Best way to bi amp my QLS-1's?

[goat67]

Pretty much just what I have found, not twice the volume, overall a slight better sound, although I seems to me the power indicators don't show it working any less, but for now I see no real advantage to change over to horizontal. Are not each channel of the amps doing the same thing either way vertical or horizontal, because by not using the active crossover I am amplifying the full range of audio on all four channels. If I choose to use the active crossover in the future I will go in and disconnect the passive one.

If you go this route do not remove the Coil and caps from the Watkins circuit this is required for the phasing on the dual voice coils.

Furthermore I do not know how you could even begin to bypass the passive xover this speaker is a 4 or 5 way depending on how you look at the rear EMIT
So One channel for the woofer leave the passive components
First Issue what are you going to do about the mid bass coupler? Ok another channel or leave some passive components and drive with the mids
Now for the mids there are 6 8 ohm speakers here how would you wire these to get to 4 or 8 ohms total impedance?
Finally the EMITs 8 front 4 ohms this is easier you can go series parallel combinations to get to 4 or 8 ohms
Oh yea what about the rear firing EMIT?

So for me this is not a speaker I would choose to try and run without the passive Xover Infinity designed

Now my RS 4.5s could be converted to a three way active fairly easily.
I still would keep the passive components for the Watkins

 

[Kencat]

If you go this route do not remove the Coil and caps from the Watkins circuit this is required for the phasing on the dual voice coils.

I believe I pulled this link from a post here in AK somewhere, but it can't hurt to put it forward again. It's about the best description of how the Watkins works I've seen, and by the inventor himself - http://groups.google.com/group/rec....=en&q=woofer+group:rec.audio.*+author:watkins

It definitely reinforces what goat67 is saying about not messing with that circuitry attached to the Watkinses (what are two Watkins :scratch2: ), even though Infinity screwed it up per Mr. Watkins - ya, have a read!

So for me this is not a speaker I would choose to try and run without the passive Xover Infinity designed

But the crossover is splittable by design between the bass woofers and the rest of the circuit by removing the jumper between the two sets of binding posts, allowing for a bi-wire or bi-amp setup. (I added this for any one not familiar with the QLS line who may be reading)

Removing the rest of the crossover and trying to run totally active would be a very interesting technical exercise. Whether the sound could be improved ? we never will know unless it's done. If I win the lotto I'll try it out on the Q2's - you all know the odds of that happening :sigh:

 

[jimreeves]

I thought I had read somewhere that they were phase-aligned by the passive crossover. If indeed they are first-order filters it's beyond me to figure out how. Bypassing the passive xovers may create some other issues as well.

 

[Maxamillion]

I attempted bi-amping on my RSIIb's using Gilmore Raptor 500WPC monoblocks on the mids and highs and a Crown XLS802D (800WPC) on the woofers, through the passive crossover. It sounded much worse than just using the Gilmores full range with the jumpers. It literally sounded like I was listening to two different amps (go figure!). I quickly went back to the Raptors alone.

http://www.glacieraudio.com/new Gla.../Gilmore/Gilmore-amps.htm#Anchor-Raptor-11481

Since then I have removed the internal crossovers and built external x-overs for the RSIIb's and am waiting for new diaphragms for the EMIMs and EMITs (see the other thread here about that story...).

 

[cdfac]

as always, there are pluses and minuses for going fully active. with a speaker as complex as these, i think you're going to have a difficult time achieving a better synergy than the stock setup. all crossover points are first order (only inductors or capacitors determining things, unlike both with the second-order RS1b's), but if you've got the time and energy it can't really hurt to experiment.

 

[Augy]

as always, there are pluses and minuses for going fully active. with a speaker as complex as these, i think you're going to have a difficult time achieving a better synergy than the stock setup. all crossover points are first order (only inductors or capacitors determining things, unlike both with the second-order RS1b's), but if you've got the time and energy it can't really hurt to experiment.

I would agree with cdfac here....It would be very difficult to go completely active here with a 4 way speaker.....Keep the internal xover and use an active 2way xover to split the signal going the the amps hi and low in a horizontal biamp....Easy to hook up and try out...and take apart if you don't like the sound....

 

[Ken Boyd]

If you go this route do not remove the Coil and caps from the Watkins circuit this is required for the phasing on the dual voice coils.

Furthermore I do not know how you could even begin to bypass the passive xover this speaker is a 4 or 5 way depending on how you look at the rear EMIT
So One channel for the woofer leave the passive components
First Issue what are you going to do about the mid bass coupler? Ok another channel or leave some passive components and drive with the mids
Now for the mids there are 6 8 ohm speakers here how would you wire these to get to 4 or 8 ohms total impedance?
Finally the EMITs 8 front 4 ohms this is easier you can go series parallel combinations to get to 4 or 8 ohms
Oh yea what about the rear firing EMIT?

So for me this is not a speaker I would choose to try and run without the passive Xover Infinity designed

Now my RS 4.5s could be converted to a three way active fairly easily.
I still would keep the passive components for the Watkins

I think you made your case very well!

