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View Full Version : Help me set up a Multi-Zone whole house audio system



m00j
November 27th, 2004, 03:04 AM
Hi,

I am setting up a distributed audio system in my new house, with cabling through the ceiling and ceiling mounted speakers (all running off car amps and a PC running Media Center).

I want to have two PDAs connected at the same time, so that we can easily control music in two zones at the same time (which do not have PCs). Can I do this? I think it will work, but wanted to make sure before I spend the money on the PDAs.

Thanks

danward79
November 27th, 2004, 05:26 AM
Hi,

Yes, you can do this.

Out of interest, Do you have any more details on how you will set up your system. Are the amps going to be located at the rooms, or are they going to be located near the pc with long speaker cables?

Are you using single ended rca phono leads? or Balanced Audio leads and distribution.

m00j
November 27th, 2004, 05:39 AM
I have run large gauge speaker wire to each of the rooms. I will have the amplifiers at the computer end. Most of the runs are not too long - about two large room lengths max.

I have a corner under the stairs where the computer and amplifiers will be placed. It gets good cooling as it is accessed from inside the wine cellar.

I was planning on using car amps, run off a car battery with a charger. That way the audio quality will be purer.

Any ideas are welcome. The speaker wire is laid, and I have the main computer (without the sound cards) but everything else is still to be purchased.

danward79
November 27th, 2004, 06:09 AM
have run large gauge speaker wire to each of the rooms. I will have the amplifiers at the computer end.

I am glad you said that! Single ended phono type leads on large legths tend to pick up alot of noise.

You say audio quality will be purer... Be careful, that depends on if you have the charger running all the time, and on the quality of the charge.

Perhaps a better solution would be to build a decent 13.8 Vdc PSU? With plenty of regulation, and noise suppression and ample smoothing caps?

That is unless you intend only running the charge when you are not using the amps. In my experience, chargers do not normally have a very well regulated output.

Just my thoughts.

m00j
November 27th, 2004, 06:16 AM
I have not worked out how to do the battery charger fully yet. If I use 13.8V regulated PSUs the cost will go up and they will have to be pretty beefy to power the amps.

I realise that I should not have the charger running when the car battery is charging but I can't work out another way to power it all! I may be able to rig up something that will cut the power to the charger when there is audio playing.

I am planning to use car speakers in the roof. Nice and loud, and I can get good quality ones cheap.

For the PDAs I am planning on using one or two Toshiba E800 PDAs with Wi-Fi built in. Nice large 4" 640x480 screens :D

danward79
November 27th, 2004, 06:53 AM
Your problem is an interesting on. Have you thought about some cheap hifi amplifiers?

I personally would be a little careful about the battery and charger bussiness. Also remember, when you charge a battery, you must allow it to vent, and watch the electrolyte level.
venting is normally / should be done by removing the cell caps.

You should have a look at Mastiff's website, he is a multi-zone guru. I can't remember how he did it thou.

I was lucky I had a spare amp I built, which I use for multizone, to my bathroom!

m00j
November 27th, 2004, 06:58 AM
The biggest problem is that I want to do around 8 zones.

And if I use sealed Lead Acid batteries I do not need to vent them I thought. Or possibly gel cells (but they are so much more expensive)

danward79
November 27th, 2004, 07:07 AM
If you use SLAB's you will get round the venting problem. They also have a more favourable discharge curve. in that nicad's tend to just drop off. slaps have a more gradule drop off.

They are obviously more expensive as you say. There has been a lot of work in the battery field in recent years, which now makes this a more complex field to explore. Of course most of the work has been pushed along by the mobile phone and portable device markets.

Perhaps you could find a charge that kicks in at a charge level? Or you could have it time activated?

m00j
November 27th, 2004, 07:19 AM
actually, I know I can get a cheap timer adaptor that plugs into the power point and turns on only at set times of the day - we had one for our pool pump in our old house. So I could set it up to charge the batteries each night for an hour or so (just to top it off, as it is not going to get used all the time).

That will probably work quite well. If I am planning a big party that will run late into the night (e.g. new years etc) I can easily go into the room and physically unplug the charger so that I won't get any hum in the music.

