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Watts aren’t all equal. How to measure an Amplifier’s “Grunt”?

DimitryZ said:
Keep enjoying you great amp! I would probably have Manley or VTL if i stayed with tubes.

I am an engineer, but a "wrong" kind (aerospace, not electrical), so i was consistently belittled and rediculed in previous threads.

Perhaps one could consider this a life lesson - after all we JUST interact with these folks virtually. A blessing, really.
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I don't think anyone was ridiculed or belittled Dimitry ... Many on forums do seem to forget that hi fi IS engineering. Electronic, mechanical, acoustical and sometimes optical engineering and the pure science behind them is what gives us the wherewithal to create hi fi equipment. Without some knowledge of the science behind hi fi it is really not possible to discuss it any detail beyond "I quite like this system/speakers/amplifier".

As an aerospace engineer what would you think of people who didn't know a dihedral from an airfoil section trying to discuss which plane is most airworthy?
 
Darren,

darrenyeats said:
However, Werner's post on page 1 has an explanation of why the valve amp would sound different (for you better) that has nothing to do with soft clipping or level.
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Indeed, and quoted again below since it's now a bazillion posts away.


Werner said:
The high output impedance of the valve amp reacts with the speaker impedance's resonance to create a bass peak. Unless this is intentional it is a form of distortion. Nothing to do with grunt.
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That's very likely what I'm hearing with the GRFs and Stingray — an intentional bass lift — because they really sounded endemic with a Naim 250.

My speakers have early Monitor Reds, which date to 1957 or 1958. I've read that early Monitor Reds, the ones with the orange dust caps, are basically the same as late Monitor Silvers. That means these drivers were designed and manufactured before solid state amps were available. And it's likely fair to say that Guy F. Fountain — Mr. GRF himself — was not designing his DC drivers to work with a kind of amp that hadn't been invented yet.

Joe
 
Joe P said:
Matt,

Cheers, I’m not stressing about it. I’m a rather chill dude most of the time.

I was more confused how anyone could think I was pushing the Stingray to its limits given my speakers and typical listening levels.

If I had Royd Sorcerers and an original Nait I could see the possibility easily, but GRFs with a Stingray...

Joe
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FWIW I have much less "grunt" on hand than you and with speakers far less sensitive (86db, 10ohm) and still don't feel the need for a Gigawatt amplifier.
 
Arkless Electronics said:
I don't think anyone was ridiculed or belittled Dimitry ... Many on forums do seem to forget that hi fi IS engineering. Electronic, mechanical, acoustical and sometimes optical engineering and the pure science behind them is what gives us the wherewithal to create hi fi equipment. Without some knowledge of the science behind hi fi it is really not possible to discuss it any detail beyond "I quite like this system/speakers/amplifier".

As an aerospace engineer what would you think of people who didn't know a dihedral from an airfoil section trying to discuss which plane is most airworthy?
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Outside of professional interactions, it is perfectly fine to have a discussion with "outsiders" who know nothing about your field. What is quite boorish us to use non-proffessional forum for pseudo-proffessional self-affirmation.

Proffessional who is comfortable with his/her level of accomplishment and knowledge doesnt need to ridicule anyone.
 
Joe P said:
Darren,


Indeed, and quoted again below since it's now a bazillion posts away.




That's very likely what I'm hearing with the GRFs and Stingray — an intentional bass lift — because they really sounded endemic with a Naim 250.

My speakers have early Monitor Reds, which date to 1957 or 1958. I've read that early Monitor Reds, the ones with the orange dust caps, are basically the same as late Monitor Silvers. That means these drivers were designed and manufactured before solid state amps were available. And it's likely fair to say that Guy F. Fountain — Mr. GRF himself — was not designing his DC drivers to work with a kind of amp that hadn't been invented yet.

Joe
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They sounded endemic yeah? :D
 
Joe P said:
Cheers, Dimitry.

I have a lot of respect for scientists and engineers. I am neither, but I have worked with them for the past two decades. (If anyone spends ten minutes in the off-topic room they would know I’m clearly a believer in science and what it coupled with engineering can achieve.)

I have to say this thread is weird. I provided a bit of evidence — imperfect as it was — that I don’t listen at loud levels on speakers known to be *very* efficient. I even cranked up the system to stupidly loud levels, and it could have gone louder still, to take another measurement to show that the system can do trouser flapping if necessary.

After all this some are still wondering if my Stingray is being pushed at the levels I *typically* listen at. I don’t know what to say other than that seems very unlikely.

Joe
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So far as I can see, no-one is either 'ostrasizing' you or saying you *are* 'wrong' about the levels you use. All that has been said in that direction is that the peaks may be bigger than you realise from your meter readings, and that the behaviour of valve amp output transformers tends to mean these peaks into real speakers when playing real music have the potential to cause alterations to arise at much lower levels than you'd expect from seeing plots of rms power sinewaves into resistors.

That is quite different for asserting that you actually *are* experiencing limiting. You may well not be doing so, and your preference is for other reasons. The above is just a possibility that can arise in some circumstances.

