I am looking to build a (dedicated) home theatre in a 16'x19' room with 8' ceilings. This room has a 13' opening at the rear into a slightly larger multipurpose room. I am going to use theatre curtains to separate the rooms.
For speakers I am looking to use the 10.3 paper. I like the mar-ken boxes, are they designed for the 10.3 yet? I found a cnc wood working shop that has reasonable rates. So all I will have to do is glue them together.
For speaker wire I am looking at diy cat5 cables.
I am planning on a 7.2 system. For the receiver I am looking at the Yamaha Aventage.
For subs I am looking at the Rythmik servo CI 15" sealed. I am hoping they will not always be needed.
I am looking to use a acoustically transparent screen with a projector. It will be at least a year until it is built so I haven't picked one out yet. That technology seems to change rapidly.
For speakers I am looking to use the 10.3 paper. I like the mar-ken boxes, are they designed for the 10.3 yet? I found a cnc wood working shop that has reasonable rates. So all I will have to do is glue them together.
For speaker wire I am looking at diy cat5 cables.
I am planning on a 7.2 system. For the receiver I am looking at the Yamaha Aventage.
For subs I am looking at the Rythmik servo CI 15" sealed. I am hoping they will not always be needed.
I am looking to use a acoustically transparent screen with a projector. It will be at least a year until it is built so I haven't picked one out yet. That technology seems to change rapidly.
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IMO you need to look at the 10.3P's maximum spl and check that it'll be high enough for HT use.
Provided you cross them high enough, the limiting factor will be the driver's power handling capacity.
If you cross them lower, then excursion could become the bottleneck.
Take these into consideration before you commit.
Good Luck!
Provided you cross them high enough, the limiting factor will be the driver's power handling capacity.
If you cross them lower, then excursion could become the bottleneck.
Take these into consideration before you commit.
Good Luck!
Sounds like a great project. I use a pair of A7.3s in my semi-dedicated home theater with great results.
As Hajj pointed out, you will need to pay special attention to crossover frequencies. I find that for music, my A7s are fine with a 100hz crossover point. For movies, I push it up to 150 - 200 hz. With a pair of good quality subs, higher crossover points may not be such an issue if the subs are positioned correctly.
That being said, the A10's can provide substantially more output than the a7s, and this may be less of an issue.
Good luck
As Hajj pointed out, you will need to pay special attention to crossover frequencies. I find that for music, my A7s are fine with a 100hz crossover point. For movies, I push it up to 150 - 200 hz. With a pair of good quality subs, higher crossover points may not be such an issue if the subs are positioned correctly.
That being said, the A10's can provide substantially more output than the a7s, and this may be less of an issue.
Good luck
Should sound excellent. I am not real familiar with the Yamaha. The key is to make sure it has adjustable crossover points for each speaker output or at least has some means to limit the low frequency output. I'm using CHR70.3 x 9 in my home theater and they work really well. My onkyo allows me to set the crossover for each speaker: 100hz to 120hz for 7 of them and the center about 80 hz. Subs are set at 120. My room is similar in size and configuration with slightly higher ceilings.
You are planning a very cool setup. Enjoy.
AK
You are planning a very cool setup. Enjoy.
AK
As you have selected should work pretty darn good and of course should you get over enthusiastic on the volume knob it's nice to know the "arrestor" is designed into the 10p to prevent killing one. You might explore more of what Rythmik has to offer as I understand that you can run up to 3 of the 16 ohm drivers off of one of the servo amps which would open up some nice possibilities for multi sub placements. Add to that the fact that the 10p's work well in multiple cabinet configurations, bass reflex, MLTL, Pencils, FHXL, and all I can say is - I wish I was having as much fun as you're going to!
The arrestor only takes care of the excursion.
A driver crossed high can still be killed by too much power, but this death is silent since the arrestor will never kick in and the user will thus never hear the distortion. Only a puff of smoke and then silence....
Just my 2 cents.
Actually braided cat5 pulling the white wire to one polarity and the colored wires to the other can work fantastic, especially if doubling, tripling, and quadrupaling. I am using just this way in one system and it works beautifully. And I also have several other speaker cable options on hand including some at $1200 for an 8ft pair. Read up on cat5 diy cables and hear for yourself.
myhrrhleine:
Dozens of us have been happily using CAT5 cable for well over a decade in a wide range of single and multi-way speakers with no ill effects. I do myself, but don't get evangelical about wire type - there are far more pressing concerns in designing an audio system - particularly when trying to digest the wealth of helpful advice on the subject to be harvested on fora such as these.
hajj
I doubt very much that the death of an A10P (or almost any driver) overdriven by musical signal would be completely "silent" - even if accidentally served an unheathly amount of DC from an shorted out power supply rail of a direct coupled SS amp there'd be an initial (perhaps very loud) thump, followed of course by a pretty little orange glow as the voice coil turns into a small electric heater.
how exactly do I know that?
