Surround setup

[chelgrian]

I wouldn't touch that solely based on their use of the word "Audiophile" - next they'll say it only works with triple refined 4mm gold oxygen, nitrogen and carbon free cable.....

 

Ha well the Cambridge Audio CXU is exactly the same player rebranded and with the analogue audio removed and a £50 price increase. Go Figure.

 

I just bought a new multi channel amp, finding a correctly designed one with output protection was a chore, apparently the latest fad is to remove relays in the name of sound quality....

 

It turns out that the kind of home theatre person who has a equipment rack in a different room and can therefore put up with fans has given up on 'audiophile' amps completely nowadays and they all buy Crown DriveCore.

[Biskit]

Thanks for all the pointers, I am going to go with the unit linked to earlier. Final question - as alluded to earlier, the ability to control overall volume level is tricky (I am using a rather basic mixer without VCAs). Moving the various faders together is a possibility, but is there a product which is essentially a stand-along multi-channel VCA, to allow overall volume to be controlled without mixing all the signals back together? I've tried a search but am obviously not using the correct search terms I don't think.

 

Thanks!

[sandall]

Back in the early days of stereo on TV the preferred method of ganging faders was a (no doubt expensive) bit of clear plastic moulding that clipped over the faders; failing that a plastic ruler did the trick. If you can set the presets so all the faders are at the same level a 6" ruler will cost you a lot less than a multi-channel VCA.

[Shez]

You might find a multi channel studio monitor controller that will do that. Probably won't be cheap though.

[sunray]

Back in the early days of stereo on TV the preferred method of ganging faders was a (no doubt expensive) bit of clear plastic moulding that clipped over the faders; failing that a plastic ruler did the trick. If you can set the presets so all the faders are at the same level a 6" ruler will cost you a lot less than a multi-channel VCA.

When I was at school we needed to gang 3 stereo faders together for a home brew dimmer (Practical Electronics I believe) and drilled horizontally through top and bottom of all 3 knobs then glued (Araldite)two steel wires in the centre knob which poked through the other 2.

I'm not suggesting the same thing for temporary job.

[Biskit]

As an update, I purchased the SPDIF decoder suggested earlier in the thread, and have been having a bit of a play with it at home. It seems to work well, even outputting rear and centre channels from disks which are only recorded in stereo. One thing I have noticed however, which I'm not sure if it's a fault or 'just how it is', is that the sub output seems to go right up to around 1khz but then cross-over very aggressively, as if it has been done digitally with a brick-wall filter. When PFLing the sub channel, it sounds as if there is a load of distortion around the crossover frequency, which disappears when the centre and L&R channels are added to the mix. This happens with recordings which are in 5.1, and also stereo ones. Not a problem, more an observation - is this normal?

[p.k.roberts]

Does the gizmo you bought have any ability to adjust it's outputs? It's worth remembering that the 'sub' output actually isn't necessarily a 'sub' output at all (in the traditional PA sense) - it's an LFE (Low Frequency Effects) channel. However there is often an option on decoders, to enable smaller 'satellite' speakers to be used, to also filter the LF from the main 5 channels into this output as well (as well as other options such as setting up the system with no LFE/sub speaker in use).

[Biskit]

Does the gizmo you bought have any ability to adjust it's outputs? It's worth remembering that the 'sub' output actually isn't necessarily a 'sub' output at all (in the traditional PA sense) - it's an LFE (Low Frequency Effects) channel. However there is often an option on decoders, to enable smaller 'satellite' speakers to be used, to also filter the LF from the main 5 channels into this output as well (as well as other options such as setting up the system with no LFE/sub speaker in use).

Thanks for that, I had realised (but didn't know before) that the 'sub' channel was different from what we would understand it... not a problem though as I'm mixing it in with the C and L&R to my 'standard' PA. The device I have doesn't have any adjustments available at all, other than to switch between inputs (optical and coax) and toggle between 5.1 and 2.0 output.

[chelgrian]

The LFE channel only ever has sub 125KHz sent to it. As said above a standard decode option for Dolby Digital is 'speaker size' if set to small it redirects bass from the front channels in to the subwoofer.

 

If the gizmo is producing distorted 1Hz in the sub output it sounds like it is doing something wrong or it's been cost optimised and is expected to be fed in to a sub with its own 125KHz cross over.

 

In terms of a multi-channel volume control the cheapest thing would be to pickup a old AV amp with a 5.1 channel analogue input.

[sandall]

Crossover at 125KHz & distortion measurements at 1Hz? That's a seriously wideband audio system :huh:

[chelgrian]

Crossover at 125KHz & distortion measurements at 1Hz? That's a seriously wideband audio system :huh:

 

Argh of course I mean 125Hz crossover point and 1KHz distortion. Sadly I'm outside the edit window now so can't fix my original post.

[chelgrian]

Crossover at 125KHz & distortion measurements at 1Hz? That's a seriously wideband audio system :huh:

 

Argh of course I mean 125Hz crossover point and 1KHz distortion. Sadly I'm outside the edit window now so can't fix my original post.