Page 2 of 2

Re: Bi, tri amping (multi-speaker system)

PostPosted: Sat Jun 14, 2008 12:18 pm
by edrel sison
lovejbl wrote:Audiostar, hindi ka nagiisa ako baliw na baliw. My system is in the works but completion is in the horizon, they are the following:
1) DIY pre-amp 7193s
2) DIY electronic 6-way crossover
3) DIY 12 tube amps 12ax7s, kt88s single ended and push-pulls
4) all jbl components 2404, 2426, 2450, le 10, 123a-1, le 14, prc15

lovejbl :roll:


wow, you really love JBL. i have a feeling you are from malabon too or quite near the the area :D :D ...

Re: Bi, tri amping (multi-speaker system)

PostPosted: Sun Jun 15, 2008 6:40 am
by egay
edrel sison wrote:
lovejbl wrote:Audiostar, hindi ka nagiisa ako baliw na baliw. My system is in the works but completion is in the horizon, they are the following:
1) DIY pre-amp 7193s
2) DIY electronic 6-way crossover
3) DIY 12 tube amps 12ax7s, kt88s single ended and push-pulls
4) all jbl components 2404, 2426, 2450, le 10, 123a-1, le 14, prc15

lovejbl :roll:


wow, you really love JBL. i have a feeling you are from malabon too or quite near the the area :D :D ...


lunasol siguro :lol2:

PostPosted: Sun Jun 15, 2008 6:54 am
by egay
i noticed that many of my european friends find multi-amping simply "regular" and nothing to talk about :-|... i mean, it is a common fare with them that if you're not multi-amped, 'you came from somewhere else :oops:

i think multi-amping a SINGLE BOX SPEAKER (at least bi-amp) is questionable in the benefit department, but i am not against the practice - "if you have it, then use it" - i would say... but to harp about benefits is rather suspicious to me. of course that's me.

as i see it, multi-amping only benefits large and hard-to-drive speakers; and going the ACTIVE route is one way to go - the other is DESIGN or MAKE each amplifier "fit" the crossover of each speaker section (i apologize for NOT knowing the right terms).

now, for large, individual sections (like how they do it in Malabon), multi-amping is "a natural choice": first, because they can; 2nd, because they can... dami atang na-ipon na tubo galing pa ng gyera...

but it's funny (in a nice way) & intriguing: my friends multi-amp their EPOS, KEF, other EU models like its simply breakfast for them :D

Greets!
.e.

PostPosted: Sun Jun 15, 2008 8:50 am
by alvinthx
JackD201 wrote:
alvinthx wrote:The problem with having a bi or tri-amp system is how to match the level of the amps driving the speaker system as well as the selection of crossover points. Without specialized equipment (RTA, SPL meter), it would be a trial and error just to adjust such levels.

Amps as well as drivers like to be band limited therefore, I welcome multi-amping if you have access to such equipment and know how to use them.


Using waterfalls and FFTs is always recommended to get the system as flat as possible at the start however final tuning by ear is always the last step by FOH engineers. That's why the good ones get paid more. This is even more true of home systems as some people do prefer to have some dips, humps or even knees and shelving. The good thing about real time analysis is that after tuning by ear you'll actually see what your preferences are and this makes the process both enlightening and more importantly REPEATABLE. ;)


That's true, but using instruments will put you within acceptable tollerances. Tuning by ear is at best adjusting by a few dB. A flat response sounds terrible. The key is to know your target curve for a particular venue. A venue with 350 seats up will have a very different curve from that below this figure. Even a regular size living room has a different Target and RT60 Curve.

I tend to believe that ALL respected speaker manufacturers have high grade test equipment at hand.

What I am saying is, venturing into Bi, tri or even Quad-amping is more complicated than it looks.

I use Waterfall with a 4-input Microphone multiplexer with Lab grade microphones for my analysis. This is the best way to see in REAL TIME any changes made for ALL seats. :P

PostPosted: Sun Jun 15, 2008 9:26 am
by JackD201
alvinthx wrote:What I am saying is, venturing into Bi, tri or even Quad-amping is more complicated than it looks.


It adds some intermediary steps but nothing someone with the desire to experimant and learn can't hurdle. I did it as a 16 year old without any test equipment.

The experience of setting up active x-over rigs in places as diverse as homes, ballrooms and gyms however stayed with me. Don't get me wrong, I'm all for measurements. I'm a certified recording as well as a multi-channel post engineer, albeit non-practicing. I'm also certified for design and construction of critical listening environments. Because of this I do recognize that tuning a room requires you go heavy on measurements but making the recording sing requires some artistic license.

The reason for going active for pro purposes is very different from those that do it for home enjoyment. On the road it's a matter of efficiency and modular make-up for quick troubleshooting. Time is money. For home use it is for specific voicing combinations between amp and drivers and the money part revolves around how much you want to spend and not how much you stand to earn. Also as far as musical content is concerned having the system sound good from all seats is not as important as getting that one seat right unlike with movies where you'd like the whole family to enjoy.

PostPosted: Sun Jun 15, 2008 11:06 am
by amandarae
Uy, sama ko dito!

Linkwitz Orion Plus. Dipole active 3 way, 4 channel at 60wpc per channel per speakers. Total 8 for the speaker pair. Active Signal Processo (ASP) after preamp with adjustable gain on dipole tweeters and dipole woofers with the mids as reference.

These are the specifications:

Open baffle cabinet
Outside dimensions: Height 46.25" - Width 13"
Depth 2" at top, 12" at base, 16" at 14" up
Weight 60 lb (27 kg)
3-way active speaker system
Crossovers at 120 Hz and 1440 Hz, both LR4 (24 dB/oct)
Crossover/Equalizer using two ORION ASP printed circuit boards
Tweeter - Seas T25CF002 - No, not a ribbon -
42" up, no 2.8 kHz notch filter as in PHOENIX
Preferably no grill to cover the tweeter
Midrange - Seas W22EX001 - No, not a smaller diameter -
Front mounted to baffle, no spine, but see Revision 0.1
34.5" up, 5 kHz notch filter
Woofer - two Peerless 10" XLS, 830452
Push-pull mounted in H-frame of 11.5" x 11.5" x 24.5" OD
Each driver with its own >60 W amplifier
Response -3 dB at 30 Hz (-6 dB at 20 Hz for Q = 0.5 and -12 dB/oct to 5 Hz)
Eight power amplifiers (e.g. ATI model AT6012)

More info on the the links below

http://www.linkwitzlab.com/orion++.htm


http://www.linkwitzlab.com/orion_us_examples.htm


Pwede!!!

regards,

Abe

PostPosted: Mon Jun 16, 2008 11:57 am
by audiostar
Alvin, thanks for your inputs. I wish you could bring your measuring device when you come for a visit to listen to my humble set up. I want some confirmation if my ears match the tech config :) I'm planning a Pampanga trip 2nd wk of July. Just confirming your invitation: I can pay you a visit by then :)

PostPosted: Thu Jun 19, 2008 12:57 pm
by alvinthx
No problem Val, I'm looking forward to your visit. (Comeby with Mr. Gomez)

Re: Bi, tri amping (multi-speaker system)

PostPosted: Fri May 08, 2009 8:59 am
by Quiel
any comments on http://www.behringer.com/EN/Products/DCX2496.aspx for those who took this path in their audio journey?

came across this product while day-dreaming on a multi-speaker stereo system.