Dozens of us have been happily using CAT5 cable for well over a decade in a wide range of single and multi-way speakers with no ill effects. I do myself, but don't get evangelical about wire type - there are far more pressing concerns in designing an audio system - particularly when trying to digest the wealth of helpful advice on the subject to be harvested on fora such as these.
hajj
I doubt very much that the death of an A10P (or almost any driver) overdriven by musical signal would be completely "silent" - even if accidentally served an unheathly amount of DC from an shorted out power supply rail of a direct coupled SS amp there'd be an initial (perhaps very loud) thump, followed of course by a pretty little orange glow as the voice coil turns into a small electric heater.
how exactly do I know that?
I am not worried too much about spl. 80db should be loud enough.
I am hoping to cross over at 60-80 hz if possible. Is that too low for this setup? How far from the listining position do I have to be to cross them that low? I was hoping aprox 10-15'.
If there is a better 7.2 receiver out there in the 6-800$ range I am open to other options. I am just going off of reviews on the aventage.
I am not going to be using single strand cat5 I'll use as many strands as needed.
Two Rythmik subs is all I can swing now. I think they will be enough. If I need more I guess I can add them later. I am planning on running extra wire locations for the subs so placement in the finished room will be easy. At least cat 5 is cheap. Also it dosen't have to be thick for signal wire.
I am hoping to cross over at 60-80 hz if possible. Is that too low for this setup? How far from the listining position do I have to be to cross them that low? I was hoping aprox 10-15'.
If there is a better 7.2 receiver out there in the 6-800$ range I am open to other options. I am just going off of reviews on the aventage.
I am not going to be using single strand cat5 I'll use as many strands as needed.
Two Rythmik subs is all I can swing now. I think they will be enough. If I need more I guess I can add them later. I am planning on running extra wire locations for the subs so placement in the finished room will be easy. At least cat 5 is cheap. Also it dosen't have to be thick for signal wire.
If the series R is sufficient anyway -depends on loop length.
Not necessarily an issue providing you account for it, & also somewhat dependent on amplifier output impedance since the higher this is, the less impact the wire R has. For the sake of interest, there was a brief fad back around the turn of the century for using single strands of 30ga magnet wire in HE systems (95dB or higher).
Not necessarily an issue providing you account for it, & also somewhat dependent on amplifier output impedance since the higher this is, the less impact the wire R has. For the sake of interest, there was a brief fad back around the turn of the century for using single strands of 30ga magnet wire in HE systems (95dB or higher).
CAT5 has significant capacitance between the conductors, which can be bad for amp stability if you have long cable runs. If you insist on using CAT5, then it would be better to use two CAT5 runs, each acting as a single core.
Simple figure-8 speaker cable is pretty cheap in 100m rolls so just use that. Even the skinny stuff has as much copper as a single CAT5 cable.
Simple figure-8 speaker cable is pretty cheap in 100m rolls so just use that. Even the skinny stuff has as much copper as a single CAT5 cable.
If you're still talking 10P (the .3 is metal cone version), in any but a woefully undersized sealed box, I'd imagine with would develop more than adequate LF response to allow for XO as low as 80.
I've built the MarKen for the 10.2. but not yet seen drawings for the .3 or P - so far the only enclosures into which I've put the 10P have been the FHXL and a small BR design ( by Eric Hartmann ?). Embarrassingly enough, after my first audition of the latter, I found that they might have been wired out of phase (see what happens when you're in a rush?), so they need a revisit, hopefully later tonight.
Without reigniting the perennial "wire" debate and all the subset arguments, yes cheap hardware store 18gauge (or less, gadzooks
) can work perfectly fine.
As to CAT5 - once Dave gets his power back on at home he might be able to answer this - didn't Aaron Drabbit publish some tests on this subject well over a decade ago when some of the local DIYers here started using it?
In any case, as I said before, I've been using it for at least that long, but admittedly never in lengths longer than 20ft, and have yet find an amp that had issues with anything from single strand per pole to the elaborate braided snakes of Chris Van Haus. Those are fine if you don't mind blisters and have a proper stripper.
How much capacitance would be considered "acceptable", and for that matter who much would "normal" speaker wire posses?