 

[Ken Boyd]

I would agree with cdfac here....It would be very difficult to go completely active here with a 4 way speaker.....Keep the internal xover and use an active 2way xover to split the signal going the the amps hi and low in a horizontal biamp....Easy to hook up and try out...and take apart if you don't like the sound....

I know how to do it without to much difficulty but I doubt their would be any inprovement to be honest. Four 2 channel amps, a pair of 2 way active crossovers, Run first amp channel A using the the first active crossover channel A set for 200 hz and below and just run it right to the low frequency input of the OEM terminal, diconnect the mid bass speaker. next channel b of the other amp picks up from the 200 hz to 600 hz for the mid base, their is only one speaker so you don't have to worry about inpedance. Next a channel for the mids. another channel of the second active crossover start the mid point and roll off at your high point. On the speakers just unplug all the wires from the passive crossover to the mids and highs then use one good size transformer for the mids run the output of your amp using a 70 volt output and wire the whole run series parallel, as long as you have an even amount of speakers if the speakers are 6 ohms the entire run will look 6 ohms at the end. Or you can take 6 small transformers and mount them on back of the inside of the speakers and just daisy chain the whole row and tap each speaker what ever wattage you want it to be. As long as you don't tap the transformers so that total output of the run is more than 80% of the total wattage of the amp no problem. Then do the same thing with another run for the highs and include the rear EMIT. Now doing this way all of the speakers (mids and highs will put out an equal level as far as db's. It really wouldn't be that hard you would just look at the speaker cabinet in the same way you would look at a bar or eating establishment. Rows of mids and highs and rows of subs all running off off higher voltage amps only at each speaker there is a stepdown transformer that you tap for what ever wattage you want. The speaker cabinet would just be a miniture building, nothing really differnet. As far as phase alignment you use the time delays on your active crossover to get a the correct phase alignment.

 

[Ken Boyd]

Or even easier, a Crown 8 channel amp, and a DBX processer.

 

[Ken Boyd]

Or even easier, a Crown 8 channel amp, and a DBX processer.

Here would be an example of a set up like I described, I think this is two crown 6 channel amps this paticular amp set up I installed I had 16 runs to pairs of speakers which is why I ran the homeruns to 4 ohm outputs, two 8 ohm speakers on each run which made each run come out to a 4 ohm run. Notice the DBX Digital processor, and an Ashly item in that rack was programable volume controller to a 8 zone remote volume control connected by a cat 5 cable.

 

[Kencat]

Ken,

What would be an approximate cost for all that equipment to do this? just for interest.

 

[Ken Boyd]

Well you could get a Crown eight channel amp for less than two thousand, much less used. I don't know what the DBX cost retail but dealer cost is about 500 dollars. Stepdown transformers cheap 25 bucks apeice. But you could get some Crown Com Tech 200 used off the net for a couple hunderd a piece. So four of them $800. I have 8 or 10 of the Com Tech 200 just setting in boxes, they have outputs for both 8 ohm or 70 volts. A friend of mine who I worked for just told me a few days ago he has over a dozen Com Tech 800 and 1600's and he just wants them out of his way and he would make me a real good deal probably two hundred an amp. Many times when a new business goes in, or they upgrade a sound system they ship us all new equipment and we dispose of the old stuff. Many times the old equipment is much better than the new system that we put in, we laugh as we load racks of Rane, Dbx, Crown amps, JBL speakers, only to what they call upgrade with stuff like QSC and less quality speakers.

The 1600 Crown amp is 875 watts @ 4 ohms very stable at low impedances.

The Crown amps also have PIP which is modular plug in boards programable some of which you can program just what frequency that you want to amplify. The DBX digital processors you use your lap top program in levels, imputs crossovers, time delays, you name it.

Heres a 8 channel Crown 200 watt per channel brand new A stock for 1700 BIN on ebay. Crown has a three year warrantee no questions asked.

http://cgi.ebay.com/Crown-CTS-8200-...emQQptZLH_DefaultDomain_0?hash=item2a0365cc61

You would need to find out what is kind of the even point on the speaker like maybe it would be best to have one amp 400 watts for the bass, one hundred for the mid bass pair and then 200 each for the mids and hi's because inorder to get all the drivers to sound balanced you would want to control the attenuators on the back of the amps to get all the levels of each driver to the point which sounds good than once set you simply control the master level with your preamp.

 

[Ken Boyd]

One thing I might add, I wouldn't claim that the Crown 8 channel amps are going to be as good as many of the top of the line amps but they would be much better than any average audio gear. They do have some very high quality line ups and they did make their Reference amps which I would say would be very high quality, and the ones I see sell still get a premium price

Mentioned in a quite a few post is the opinion of vertical bi-amping over horizontal bi-amping, I would be interested in hearing how horizontally bi-amping is going to sound any better than veritcally bi-amping, I don't see how it would make any difference other than the reason I stated that Infinity recommended. Hopefully the output of each channel of an amp is going to be pretty much independant of each other, other than a common power cord and power supply wouldn't it?

