Combining an AVR with a stereo amp: adjusting volume for surround

[mcgee]

I'm thinking about adding a separate stereo amp to my current CA AVR. I would run my floorstanders through the stereo amp which would be linked to the 6.1 pre-amp outs on the AVR.

My question is this...

When watching a film/tv, how easy is it to adjust the stereo amp volume to be in accord with the volume of the satellites/centre/sub? That is without a microphone and the use of the self-automated volum adjusting systems that you can get on AVRs (mine doesn't have it)?

Do people just fiddle with the stereo amp volume setting till you get the volume level which sounds right to your ears?

Cheers

[Bossk128]

There are stereo amplifiers which have an input which is fixed gain, sort of a direct pass through which the volume knob has no control over. Off the top of my head I think the Musical Fidelity A1000 stereo amp has this, but there are many others.

If you use any stereo amp, as I think you already know, you'd always need to set the volume to the calibrated value before watching films.

[mcgee]

Cheers. The calibration of the stereo amp volume is the issue really - how to do that when you don't have a microphone or sound meter?

[dablk]

How about this idea...not that i have tried it.

Hook up as you have planed however hook left speaker to av amp left channel as normal. Then hook up right speaker to stereo amp right channel.

Run the av amp in stereo mode.
Play a cd at normal volume so only the left channel works.

Now turn up the stereo amp to balance the right channel. Note the volume setting you reach.

Turn everything off and rewire for the stereo amp. Turn up the stereo amp to the volume noted. Play the cd again through av amp into stereo but now the stereo amps only being used as a "power amp" with volume control from the av amp.

It sounds cowboy but the logic seems to work in my head at the minute. To me that will give you an idea of what output the av amp would be expecting from its front speakers at any volume setting, and should be balanced with the rest of the 6.1

[scrufftyguy]

I've been considering this too and from what I can gather the easiest way to do this is to get an all in one remote.

I asked on the remote forum about this and people seemed to reckon the Harmony One can adjust both an AV receiver and a stereo amp at the same time if it's all set up correctly! Not sure about other remotes.

It might be worth you asking a few questions over on the remotes forum!

Ade

[mcgee]

Thanks for the ideas guys. I shall give it a go.

[proux]

Originally Posted by Bossk128

There are stereo amplifiers which have an input which is fixed gain, sort of a direct pass through which the volume knob has no control over. Off the top of my head I think the Musical Fidelity A1000 stereo amp has this, but there are many others.

If you use any stereo amp, as I think you already know, you'd always need to set the volume to the calibrated value before watching films.

Also most Arcam amps for Alpha8R onwards, and I think some newer Cambridge Audio and Naim. There are some old threads on this.

[Import racer]

Hi,

If understand correctly you are going to hook up an integrated amp for the front speakers, i have to say and please don't take it the wrong way,
but its very easy if there is a volume control on the stereo amp (and its not a power amp which would be fixed anyway).

Listening to music would be where i would start,
I have my pre-amp at around 3/4 and seems almost about right as you want the max power the amp(s) can give but without ever into distortion then very slight adjustments, then i balance the others to main speakers on the av amp,
then the sub(S)

Then try for movies and the volume should be in the same place, although personal preference may mean you adjust it slightly, but i don't need to change the front volume gain at all once you ve found the perfect level for the fronts.

Much quicker than all that below and you will know when it sounds right, very quickly, as its eithier not loud enough or too low.
And you should probably leave the av amps levels the same to start with as you have propably set them already to there best settings then fine tune them after setting the fronts as mentioned before.

Really not sure why you would need a remote though, or is it laziness.

Should sound real nice if you choose a pretty nice sounding quite powerful amp.

[Mark.Yudkin]

Many modern stereo integrated amplifiers have a processor mode input which you configure to have the same gain as the AVR (details below). The processor mode bypasses the integrated amp's volume control allowing you to control overall volume from the AVR. The important thing therefore is to buy an integrated amplifier having a processor mode input, anything else becomes a royal pain in the you-know-where (although it can be made to work if you already have an older stereo amp - see Import Racer's post).

To calibrate the processor mode you use an SPL. The dealer who sells you the new stereo integrated amp will probably lend you one, and they're not expensive to purchase either. Plug the L&R pre-out from the AVR to the processor mode input of the stereo amp, set the L&R trims on the AVR to 0, then adjust the processor mode input's gain until the SPLs are correct. If the AVR has calibration test tones, this will be 75dB. Then recalibrate the surrounds and centre (and sub) to 75dB. Sub calibration is actually messier as you need to compensate much more for the room - search the sub forum for details.