Anyone remember Polk Audio Cobra Cable? - now that stuff was "affectionately" nicknamed amp killer
I've built the MarKen for the 10.2. but not yet seen drawings for the .3 or P - so far the only enclosures into which I've put the 10P have been the FHXL and a small BR design ( by Eric Hartmann ?). Embarrassingly enough, after my first audition of the latter, I found that they might have been wired out of phase (see what happens when you're in a rush?), so they need a revisit, hopefully later tonight.
Without reigniting the perennial "wire" debate and all the subset arguments, yes cheap hardware store 18gauge (or less, gadzooks
) can work perfectly fine. As to CAT5 - once Dave gets his power back on at home he might be able to answer this - didn't Aaron Drabbit publish some tests on this subject well over a decade ago when some of the local DIYers here started using it?
In any case, as I said before, I've been using it for at least that long, but admittedly never in lengths longer than 20ft, and have yet find an amp that had issues with anything from single strand per pole to the elaborate braided snakes of Chris Van Haus. Those are fine if you don't mind blisters and have a proper stripper.
How much capacitance would be considered "acceptable", and for that matter who much would "normal" speaker wire posses?
Anyone remember Polk Audio Cobra Cable? - now that stuff was "affectionately" nicknamed amp killer
In terms of capacitance, what is acceptable depends on the amplifier. Some are unconditionally stable, some are... not anything like that.
CAT5 is specified as 55pF/m within a single pair, plus (my guess) about half that in inter-pair capacitance. If you split your signal amongst the 4 pairs, you're looking at 220pF/m or 4.4nF for a 20m run. CAT5 is 0.2mm^2 per conductor, or 0.8mm^2 = 18AWG if used as a single cable (a bundle of 4 each way).
Copper resistivity is 1.7e-8 ohm-m, which makes the (two-way, a bundle of 4 cores each way) resistance of CAT5 0.0425 ohms/m. On a 20m run (0.85 ohms), your cable will be eating 10% of your amplifier power with an 8R load, or 18% with a 4R load. Same with 18AWG but without the 4.4nF in parallel. And then go see what that does to your damping factor.
If you must use CAT5, at least don't split individual pairs. Use two colours (green+blue+striped) for negative and the other two colours (brown+yellow+striped) for positive, and that will reduce your capacitance greatly.
CAT5 is specified as 55pF/m within a single pair, plus (my guess) about half that in inter-pair capacitance. If you split your signal amongst the 4 pairs, you're looking at 220pF/m or 4.4nF for a 20m run. CAT5 is 0.2mm^2 per conductor, or 0.8mm^2 = 18AWG if used as a single cable (a bundle of 4 each way).
Copper resistivity is 1.7e-8 ohm-m, which makes the (two-way, a bundle of 4 cores each way) resistance of CAT5 0.0425 ohms/m. On a 20m run (0.85 ohms), your cable will be eating 10% of your amplifier power with an 8R load, or 18% with a 4R load. Same with 18AWG but without the 4.4nF in parallel. And then go see what that does to your damping factor.
If you must use CAT5, at least don't split individual pairs. Use two colours (green+blue+striped) for negative and the other two colours (brown+yellow+striped) for positive, and that will reduce your capacitance greatly.
As I noted earlier, none of my speaker runs with CAT5 are more than 1/6th of the 20meters (65.6ft) that you postulate, which probably explains why I've not encountered any issue in those cases. I had to actually for a minute about just how long those runs were.
Of course, if one was to get hair-shirt about it, the tightly twisted conductors in each pair could be unraveled and separate by an inch or two into a ribbon with packing tape.
For runs as long as the 60ft, the hardware store 18 AWG is probably fine - the multiple runs of CAT5 that laplace suggests would certainly work, but it's a pain in the *** to untwist and strip 8 conductors per end of each cable - particularly if you don't have an accurately calibrated stripper - the stiff #24 of solid CAT5 is very easy to and break. For my own HT system, I used a roll of Home Depot #18 multi-strand - the way the room is laid out, the run to the furthest rear surround must be close to 50ft.
Of course, if one was to get hair-shirt about it, the tightly twisted conductors in each pair could be unraveled and separate by an inch or two into a ribbon with packing tape.
For runs as long as the 60ft, the hardware store 18 AWG is probably fine - the multiple runs of CAT5 that laplace suggests would certainly work, but it's a pain in the *** to untwist and strip 8 conductors per end of each cable - particularly if you don't have an accurately calibrated stripper - the stiff #24 of solid CAT5 is very easy to and break. For my own HT system, I used a roll of Home Depot #18 multi-strand - the way the room is laid out, the run to the furthest rear surround must be close to 50ft.
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