TKD pot and other mods

[Riggers]

When I spoke to the guy from ETI I asked him about the screw retaining design on the internal side and mentioned that in the World Design amp solder tags were used to connect OPTx and feedback wiring to the binding posts. He said the the screw retainer was a better idea as it avoid unnecessary capacitance.

Phil.

[Richard]

Interesting thread Phil.

Looking at the pictures I'd re-arrange the ground connection for the 10R resistor so it is soldered to a better and more secure termination on signal ground.

Those post screws don't look like they're designed to clamp more than one wire and the resistor lead doesn't look to be clamped.

I don't understand the reason or importance of what may be a couple of pF difference in a speaker post. There will be massively more in the speaker cables, and it doesn't matter to the power amp anyway, but any further info they gave you would be interesting.

Re. the TDK pot, glad you like it. I've not tried it but it sounds like you may not want/need to shunt it as you say. The Alps shunt in the FAQ is only a suggestion for anyone wanting to try. It offers a variable attenuation of any excess gain. Pre3 is supplied with the Alps so a couple of resistors makes for a cheap tweak. The sound quality may or may not be to taste of course.

[bikerhifinut]

Originally Posted by Riggers

When I spoke to the guy from ETI I asked him about the screw retaining design on the internal side and mentioned that in the World Design amp solder tags were used to connect OPTx and feedback wiring to the binding posts. He said the the screw retainer was a better idea as it avoid unnecessary capacitance.

Phil.

Audiophoolery..................

[bikerhifinut]

And I'm 100% with Bob on regulated PSU, amplifiers only modulate the supply voltage so a nice noise free supply is the first place to start. My opinion only of course and a good unregulated choke smoothed supply can do the biz too, although I do feel in areas like low signal low noise Phono stages you really must start with a good stiff steady HT.
As to shunted pots and in turn shunt attenuators, again I'm with Bob. I've tried the tweaks and always return to a standard potentiometer or similar switched design. Because I like to have remote control of the volume I'm pretty much restricted to a motorised pot, but i did use a switched ladder attenuator (is that the right term, where two ganged individual switches switch in pairs of resistive dividers?) and I think that was pretty much about as good as it gets. Whats nice about those is you get a proper potential divider action which keeps the input resistance reasonably steady and the channel balance absolutely cock on.
But hey its a free world and if what you have done makes your system sound better TO YOU then stick 2 fingers up to the rest of us and enjoy.

A

[bob orbell]

Stick two fingers up, must agree Andy. Off topic, but if you read this A, I sent you an email some time back with regard to a Quad tuner, please get in touch. Bob

[MarkL]

I fitted a stepped attenuator to my pre III when the alps pot failed.
It is a shunt version.Just reading some of the previous comments, I am wondering if this is a problem for the amplifier?
I did get an immediate improvement in sound, but I suppose that could have been down to the dodgy pot