4 replies to this topic

[jrad]

Howdy,
I want to setup and active system with equipments and specifications as below:

HU: Alpine 9887 (in 3-way mode)
1) Front: Hertz HSK 165 (Woofer: 100Wrms, Tweeter: 120 Wpeak): 125Wrms with its passive xover
2) Rear: Hertz HSK 130 (Woofer: 90Wrms, Tweeter: 120Wpeak): 100Wrms with its passive xover
3) Amp: Hertz HDP4(D-class 1000w): 4*150Wrms @4ohm (4*250Wrsm @2ohm)
4) Sub: Hertz EBX-200: 250Wrms (500Wpeak)
5) Sub-Amp: Hertz HE1D(900W): 1*200Wrms

My question is about bi-amping and the finest SQ-oriented design alternatives!
First proper solution is to connect each woofer/tweeter pair in parallel with my HDP4 in each of these ways:

1)
Channel 1: Right front+rear tweeters in parallel
Channel 2: Left front+rear tweeters in parallel
Channel 3: Right front+rear woofers in parallel
Channel 4: Left front+rear woofers in parallel

OR

2)
Channel 1: Right+Left front tweeters in parallel
Channel 2: Right+Left rear tweeters in parallel
Channel 3: Right+Left front 16.5" woofers in parallel
Channel 4: Right+Left rear 13" woofers in parallel

But I think I'm wasting power for my tweeters! so I could use those 4 channels to drive 4 woofers!
And change my HE1D Mono to HE4.1:
HE4(800W): 2*100Wrms @2ohm + 1*200Wrms @4ohm

To drive 4 tweeters with 2 channels in parallel and bridge the other 2, to drive my sub! In this third method I guess sub would be under-powered! and also tweeters may not sound as good/nice/aligned to/with my woofers!

I like nice, clear, flat, real sound with a normal quality, soft sub sound (no vibrations,...) and I was driving same speakers with a EP5 AMP (which I sold) in passive mode for two years:
EP5 (630W): 4*60Wrms @4ohms + 1*160Wrms @4ohm

Any suggestions/help/experiences?

Edited by jrad, 28 December 2011 - 12:15 AM.

[Damon]

Well, first of all, option 2 is completely out becuase that would arrive at mono! Paralleling the left and right speakers does that.

The first option is less than ideal since much of the benefit of active is independant channel time correction and the ability to vary the crossovers for each speaker individually. With Option 1 you have front and rear speakers paralleled so therefore you cannot control either time correction nor channel intensity (loudness) individually. Furthermore, having 6.5 and 5.25-inch midrange drivers paralleled forces you to use a HP filter to suit the 5.25-inch whereas the 6.5-inch will play significantly lower.

So, neither way is very good, while Option 2 is an absolute no no.

Therefore you need Option 3.

Focus on tuning the front stage only and ignore the rear. Since the Alpine IMPRINT system does not offer HP/BP/LP plus a full range output for rear speakers I suggest running the system this way:

1: Set crossovers to 3-way with tweeter/midrange/subwoofer
2: Connect just the front tweeters to channels 1 & 2 when fed by the tweeter outputs of the source
3: Connect the front midrange speakers to channels 3 & 4 when fed by the midrange outputs of the source
4: Wire the passive crossover for the front set in line with the front midrange drivers to apply a LP filter
5: Set the LP of the midrange output of the source to FLAT
6: Connect the rear speakers to another amplifier while being fed by the same midrange outputs as the fronts via RCA splitters, thereby setting their own independant level.
7: Now set the front crossover points and time correction as required.

[D34M0N.inc]

What damo said

[blabla]

How did the hertz he1d go?? Looking at getting one but ye ppl are saying its under powered for my sub.

Edited by blabla, 31 January 2012 - 12:35 AM.

[muzzy66]

Hmm..I'd just run the front stage active and then run the rears passively off the factory crossover personally. I don't see much point in running rears active at all to be hoenst, especially fi they are going to be attenuated to be signficiantly quieter then the fronts.