Bypassing A Preamp With Volume Pot In Amp


I see preamps as a convenient tool to control the volume of multiple sources. It only adds another link in the chain. It also adds to the cost of your system because you will need other pairs of interconnects and a power cable.

I was thinking about completely bypassing a preamp by adding a volume pot or a resistor based stepped attenuator into the amp, greatly reducing the signal path from the source to the amp.

The only detriment I can think of, is switching the interconnects from each source which is as troublesome as switching out a disk from the CD player.

Please chime in with your opinions and especially your experiences with this "issue".

The volume control I have in mind is the Khozmo stepped attenuator using 2 Vishay TX2575 resistors in a hybrid tubed/ss amp.
c_avila1
Lse, it's not a pot (potentiometer).

It's just like a direct connection between source and power-amp with none of the contacts or preamps active components in the signal path, like a pots very lightweight wiper contact or switched resistor pots contacts in the signal path.
It's just a single fixed soldered resistor, that just happens to be able to change it's resistance value by being light sensitive.

It's the most transparent, uncoloured, dynamic way of getting the signal of the source to the power-amp, without any active tube or solid state components or contacts in the signal path.

You can read all about in these two threads.

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1276356977&&&/Lightspeed-Attenuator-Best-Preamp-Ever-

http://www.diyaudio.com/forums/analog-line-level/80194-lightspeed-attenuator-new-passive-preamp.html

Cheers George
I've installed a Goldpoint stepped attenuator in my amp and soldered my interconnects directly to it. My CD player and phono pre have no trouble driving the amp.
Correct Jetrexpro, nearly all sources these days have output voltages higher than what the maximum input voltage is needed to drive amps into full output.

So there is no need for preamps with gain.
And if you have a source with low output impedance (<200ohms) as well, which most are anyway. All you need is a passive volume control, does'nt matter if it's inside the poweramp or outside connected by a meter of quality low capacitance (which most are) interconnect.

Cheers George
«Georgelofi» LSA acts as a conventional resistance, with respect to the set of impedances?
Changing interconects not scare me, but adjust the volume behind the amp, yes. Unless you have great discipline when it comes to listening volume.
@Jetrexpro: Can you please tell us about your experience and opinion with having the Goldpoint stepped attenuator in your amp. Did you use a preamp before the Goldpoint? What are the benefits and detriments of the Goldpoint attenuator?