Mastiff
November 27th, 2004, 11:05 AM
I doubt that you will notice any difference between car amps and a good set of hifi amps. One version would be simply getting three 6 channel home theater amp (I believe there are some good ones from Outlaw, Rotel is another variant) and use two channels per zone. That will give you one zone to spare. To me that would be the sensible solution, too much can happen with chargers and car batteries.

danward79
November 27th, 2004, 11:10 AM
I must admit I would agree with Mastiff. Batteries are potential for trouble.

Mastiff
November 27th, 2004, 11:12 AM
You mean it's that hard for you to agree with me? What have I done to you lately? :wink:

danward79
November 27th, 2004, 11:16 AM
:P

m00j
November 27th, 2004, 04:39 PM
I was wondering how long it would take before you replied Mastiff, I have been browsing these forums off and on for many months so far and it does not take long to see that your an expert on this subject! Your setup looks very nice.

Would I just use standard home theatre amps? I know you can get specialised amps that are multi-channel in multi-channel out and designed specifically for applications like this, but from what I have seen they are very expensive.

Many of the rooms only have 1 speaker, and the rooms that have more are still going to have mono sound through them. So would it work if I got a powerful 6 channel home theatre amp and then run each channel to six different zones? I am worried about if the amplifier will like driving all those 4 Ohm speakers or if it will give up the blue smoke.

Also, there is no known problems of using the PDA to control volume is there? I would probably make it control the line level out on the soundcards so that I do not have to have some sort of hardware device to do it as well.

Thanks for all the help everyone.

Mastiff
November 27th, 2004, 05:45 PM
Thanks for the praise! Yes, I'm often around, but lately I've been working a lot, so I'm not as sharp as usual...


Model 7100 7-channel Amplifier
A moderate price never had such a reward. The Model 7100 delivers 7 channels at 100 Watts each, allowing playback of the most recent sound formats without breaking the bank. $899

From www.outlawaudio.com

I don't know what you consider expensive, but I would not consider this expensive at all. And look at all the hazzle you save yourself. It's rated at 7x165 w in 4 ohms, so I don't think you would have problems with your load.

As for volume control, that should be no problem at all. All you have to remember is to set the volume of the amp so that max volume from the sound card won't send your speaker cone through a floor or two. Accidents can and will happen, especially in the first period. We've all been there. It took me a year or so to make my wife use the systems.

m00j
November 28th, 2004, 02:46 AM
Yeah that seems a bit pricey.

I live in Australia as well, I have seen a few amps like that around on the web, but emails to the stores proved to be useless!

I work in an electronics store as well, so I can get standard consumer stuff a lot cheaper, including car audio. For example, a high quality 4 channel clarion car amp for less than US$150. Two of them leaves me a very substantial amount of money to cover however I plan to power it. I would prefer a device like the one you mentioned, but I don't think I can justify the added cost.

I might look tomorrow to see what they have in the way of amplifiers that may suit my needs. Even if it is a 7.1 amplifier, I would be able to use each channel as a seperate amp for a zone, and then use the main volume control to simultaneously control all zones max volume at once.

I won't be able to reply until the end of this week - going to the beach (yes, it is summer here in Australia :D)

Thanks for all the help so far guys!

Ben S
November 28th, 2004, 09:05 AM
Just checking here, but for all of the speakers you need independent zones with their own sources, etc?

My home is setup where I can only have two zones (it's an open floorplan), so I have one amp with a speaker selector that ensures that the amp sees a 4 ohm load, then from the speaker selector it goes out to 9 sets of speakers and volume controls.

m00j
November 28th, 2004, 09:20 AM
For zones the perfect configuration would be:

The dining room, living room and deck as one large zone, but each with individual volume controlled via the PDA (as obviously we don't want to be playing music out side all the time). I can probably even join the dining into the lounge as one room as it is open plan in that part of the house.

Then the three bedrooms and the office as separate zones, which will be able to have separate songs playing.

There is also a rumpus room, which is a bit different as it will also have a tape player in the room which is going to be hooked up some how as well (quite possibly there will be a selector switch at the tape player that can be changed over between tape and this audio system).


I realise this is probably a very ambitious design, and I will most likely roll it out in stages (e.g. get it working for the living room, and then add the deck, then another zone etc).


What sort of speaker selector is it? Is it just built into the amp?

This will be the last post I can make before going on holidays for the week, afterwards I think I will start a new thread (or rename this one) dedicated to working out all the requirements to get this system up and running.

