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Old January 13th 05, 02:11 PM posted to uk.rec.audio
Iain M Churches
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Default DBT a flawed method for evaluating Hi-Fi ?


"Jim Lesurf" wrote in message
...
In article , Iain M Churches
wrote:

"Jim Lesurf" wrote in message
...


As the result of a phone call, I now know that the amp uses a 211
preceded by a 6SN7 octal.


OK. Can you also confirm that the output impedance *is* as high as around
8
Ohms - as your quoted DF of 1 implies?


No. Happily I cannot:-) This was only a figure quoted to me my Andre, when
he said that some SET amps can have a DF=1. I think we would be most unwise
to assume that this is always the case.

OK. These have a much less 'difficult' impedance characteristic than the
57s. However an amp with an o/p impedance of 8 ohms would still cause a
quite marked change in response as a result of impedance interaction.


Please don't assume that Zo=8 ohms. It may keep you awake at night:-)

They have handles on the side, and were a version for the USA only he
thinks.


I am not sure as I am not a quad 'expert'. but I think that, yes, handles
were something that only appeared on models not intended for domestic UK
useage.


It was supposed top be a "prof" model for studio use in the US.
They were some other improvements, I noticed a bottom edge trim also which I
do not recall ever seeing before. But I am even less of a Quad expert than
yourself.
It is a great many years since I have seen a pair.



Iain