An unusual mounting, but that does not ensure strain relief. You mainly need enough cable to flex freely
when connected, and also not be bent as it leaves the connector housing at either end.
Sometimes there is a spring or similar on the connector to reduce any tendency toward sharp bending.
https://www.markertek.com/product/t...h-spring-strain-relief-for-1-4-inch-o-d-cable
Why even bother doing that.
Here is the input to that amp.
100K would be the attenuator
which PS Audio preamp?
But it doesn't matter they would spec the minimum (which would be like 100 ohms, more likely expressed as >100 ohms)
The designer said it wouldn't work properly unless the impedance from the source was lowered to 600 Ohms
The PS Audio is a IV-H.
no, you wouldn't want to do that. the input filter would not like it. What you have should work fine together without an attenuator.
The Onkyo preamp had issues with connecting to certain amps.
Yes, I read what Tom said, and he has issues saying things clearly like always.
Your preamp is fine.
Its designed to drive 600 ohms or higher
And if you really want to know, the preamp you bought would need 50K or higher anyways to work nicely. looking at the schematics
Got it. But I still want to test the amp with a passive attenuator that is as close as possible to the 600 Ohm rating. The question is how to achieve it.
The obvious solution is to add a Buffer.
The preamp/power amp combination you mention, including unbuffered filtering at the input, then straight feeding a 100k pot is poorly suited for what you want to do.
Sorry, but "you have what you have".
Actually, I don't technically own the amp yet. It is a Christmas gift from my family which we are in the process of buying.
I didn't realise that the input impedance was so high until I read the designers comments on it.
I actually like the idea of a passive buffered preamp, but quality audio transformers cost a lot of money.
Well, it appears that the problem with low impedance attenuators is that most sources don't work well with them without a buffer.
So I need to explore different buffering ideas to come up with a solution.
So I need to explore different buffering ideas to come up with a solution.
OK, so I need a solution that will allow for a high impedance friendly input (buffer), and a low impedance output. And since a pot outputs less impedance tha it's rated for, 1K may be sufficient?
When you get it , hook it up and tell us how it behaves, and stop worrying about it.
I found a post with measurements which indicates that you are likely correct. My DAC has a strong discreet B1 buffer, and my phonostage is an EAR 834 clone. This leaves my ASUS XONAR DS soundcard with its BB2107 opamp as a possible weak link.
My speakers are a set of Acoustat 83dB hybrid electrostatics!
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