[sci.electronics] Hi-Fi amplification question.

twiston@prlhp1.prl.philips.co.uk (twiston) (06/23/89)

Why is it that building a good Hi_Fi power amlifier is not as simple as
building a decent class B output stage with a healthy power supply, (overrated
transformer big caps etc) and putting this into the feedback loop of a fast
high voltage op_amp?

I'm confused by Hi-Fi magazines who discuss in great detail the subjective 
merits of two very similar in design amps and manage to pronounce one a 
conclusive victor and trash the other when inside they must be electronically
almost identical. Does anybody know the secret? I read yesterday about a French
design of class A tube amp which retails at over 1000 pounds and sells well,
yet the reviewer stated in his technical report that if he had found such a
poor performance in a 100 pound integrated amp he would have and i quote;
"relegated it to the dustbin". 

If the amp sells well it must sound good or maybe its just a status symbol.
Surely the proof of a good Hi-Fi is that it sounds good to the ear. 
-- 
Wayland Twiston Davies (twiston@prlhp1.prl.philips.co.uk)
Philips Research Labs, Crossoak Lane, Redhill, SURREY RH1 5HA
!@#$%^&*()!@#$%^&*()!@#$%^&*()!@#$%^&*()!@#$%^&*()!@#$%^&*()!@#$%^&*()!@#$%^&*()

wiz@xroads.UUCP (Mike Carter) (06/30/89)

In article <917@prlhp1.prl.philips.co.uk>, twiston@prlhp1.prl.philips.co.uk (twiston) writes:
> Why is it that building a good Hi_Fi power amlifier is not as simple as
> building a decent class B output stage with a healthy power supply, (overrated
> transformer big caps etc) and putting this into the feedback loop of a fast
> high voltage op_amp?
> 
> I'm confused by Hi-Fi magazines who discuss in great detail the subjective 
> merits of two very similar in design amps and manage to pronounce one a 
> conclusive victor and trash the other when inside they must be electronically
> almost identical. Does anybody know the secret? I read yesterday about a French
> design of class A tube amp which retails at over 1000 pounds and sells well,
> yet the reviewer stated in his technical report that if he had found such a
> poor performance in a 100 pound integrated amp he would have and i quote;
> "relegated it to the dustbin". 
> 
> If the amp sells well it must sound good or maybe its just a status symbol.
> Surely the proof of a good Hi-Fi is that it sounds good to the ear. 
> -- 


Quite so on your last comment. WHat makes me wretch, alas being physically
ill, is reading these reveiwer's statements in Audio and Video
publications. 
There is merit to a LITTLE of what they say and claim. Emphasis on the word
LITLLE because I have yet to see or read an article written on stereo 
componentry that said what was needed to be said in as little space as
possible.
One long time fallacy is the difference between a twisted coat hangar wire
and a "Monster Cable" connected to the speakers from the amplifier's
output. The audiophiles would have verbose seizures and go completely
catatonic if you wired their system like that and dared to compare.
 
WHen you get a PROFESSIONAL Audiophile, you'd better hold your hand above
your head....I'm sure your wrist watch isnt scatalogically safe..mine isnt
either...these boys are PAID to sound like their written words are eminating
from the finest Bang & Olufsen BEO 3000 when being read.
MOst of what you will read is feature comparison...very little on solid "How
does it really sound?"
If you wish to sample the cuisine with true conneseur's (sp?) , find yourself
the most expensive audio store and go there wearing a suit.
Listen to several selections...from Brahms to Pink Floyd's "The Wall" and
I'm sure you'l aggree ...it's all a matter of where the volume, treble, bass
and price tag are located.
 
SPare the sufferences of childish sophistry and forget J&W's finest gold
leafed pentode amp. IN the Audio world, you don't always get what you pay
for.
 
As for me, I'm still waiting for an audiophile to pass the test.  ...
put the guy in a room with three identical systems playing the same tune at
different times on the same speakers...only hook up the speakers with some
bailing wire or other suitably horrid substitute and have them indicate
unfailingly several times which one was the barbed wire.
 
It'll never happen.
 
		-Mike
-- 
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= Mike Carter  N7GYX, Phoenix AZ| Q: Why did the Chicken cross the road  ?  =
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