Audio PreAmp - Advice

[goldfinger]

Hi Guys,

My preamp recently died and I'm looking to build a new one and was hoping I could get some feedback on advice on the best way to approach the build layout.

I'm still relatively new and it's first build of a hifi pre so apologies in advance Some info.

I currently have two sources one is single ended with an output impedance of around 100ohm and another that has both single ended and balanced out which is 600ohm.

The amplifier is balanced in and has input impedance of 40k.

I have managed to get my hands on a balanced shunt stepped attenuator 10k which I would like to used. The issue is that with my setup once source can't seem to drive the amp enough passively so I will need to look at an active circuit with moderate gain.

I do have a pair of drv134 I can use in build. But I have a few questions I was hoping I could get some feedback and advice on.

- The input impedance of the drv134 is 10k, now whilst that is seemingly enough to drive both my sources issue is the output caps on one source is tuned for >22k for proper bass response so I'm assuming I will need to place a buffer in front of the line driver?

The line driver does a touch under 6db gain I believe which is close but I think I probably need another 3-4db from another stage to drive the input of amplifier well.

I suppose my main questions are:

1. What is the best way to achieve the preamp stage with stepped attenuator? Stages and sequence?

Source -> op buffer/gain-> line driver -> stepped attenuator - output

Source - > op buffer/gain -> line driver - > stepped attenuator-> buffer - > output

2. Any suggestions on good op amps which will work well for audio preamp? I'm sure there is a lot but given my suggested outcomes and individuals experience would be great to hear people's thoughts.

I'm using a good volume attenuator so want to ensure I do it justice by using quality op amp, Open to  discreet as well I've just stuck to op amp for convenience I suppose

3. Any other thoughts or considerations you might have I need to think about/take into account.

Any feedback or thoughts would be really appreciated.



Thanks all!