Ben S
November 28th, 2004, 09:38 AM
What sort of speaker selector is it? Is it just built into the amp?

Something like this (http://www.smarthome.com/8267.html). Mines a little different.

A few of my volume control units also have impedance matching (that works), so I run those 3 through a simple distribution panel to the speaker selector.

Before this I had all 9 going through the simple distribution panel to the amp, and after 2 months the amp caught on fire. Oops!

Mastiff
November 28th, 2004, 12:39 PM
OK, if you consider that expensive I'm afraid I'll have to bow out of this one. Of course the other way would be to do what I have done for one of my zones (my son Kevin's room): buy used, older amps, usually integrated amps (with both power and pre amp) are less expensive than pure power amps, also receivers can very often be the cheapest of the lot - you can get old NAD receivers pretty cheap in most countries, and they are very nice sounding), but I will still say that messing with car amps indoors is too much trouble and too much potential problems. Also if you consider a car amp high quality when it costs you around 150 dollars (I recon it won't be more than 250 dollars regular price), we're not speaking the same languague. :wink: I have a Soundstream two channel amp that I consider lower midrange, and that cost around 400 dollars four or five years ago, I believe... High quality car amps with four channels for me usually starts around 800 dollars.

danward79
November 28th, 2004, 12:46 PM
You could try some kit amps?

Velleman do some very good basic IC based amps, that are mounted on the heatsink, they are fairly cheap, EASY to build and come in stereo form. This is helpful for when they fail, you don't loose the whole lot.

Normally if these do fail it is just a case of changing the IC. I only every had one amp I built fail. That was due to an IC with Static damage after a flight.

You could then mount them in a large enclosure or individually.

It is probably the choice I would take.

m00j
December 3rd, 2004, 01:00 AM
Well I am back from my holidays :D

Mastiff,
I don't mind spending that much if that is how much I need to spend to get good quality sound. I am probably going to go with a proper multi channel amplifier now anyway as it seems to be the best way to do it (I had completely forgot that cheap car amps sound poor!)

danward79,
I was planning on building the Velleman kit amps originally, but then I still have the problem of how to power it.

Ben S,
I could see smaller versions of that coming in handy. A 8 speaker one would come in handy if I could turn specific speakers on an off as well.


In other news, just before leaving for the beach I picked up a PDA to control it all. A Toshiba e805. Yes, they are an end of life model and the processor is a bit slow now but was a bargain at around US$385. It has the nice large 4" VGA screen :D

Now I have all the control components I just need the soundcards, amps and speakers!

sic0048
January 5th, 2005, 04:55 PM
Well, I would also suggest that you look at recievers if you are looking for an inexpensive option. The problem is that can't really run mono channels through them. What I mean is it is obviously easy to run a mono channel, but you will not be able to run two seperate and different mono channels at the same time from the same receiver, so why just wire for stereo in that case. You will need one receiver for each different zone whether you want stereo or mono and you will probably be limited to four speakers max from each receiver, but that is going to be a variable of the receivers you use.

I would mount the receivers near your computer and have the computer hooked up to one input. I would also incorporate an IR system into the mix with NetRemote. This isn't a whole house IR, but would simply extend from the computer to your recievers. This way you could control the volume using your PDAs (your computer would send an IR signal to the receivers just like the normal remote control would). You could control the receiver to change inputs (like switching from the computer to a built in radio reciever, etc) in the same way.

However, in your romper room, I would find a spot to place that reciever in the room. That way you could hook your tape deck up and have access to it. It would simplify the system in that room because it would act like a normal stereo - no need for a PDA to control it. Now you could stick the tape deck in the closet with the other receivers, but then you wouldn't be able to switch tapes very easily.

m00j
January 5th, 2005, 08:34 PM
Hehe, very hard to change tapes - the computer is going under the staircase which is accessible through the wine cellar,

I am looking at getting one of the ROTEL multi channel amps now.
http://europe.rotel.com/products/multichannel-power-amplifiers.htm

Probably the 6 or 8 channel one. They should be able to handle my needs (and I can source them in Australia :D).

Still unsure for speakers though. I don't know if I should get the proper in-ceiling ones or car speakers to mount in the ceiling. My other thought is to use proper speakers and buy some ceiling grills from my local electronics store - most likely the best of both worlds in terms of sound quality / price.

*edit* changed the thread title to reflect it beter