Best way to tri-amp?

[tsmith1315]

kfr01:

I just want the best and most flexible (hopefully reasonably easy too) way to implement an active crossover system for a modest amount of money.

Well, the most economical way would probably be an analog DIY system. But at the risk of being tackled and beaten, a very economical AND easy way would be to follow Bill's advice and use an automotive system. You can pick them up on ebay for a song.

If the idea irks you, consider that any crossover for home or pro use would have a DC power supply inside anyway.

Here are a couple I found with a brief search:

Image Dynamics

This one has a pair of 3-way outputs, and a pair of 2-way outputs in one unit.

H/K

And one other, simpler option is the Harrison F-Mod. They have other unconventional solutions, and respond to email favorably...

Tim

[paulspencer]

I notice some assumptions coming up here that are not necessarily always true:

* home audio equipment is more hifi than car audio (probably true most of the time, but this is not automatically true of all car audio equipment)

* PA equipment isn't as hifi as home audio

* passive crossovers are more hifi than digital crossovers (I doubt this is true)

Many in the audio industry take advantage of assumptions and perceptions, and diyers are at a big advantage if we see through the myths and assumptions.

Originally posted by kfr01
The front 3 speakers will be tri-amped and the rears will be bi-amped. Is this possible? What is the easiest / best way to do this?

First get a powerful digital crossover. Ultradrive is a low cost unit that is much used and its easy to find mods as many have used it. A number of kit retailers recommend this unit, and I believe they offer support. Bamberg Labs (BESL ) and
Newform Research come to mind.

Newform also recommend a unit by an Australian company called Clarity Eq - DEQX (also has a preamp version). It is more expensive but you can buy reconditioned units which are cheaper and they include a digital crossover as well as room correction. Very sophisticated.

I suspect comments like "universal active crossovers should be ignored" may not apply to units like these. They are very powerful and have a range of filters that can be employed.

My suggestion:

1. get a digital active xo
2. use it to run your front speakers (1 unit)
3. use it to design analogue active filters for your remaining speakers

Originally posted by kfr01
I am a software guy. [/B]

Keep in mind that just because you have a skill and want to use it, doesn't mean this will be the easiest or most suitable path to take. Even with your skills in software it may still be easier/better to get a dedicated unit. For one thing I'm skeptical of sound cards, and do you want to have to turn your computer on just to listen to music? Or have fan noise during a movie in quiet scenes?

Don Mauer has done work on digital crossovers for a Phoenix system:


http://home.pacbell.net/donwm/

Originally posted by kfr01
I'm sure the quality isn't as great as home systems

That assumption might not help you ... have you considered trying out your car equipment for your home system? You just need a power supply. Let your ears tell you how good it sounds.

Originally posted by kfr01

But I would find it absolutely amazing if a universal active crossover combined with some amount of tweaking could never come close to the sound quality of a passive.

I'd expect better than passive.

[OMNIFEX]

Originally posted by kfr01
The front 3 speakers will be tri-amped and the rears will be bi-amped. Is this possible? What is the easiest / best way to do this?

Method 1
I would get two 4 way Stereo Analog Crossovers on Ebay.
Use each device 6 way mono, thus, making 6 way Stereo.

OR,

Method 2
Get one 3 way Stereo Analog Crossover, and, one 2 way
Stereo Analog Crossover. (Same Brands)

Y the output of your preamp, and, you'll have 3 way stereo
for your mains, and, 2 way stereo for your rears, with the
master control from your preamp.

You would only need a Y Adaptor, if your Preamp offers
only one set of preamp outputs.

Actually, you can by two Behringer Ultradrives, and, follow
method 2 if you want to go the digital route.


Complex Connections, I'm A Wiz At That!

[carlosfm]

Originally posted by kfr01
I don't think I like that answer.

You didn't understand my post.
I was telling you that or you have an active crossover for your speakers, or you DIY one.
I'm not so convinced about generic active crossovers.
And no, you can't have the same sound in a car that you can have in your room.
Sorry, but that's how it is.
A car doesn't have the phisical conditions like a room has.
Ultimately, on a car it seams that you are inside the speaker.

