0.9V to 2.0V four-way amp for MiniDSP 2x4

[Tromperie]

0.9V to 2.0V four-way line level booster amp for MiniDSP 2x4

I bought the MiniDSP 2x4 years ago and am yet to put them into service. The problem is the 0.9V output does not suit my setup. I have searched the forums and found nothing suitable.

Can anyone suggest a specific fully working circuit I can use to design and fabricate a PCB, please?

 

[timbarnes]

There are a lot of gain stages you could use. You can get a simple 5532 op amp gain stage on Ebay, or build your own. You could build the Nelson Pass BA-3 gain stage (or two if you need all four channels). Nelson also published some single transistor gain stages like the JFET BOZ that you could try.

I have the Minidsp 2x4, and as I only need the output from two channels at present, I have it sandwiched between the two gain stages of a Rod Elliott Project 88 preamp. If I needed four outputs, a pair of Project 88 preamps would be a good bet.

I'm sure there are many other options, but these are a few.

 

[EUVL]

Just use a quad opamp and set the gain to 2.2 if you must.
For example OPA4134, LM837, .... etc.

But then most preamp/amp should be able to live with 0.9Vrms.
Just turn up the volume by 6dB.


Patrick

 

[Tromperie]

Patrick,
The MiniDSPs will be in the speaker boxes and feeding the amps directly.