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TLA Pro amplifier selection- Bi-amping with DSP

Posted: Tue Nov 14, 2017 11:34 pm
by Keryn O'Shea
Ok so, planning to build a pair of rectangular TLA Pros soon, 8x8 inch mids and 8xGT-1016 tweeters each for indoor work.
As I want to bi-amp with DSP, the question is, how much grunt do I need for mid and high on each channel? Will be using with 4xT30's LAB12 loaded, 80-100Hz x-over. I can source stand alone D-class amps with 15w-2500w ratings and external power sources (48V DC), so spoiled for choice there.

Let's assume I'm using the Eminence Alpha 8 mid.

Would the GT-1016's play happily at a 3.5kHz x-over point?

I'm thinking the tweeters wouldn't need more than 75-100w per channel, but the mids I'm only guessing at 600-800w per channel would be enough.

I'm not changing my mind about bi-amping!

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Wed Nov 15, 2017 12:11 am
by Grant Bunter
Keryn O'Shea wrote:Ok so, planning to build a pair of rectangular TLA Pros soon, 8x8 inch mids and 8xGT-1016 tweeters each for indoor work.
As I want to bi-amp with DSP, the question is, how much grunt do I need for mid and high on each channel? Will be using with 4xT30's LAB12 loaded, 80-100Hz x-over. I can source stand alone D-class amps with 15w-2500w ratings and external power sources (48V DC), so spoiled for choice there.

Let's assume I'm using the Eminence Alpha 8 mid.

Would the GT-1016's play happily at a 3.5kHz x-over point?

I'm thinking the tweeters wouldn't need more than 75-100w per channel, but the mids I'm only guessing at 600-800w per channel would be enough.

I'm not changing my mind about bi-amping!
G'day Keryn,
Nice to see you dropping in mate!
Are you happy with 4 ohms per cab? Nine x 8 ohm mids/cab would be 8 ohms (or 8 x 4ohms).

What version of series/parallel wiring you end up doing will determine if 6-800W is enough (add some heardoom), but sounds like a good starting point. No doubt distortion will let you know if you're to loud anyway.

Are you planning to chop down the 1016's?
3.5K is fine for the 1016's. Make it the corner frequency with a 12dB filter, as you would find in the plans for a passive crossover. 50-100W should be heaps...

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Wed Nov 15, 2017 8:01 am
by Bill Fitzmaurice
There is nothing to be gained bi-amping piezos. Bi-amping is useful when your HF section draws enough current to put a sizeable load on the amp. Because they are a high impedance load piezos draw practically no current.

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Wed Nov 15, 2017 4:41 pm
by Keryn O'Shea
G'day Grant, cheers man!
Yes, wiring at 4ohm, and cutting down the peizo's. Thanks for the confirm on filter values.

Hi Bill, understood on the info regarding tweeters, thank you. I just really enjoy the flexibility of running 3-way after playing with your HT designs, and already having the DSP, the amps are available to me for a few dollars more than building a filter here in Aus after Jaycar discontinued their stock of filter components which were affordable. The next best is Jantzen which are great but double the price!

Check out "Sure-hifi", a seller on Ebay, I've been using their DIY Amps systems for 3 years and they work really well, at surprising prices. Start with "d-class amp" search.

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Tue Apr 10, 2018 7:55 pm
by Keryn O'Shea
Buying the amps.. no problem, but pricing up to make the power sources has made it not worth effort going that way for these cabs. I've found two QSC 3000s for $220ea, came from a permanent install, plenty of grunt, and I forgot how nice it was to have an actual EQ you touch with your fingers!, guess I'll be saving digital three way happiness for HT.

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Sun Apr 22, 2018 4:34 pm
by Keryn O'Shea
After mocking up the cab, I found them super heavy, and with the pole mount centered it doesn't want to sit happily on the stand. So I found moving the pole mount to 10mm to the inside of the woofer centreline, the cab is resting nicely.
I'd use 3/4 ply for the baffle next time as the 1/2 felt a bit flimsy, so beefed up the bracing and pole mount.
20180422_150549.jpg

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Sat Jul 28, 2018 4:23 pm
by Keryn O'Shea
Finally had time to set these up outside and give them some juice for the afternoon, with a pair of dual 18 cabs which just kept up. The sound is Amazing, even 100m away down the paddock, the sound was full, smooth and tasty!

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Sat Jul 28, 2018 11:18 pm
by Tom Smit
:clap:

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Sun Jul 29, 2018 10:15 am
by SethRocksYou
Cool build. Congrats on completion. Thumbs up

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Sun Jul 29, 2018 2:54 pm
by Grant Bunter
Nice work as always Keryn!

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Mon Jul 30, 2018 4:00 am
by bitSmasher
They look mean! :!:
Keryn O'Shea wrote:
Sun Apr 22, 2018 4:34 pm
I found them super heavy
How heavy is "super heavy"?

Re: TLA Pro amplifier selection- Bi-amping with DSP

Posted: Mon Jul 30, 2018 5:28 pm
by Keryn O'Shea
Thank you all for the kind words! The weight came to 46kg each, doesn't really sound heavy, but maybe they're just awkward for me to move around and fit on the stand.
I'll be flying these in my shed for music (and for storage), and to see if I can get away without subs for the everyday tunes. Hoping the brackets are strong enough, what do you reckon?
I didn't fill the countersunk brace screw heads to see what it looked like under paint, and with a large surface area, one scratch instantly draws your eye. I'll see how that theory stands up over time as they wear.
I Had to cut 4-5kHz 12dB to sound nice to me, is that just the 8" drivers?