Nor, so far as I can see, has anyone said you should not like what you do. The amp delivers the result you like, and hence is doing the job you chose it for.

BTW the irony of this is if I'm dismissed as a 'meter reader' for pointing out that reading a meter may be misleading. 8-]
 
DimitryZ said:
Outside of professional interactions, it is perfectly fine to have a discussion with "outsiders" who know nothing about your field. What is quite boorish us to use non-proffessional forum for pseudo-proffessional self-affirmation.

Proffessional who is comfortable with his/her level of accomplishment and knowledge doesnt need to ridicule anyone.
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Ah well I wasted my time there then as I couldn't disagree with you more strongly on most of that.
 
Jim,

It’s possible that a teapot is orbiting the sun, but it seems unlikely, more unlikely than my Stingray having an electrical conniption into GRFs, but unlikely all the same.

Joe
 
Jim,

Jim Audiomisc said:
So far as I can see, no-one is either 'ostrasizing' you or saying you *are* 'wrong' about the levels you use.
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h.g. said:
If Joe and his meter are to be believed he is listening at 25-30 dB below these levels...
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Maybe it was a slip of the keyboard — suggesting *I* was lying — when only an inaccurate meter was being suggested, but h.g. has had plenty of opportunity to say otherwise if that is indeed the case. If it's just the meter's accuracy that's being questioned I would have written, "assuming Joe's meter is accurate..."

Maybe you'd react differently to being called untruthful, but I don't consider that friendly forum banter.

Anyway, I've gone on enough about this. In short, my Stingray and GRFs sound great, but I am considering an amp with tone controls because I typically listen at levels where a bit of bass and treble boost would be good things. (And I'm only considering an amp with tone controls because I may have some fun money in a while for such a purchase.)

Joe
 
Joe P said:
Jim,





Maybe it was a slip of the keyboard — suggesting *I* was lying — when only an inaccurate meter was being suggested, but h.g. has had plenty of opportunity to say otherwise if that is indeed the case. If it's just the meter's accuracy that's being questioned I would have written, "assuming Joe's meter is accurate..."

Maybe you'd react differently to being called untruthful, but I don't consider that friendly forum banter.

Anyway, I've gone on enough about this. In short, my Stingray and GRFs sound great, but I am considering an amp with tone controls because I typically listen at levels where a bit of bass and treble boost would be good things. (And I'm only considering an amp with tone controls because I may have some fun money in a while for such a purchase.)

Joe
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Plenty listen around 70-80dB average-it's an 'average' for gawd sake-guesstimate whatever this will translate to about half a watt peaks into your 100dB/W GRF's at the distance you sit.
 
Joe P said:
That's very likely what I'm hearing with the GRFs and Stingray — an intentional bass lift — because they really sounded endemic with a Naim 250.
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Autocorrect strikes again. Did you mean "anemic"?
 
Yank,

Actually, I was aiming for cromulent. Or maybe emollient.

Joe
 
Joe P said:
Jim,





Maybe it was a slip of the keyboard — suggesting *I* was lying — when only an inaccurate meter was being suggested, but h.g. has had plenty of opportunity to say otherwise if that is indeed the case. If it's just the meter's accuracy that's being questioned I would have written, "assuming Joe's meter is accurate..."

Maybe you'd react differently to being called untruthful, but I don't consider that friendly forum banter.

Anyway, I've gone on enough about this. In short, my Stingray and GRFs sound great, but I am considering an amp with tone controls because I typically listen at levels where a bit of bass and treble boost would be good things. (And I'm only considering an amp with tone controls because I may have some fun money in a while for such a purchase.)

Joe
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Did you consider putting in an outboard tone control unit either downstream or in the processor/tape loop, if Manley has one?

Folks here will probably laugh at this approriosly, but you can try one for short money:

FX-Audio TUBE-03 HIFI Treble Bass Buffer Tube Preamplifier Black https://www.amazon.com/dp/B07D9G153F/?tag=pinkfishmedia-20

I tried a version of this unit without tone controls and i can report that it worked well and had vanishingly low noise.
 
Dimitry,

The Stingray has a tape monitor loop so I could add an outboard tone control or equalizer easily. I would be willing to go a bit more upscale. Any recommendations?

Joe
 
Joe P said:
Dimitry,

The Stingray has a tape monitor loop so I could add an outboard tone control or equalizer easily. I would be willing to go a bit more upscale. Any recommendations?

Joe
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I have tone controls on my preamp so the cheapy unit is the only one i came accross. I am sure you can find a true audiophile unit at 10 or 30 times the price!

If you get the $50 one, make sure you get matched pair of better tubes:

Riverstone Audio - Tested/Matched Pair (2 Tubes) 7-Pin GE JAN 5654W Fully-Tested Vacuum Tubes - Upgrade for 6AK5 / 6J1 / 6J1P / EF95 - GE 5654W Platinum Grade Pair https://www.amazon.com/dp/B01BFJDTW0/?tag=pinkfishmedia-20

You can also contact Manley Labs and see if you can get them interested in developing such a unit.
 
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