Amp and CD player both without volume controls

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#25
355F1 said:
One more question, I cannot find a good quality Hammond step-down transformer
115VAC to 100VAC.
Click to expand...

You can use a small transformer, rated at 120VAC to 12VAC, with the 12VAC winding connected in series
with the primary of your transformer. WIth the right phasing, this will lower the voltage on your transformer's
primary to 100VAC. The small transformer should have the same (or higher) secondary current rating as
your transformer's primary winding. The small transformer can be in an external enclosure. The original
equipment does not need to be modified internally at all.
 

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#26
355F1--Looks typical 70,s seems to be highly prized now , I hope its got top end tubes in it as I remember cheap versions of 12AX7 /ECC83 were being made then .
The 12AU7/ECC82 will probably be for the headphone out as it has 10x the plate current of the 12AX7.
Going by the prices online that's pretty reasonable make sure its with the wooden case plus paperwork.



As I said make sure its fitted with quality tubes I have tested 1000,s of those types on my AVO tube tester and at the time the small companies making them just weren't up to scratch that's why I always bought Mullard you could rely on them , I take it in the USA it would be RCA .


For the record I have a 70,s very large black solid state Sansui its permanently connected to my TV , has been for over 20 years --never off and NEVER failed try that with some of the modern stuff.
 
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#27
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#28
I have received my Schiit Sys volume control, simplicity at its best, I connected it between my Berning ZH-230 and my Meridian 507 CD player. I'm very happy with it.

Hope it works as well with the phono head amp that I'll purchase.

Thanks for the suggestions.
 
#30
I am liquidated, I want a vacuum tube pre not SS.

This is a pre with an attenuator. Are you sure that it won't work?

I posted this pic in a previous message. A friend of mine who travels to Tokyo sometimes brings a rare component. He has another but with 2 attenuators, one for each channel.
 

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#33
355F1 said:
This is a pre with an attenuator. Are you sure that it won't work?
Click to expand...

Typically the topology for a line stage is volume control -> voltage amplifier.

When the volume control is 10k as in most ss line stages, this would require
a source with at least a 10uF blocking capacitor, as well as low distortion
into a 10k load, and an output impedance of 3k or less. This would be difficult
for most tube phono stages.

In a tube line stage, the volume control is typically 100k to 250k.
A tube phono stage should normally be able to drive such a load.
 
#35
Hello Horacio,

I do not know if your system has enough gain - but it probably does.

Therefore, the Goldpoint passive preamp you noted should work
between the two signal sources and it's output connected to
your tubed power amplifier - should work! If it did not, we will
buy it back with a restocking fee - and you would loose shipping
charges too.

Arn Roatcap
Goldpoint Level Controls
Sunnyvale, California
(408) 721-7102
 
#36
Rayma,

Does this solve the problem?

That stock Goldpoint SA2-47 is usually 25K which, according to Goldpoint, is typically optimum, but at my request they can put a 47-position 10K, 50K or 100K unit in it instead if I say to.
 
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