[PassFan]

I'm not sure it will help you any but a great source for active crossover components is http://www.marchandelec.com

They have many selectable and customizable x-over setups.Good luck

[bser]

Originally posted by OMNIFEX


Method 1
I would get two 4 way Stereo Analog Crossovers on Ebay.
Use each device 6 way mono, thus, making 6 way Stereo.

OR,

Method 2
Get one 3 way Stereo Analog Crossover, and, one 2 way
Stereo Analog Crossover. (Same Brands)

Y the output of your preamp, and, you'll have 3 way stereo
for your mains, and, 2 way stereo for your rears, with the
master control from your preamp.

You would only need a Y Adaptor, if your Preamp offers
only one set of preamp outputs.

Actually, you can by two Behringer Ultradrives, and, follow
method 2 if you want to go the digital route.


Complex Connections, I'm A Wiz At That!

Will any of these options work if the goal of the system is home theater with a 5.1 setup? Not saying you're wrong at all, just I don't understand how you are going to get 5 discrete channels from this method, please explain.

[OMNIFEX]

The poster mentioned Tri - Amping. So, he will need to
have muiltpile amplifiers to achieve Tri-Amping.

So, for his requirements:

Mains Tri-Amped

One Amplifier For The Lows

One Amplifier For The Mids

One Amplifier For The Highs

Rear Bi-Amped

One Amplifier For The Low/Mid

One Amplifier For The Mid/Highs


The processor (decoder) should give you a mains
out, and, a rears out. So.......

3 way Crossover for the Mains

2 way Crossover for the Rears

You use the processor (decoder) as the master to manipulate
the sound.


I'm guessing he didn't count the fifth channel, due to being
a subwoofer, and, he already has it covered.

[wigginjs]

I think the problem is there really aren't any digital crossovers/equalizers designed to be used in a 5.1/6.1 environment available for home/pro audio. Taking that car unit and using it with a DC supply is an interesting idea, but I think for around the same price you could get two Behringer Ultradrive 2496 units, use one for triamping the main speakers, and the other for biamping your center and two surrounds. This bumps you up into the $800 range, and for the other $200 you could buy a nice reciever to do your decoding of DD/DTS and input switching. This is the only solution I know of that comes close to doing what you want.

----
Edit
----

My response was assuming that a digital active crossover with EQ was required, this can be more painless is you are willing to go with an analog active crossover. Get three Behringer CX3400's and you'd have the ability to 3-way active cross 6 speakers. 3 of these run ~$400, approximately half of what 2 Ultradrives cost. Same story with the reciever to decode, except you can do it this way for about $600 instead of $1000.

Sub-note and you can take this how you wish:
Active crossing your main speakers would be highly recommended, active crossing your center channel would be nice, and active crossing the surround channels would be (IMHO) a large amount of extra effort for low return. Any time I've done something to upgrade my surround channels I've always been a bit disappointed, I just don't think you notice additionaly clairity very much in those channels. Anyway, just my opinion.

[paulspencer]

Originally posted by m0tion
I think the problem is there really aren't any digital crossovers/equalizers designed to be used in a 5.1/6.1 environment available for home/pro audio.

Actually there is. Audio Control Diva, but it's quite expensive. It's under the technical section of their website, and there are two reviews linked.

I think Behringer units look more powerful and cost effective, however.

You may wish to look for HT receivers which have pre-outs AND main in connections. Pre out is an output from the preamp. Main in is a line level source to the power amp for each channel. You have to spend a bit more to get this feature, but it means that you can use eq and active crossovers in between the pre and power amps as well as still use the existing power amps of the receiver. This will help keep costs down. Suppose you wanted to take some load of the power amps in the receiver you could use them for the tweeters, which don't require much power. Alternatively, you could use them for the midbass, then build low power chip amps for the tweeters.

[wigginjs]

Preouts are definately a must. I don't know of any recievers with main-inputs, but this would certainly be a great feature to have. I've got a feeling it would bump your price up significantly. I've been using a Yamaha RX-V650 for my preamp and I've got to say I really like it. It can be had for around $300 (maybe $250?). Great unit. Behringer is about as cheap as it gets (price-wise) for pro-audio tools like active crossovers and equalizers and I've heard they are of decent quality too, so I'd check them out first for your processing needs.

As for amplification, this seems perfect for a multi-channel LM3875 (or similar) amp, but thats another DIY project in itself. Whatever solution you find, I'd be interested to know the results.