideas and only the science and herd-mentality notions that YOU know.
ALL Science and ALL rules were-- at one time-- unproven. They were somebody's UNPROVEN ideas that later were proven by superior performance, not by agreement among engineers and scientists at that time.
What you THINK you know CHANGES with time. It ALWAYS changes. You can learn how to use something superior, or you can half-heartedly "try" it, and fail, and then conclude that it is "bogus".
The problem with your approach is what do you do when IT WORKS for others and is, therefore, NOT bogus?
You have two choices: (1) You can THINK and see how and why it works, or (2) you can denounce both the idea and its messenger.
I think that History makes it obvious which approach really gets results.
---Dennis---
Edits: 12/18/14 12/18/14
"One can build ANY wattage amplifier to the 18-20 db gain structure if he so chooses to do so, and successfully set up an audio system to use that structure to sonic advantage."So if a person has a situation where 1000 watts on peaks are needed and he uses an amplifier with 19db of gain, where will he get the 10 volts of input signal needed for that amplifier to produce 1000 watts?
I know of no source components that outputs 10 volts. So now, because of your rule, that person will need an active line stage preamp.
So now it can be said that Dennis clearly states that adding an active line stage preamp is a sonic advantage?
I know you don't believe that.
I think what a person would want is an amplifier with a gain and power rating that gives the power that's needed for the situation using only the output voltage of his source component without the need of additional active stages.
Doesn't that sound like a better rule?
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Edits: 12/18/14 12/18/14
So Dennis,
If you have uncovered and implemented these new techniques which contradict established electronic theory, why is there no documentation of it past this public hobbyist internet forum?
Why have you not published your findings in a technical journal?
Why are these ground breaking techniques you have been practicing since 1989 (per LowMu) only admired by casual hobbyists who lack formal technical training?
Where is the commercial application of your techniques beyond your own niche product offerings?
To my knowledge you have no patents or copyrights filed so anyone is free to copy your work for commercial gain is they choose.
Why has no one done that?
Philanthropy
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