Oh I forgot to mention one thing, I recall reading one of the major reviews when the Infinity QLS-1's first came out, if I recall the amps that they used to review them with I think were a Crown preamp and either a D150 or D300 Crown amp.

 

[Kencat]

Hopefully the output of each channel of an amp is going to be pretty much independant of each other, other than a common power cord and power supply wouldn't it?

(1) In the case of monoblock amps - independent yes.

(2) In the case of dual mono amps - hope so - claim to be free of interference from each other and the same as monoblock.

(3)Dual channel/Shared power supply - crosstalk issues? If this was "ok", why the big hype on Dual-mono?????

So.....it could depend on what type of amplifier you have......case (3) favours the horizontal bi-amp with active crossover before amp scenario, my gut instinct says. Can't justify with any certified theory though.....any electronic engineers out there???

 

[bobrown14]

The pre-amp has two outputs but the parametric EQ only has one so in-order to use the EQ I have to use two splitters to provide input for two amps, and I don't have any good splitters, just junk from Radio Shack, all my interconnects are pretty good pure silver with really good connectors, don't know how much that matters but seems silly to have good expensive interconnects only to have them running thru a pair of cheap splitters.

This may have been covered as I'm not finished reading all the posts. Regarding your EQ - hook it up the the tape 1 loop and not from the pre -> eq ->amp. This is the way it's "supposed" to be done. Your setup works until you need a second amp. I've did the same as you until I hooked up my QLS-IIIs with 2 bridged mono amps Vertical bi-amp). I switched my EQ to tape 1 loop. You can then take the EQ out of the signal path with a flip of a switch. With the other setup you still have the EQ in the listening chain regardless if its on or not. With a new setup I'm messing with I usually do not listen with an EQ until I've got my system sounding the way I like it then I fine tune (if need be) with the EQ.

Regarding the active crossover used in combination with passive crossover. You're not going to get any if at all sonic improvement without changing
the passive crossover. I'm not familiar with the passive one on your speakers but some speakers I have have a passive crossover with different wire hookups (adjustable on the crossover) for bi-amp, tri-amp etc. Change a few wires (jumpers) and you can add amps. Still passive crossover in the chain so I would not expect too much improvement sonically with an active crossover without changing the passive crossover.

You can however increase your amps efficiency with an active crossover splitting the signal from the pre to the amp with the active crossover. pre -> active X-ver - Amp1 & Amp2 (and changing your passive crossover). Be sure to get some overlap and let the passive crossover in the speaker do it's thing. (horizontal Bi-amp).
Amp1 -> mids/highs, Amp2 -> Watkins. I'm suspecting this was your goal - give the Watkins just the low signal they need to make your amp more efficient. It will work but as mentioned the crossover point needs to be addressed for best sound. I've found the vertical bi-amp to work for me, full range to each speaker but wattage x2 the stereo output (in my case) in mono, since the amps are bridged. Somewhat better more clear sound and punch as I've got more horsepower to each speaker. Again this is with the QLS-III not your setup. QLS-IIIs don't have any settings for bi-amp, so this works best for me.

I've messed with this with other speakers and decided the extra active crossovers I was using were adding (actually taking away) too much from the sound, with regard to clarity. Could have been the crossovers but they were Rane... Just didn't give me much of anything worthwhile sound wise. Sometimes more = less, in my case I thought so. Please excuse me if some of this was covered. It's my experience with active crossovers.

To sum it up - the speakers I have that have jumpers for bi-amp, they sound better without any active crossover, full range and let the crossover do it's thing. I bet I could get it to work with the active crossover, but I think I need more equipment for testing purposes to be able to match/beat the crossover designers, oh and a lot of free time on my hands.

YMMV of course.

Cheers,

Bob

 

[Ken Boyd]

Recently I have changed the main speaker cables to the highs with a pair of 16 stranded pure silver cables and have given it some time and notice quite an inprovement. Much more detailed and clarity on the highs. I am still using copper leads on the Watkins drivers and have it vertically bi-amped using just the passive OEM crossover. The bass is great no problem with just my copper leads.

 

[Nikkoholic]

Just a comment. I have run my QLS1's with horizontal biamping and an active crossover with independent set points for upper and lower freq. So I can set the crossover point just a little beyond the passive to assure no loss of freq.

I also run Nikko 330w/ch (alpha 650) on both the hi freq and low freq. You will quickly find there is a limit to what the Watkins can handle. After long talks with Bill Watkins the speaker has a limit and will bottom out on the spider? (not sure if I'm using the proper terms, it was a talk 9 months ago). But point is these will not absorb infinite power. At 330w/ch using and using an active crossover it is all these speakers can take. I have comfortable headroom, but I have to watch the woofers on particular music selections with extraordinary bass.

The passive crossover for the remaining hi freq drivers has a lot of controls built into the speaker. Each driver group has its own level control and there is a crossover point selector to modify the crossover point. My comments are basic, but clean power somewhere around 200+w/ch x 2 and an active crossover is all you need. Not sure how that equates to cdfac's success with the 500/ch and no active crossover, but likely it's equivalent and likely the sound is too.

Good luck and interesting post.