Multiroom Audio Amp questions

[znelbok]

I have a Pi running as a sqieezebox now and its going OK - some say the sound quality is poor out of the Pi and a DAC should be used, but to me its not an issue as background music.

What I want to do is place a small setero amp in each zone with a SqueezePi. When I wired the house up I made allowances for small amps to be wall mounted in the top of wardrobes and pantry's etc to power speakers in each zone - it was always going to bea distributed amp system.

Does anyone know of any small wall mounted amps that would be suitable. I want something that preferable has auto on when a signal is detected. Volume is not required as the SqueezePi has volume control.

Would a car amplifier be OK. Most are rated for 4 ohms, but thats probably so the power rating looks better than at a standard 6 or 8 ohms that house speakers are typically rated at. My training tells me that an 8 ohm speaker will reduce the power, but also make it easier on the amp so it should be OK.

Interested to hear all ideas

Mick

[pjgregory]

How about using powered speakers rather than an amp and a speaker? There are a lot of these on Amazon varying from the cheap and nasty to some reasonable nearfield monitors. Of course you get what you pay for and you have not mentioned how much you plan to spend on each room. There are some nice Behringer units that also have a SPDIF input as well as RCA sockets, so you might be able to go directly from the Pi if it has this tyrp of digital output.

PJG

[znelbok]

yeah, not sure on the combined unit idea. When the amp fails you need to fill the hole with something - like a speaker.

As for how much, well its not going to be expensive, otherwise I would not use a Pi. A built in DAC would be ideal, but not necessary.

Can use amazon either - they don't deliver here

[sic0048]

Have you looked at the digital amps that are available today? I haven't looked at them in a while, but I know they are very small, efficient,and fairly inexpensive.

[Deephaven]

These don't really have auto on, but they don't really use power. If the Pi audio quality is enough then it is pretty easy.

I use one of these in my office powering a set of $800 speakers. It does the job, albeit a bit lacking in balls. You could just rail the volume knob and hide it.
http://www.parts-express.com/pe/showdetl...er=300-380

If you needed more juice, this is an option for some more dough:
http://www.parts-express.com/pe/showdetl...er=300-383

Not used one of these, but they are dirt cheap. You would need one per speaker, but could be hidden in wall with the speaker.
http://www.parts-express.com/pe/showdetl...er=320-552

Tons of other options. The first two I know work as I've used them, but in general PE does a nice job with their stuff. Obviously no automation hooks, but I'd just let them run at a level they can without distortion and use the Squeeze/Pi to do the rest. The main determination in what to pick to me here is what wiring has already been done.

[znelbok]

Thanks

So do you leave the amps on permanently or do they autoswitch on and off?

Had a look at Amazon out of curiosity and Boss Riot amp is sor tof the form factor I am looking for. It has a contact for a on/off like all car amps, but if leaving it on is an option then I can work with that.

The prices here in aus are ~$70au plus delivery, so no where near as cheap as amazon, but that is the sort of money I think is suitable for the application.

[Deephaven]

I leave mine on, not super power hungry. If you needed to turn it off and on you could add a relay, most of those use DC supplies so a simple el cheapo Bosch style relay would work.

The Boss stuff is classically horseshit. Not that I linked anything that is uber audio quality, but much more respectable. I would also assume there is something akin to PE or Monoprice down under that should have something.

Unless you find a full range class D or T amplifier for a car, I'd avoid them as they will then create a power supply problem for you if they have any power at all. And to save you some time, you aren't going to find an ultra small T or D car amplifier...I shouldn't say that ultra excusively, but I sure haven't seen one and have looked many a times. Full range class D's just started to hit the mobile audio market about 2 years ago, at least en masse when the Polk/Hertz/PPI/NVX all came out sharing Class D boards.

The only disadvantage with on all the time is you have to be careful with ground loops to make sure there is no noise. ANY noise drives me nuts so I do that anyways.

*the Boss stuff that was built by Zed & Steven Mantz of course were quality...but that ended a long time ago as far as I know

[znelbok]

A bit of searching and I have found some Dayton DTA-100a for a similar price to that in the US. I think I will go with them. Not the easiest to wall mount but not impossible.

Thanks for the feedback