QLS-1: Balance of Power?

[Ken Boyd]

I am interested in the opinions of other QLS-1 owners in what ratio of power between the Watkins and the hi frequency drivers when bi amping your Infinity QLS-1's.

I am thinking unlike some of my other Infinity's when bi amping these Quantums might sound better with more power to the hi frequency drivers than just using equal power. On my RS-1's I have found that to be the opposite as I usually use an amp about twice the power for the base towers over that of the upper end towers. But I am thinking and help me out to see if I am wrong here, that the QLS-1's need more power for all them mids and EMIT's to get a good upper end balance over the bass from the Watkins. The amps I am currrently using I don't have the ablity to adjust the gain on the bass drivers amp, only the hi end amp, and I had it cranked all the way up and I felt that the mids and hi's were just not cutting it. I don't find that problem on the QLS-2's of mine and I think it has to do with having much less mids and hi drivers that its allowing for more mids and hi frequencys to be heard as I am losing less due to the amount of power that it takes to drive all those drivers in the QLS-1's.

Have all you owners that bi amp yours use equal power amps for both ranges or do you use your gains to equalize them, and what have you found to be a good balance as far as power for each range to work well.

Right now they are down, and I am using one of the pairs of QLS-2's that I own, and this pair doesn't have dual sets of binders for bi-amping and I find them to sound much better than the QLS-1's on the mids and hi end, just much more foward and not so subtle on the hi's.

Edit: I might find that the problem lies in the caps and pots, and I am currently working on them. But I still am interested in everyones opinion what they have found to be the best.

 

[tubed]

Wow, Just in the past couple of days, I've pondered this same question of balance.
However I wondered what it would be like to supply more power to the low frequencies than the top end
I've been listening to my QLS-1's vertically biamped by way of two Yamaha M-85's.
The M-85 has left/right gain controls.
One amp per side. Left channel powering the lows, the right channel the highs on the left speaker. Right channel powering the lows, left channel the highs on the right speaker.
I leave the gains powering the lows at full gain and am currently adjusting between 12 o'clock and 1 o'clock gain position for the highs.

Interestingly I did not notice a huge unbalancing of lows vs. highs, but tighter deeper bass response and the best effect is the mid bass coupler comes alive with he added power.
I really like this setup as the QLS-1's have never sounded better.

 

[Ken Boyd]

I am using two different amps on my set up so I couldn't vertically bi amp them. But I have another pair of QLS-2's that I am vertically bi-amping and they sound very balanced using both amps set at equal gain.

Both the QLS-1's and QLS-2's use the same Watkins driver, but where the difference is look at how many more mids and hi's the QLS-1's use, and they are the same drivers as well, only a lot more of them, so it would seem to me that having a bit more power would be needed to get them to balance out with the bass driver. I would think that with more drivers the don't have to work as hard so lower distortion is a benifet but having an equal power to one set of drivers that has only one third the number of drivers have more output than the same amount of power with triple the drivers? Just seems with all those drivers you gonna have some lose in output unless you increase the power.

I guess what I am trying to understand is if you have a couple of drivers driven by an amp and they put out x amount of SPL, then take the same amp triple the drivers, would you have an equal level of SPL as the other one, or is there some loss due to the increased amount of speakers? I would think that the one with all the drivers should have the capablities of higher ouptut levels than the lessor amount of drivers and less distortion since the don't have to work as hard, but I would think some where you going to loss some efficency with the increased amount of drivers and would need to increase the current to keep the same SPL level.

 

[tomlinmgt]

FWIW, the guy I bought my QLS-1's from had -2's also. I listened to them side by side and never once thought the -2's had more of anything to offer than the -1's. I suggest you get your -1's restored and operating properly before you draw any conclusions, Ken.

But I am interested in hearing how it would pan out if you did what you're considering.

 

[tubed]

I guess what I am trying to understand is if you have a couple of drivers driven by an amp and they put out x amount of SPL, then take the same amp triple the drivers, would you have an equal level of SPL as the other one, or is there some loss due to the increased amount of speakers? I would think that the one with all the drivers should have the capablities of higher ouptut levels than the lessor amount of drivers and less distortion since the don't have to work as hard, but I would think some where you going to loss some efficency with the increased amount of drivers and would need to increase the current to keep the same SPL level.

My recently recapped Q2's have always seemed to suck up the juice.
I wouldn't be surprised that the QLS-1 puts out quite a bit more SPLs at the same power input as the Q2's. I don't have measuring equipment but sounds like it could be the case.

 

[Ken Boyd]

Well you guys can help me out here, lets just forgot about the lower range, and focus on the upper end, which is more efficent and would put out more SPL with one watt of power, the top end of the QLS-1's or the QLS-2's? I am thinking the small ones with less drivers are going to be more efficent and produce more db's for an equal amount of power.

 

[SicMan]

The QLS1's present a wider load to the input and the sound is spread out over the whole array of speakers.
I can't compare but the BETA's I have just blow away the sound of my Q's with 8 - 12" woofers and the array of mids these are so much better sounding to me anyway over all the QLS series speakers I've heard. Of course they are a bit more pricey ... LOL !!! and everybody hears the music different.
I've noticed with the NOS mid domes I put in my Q speakers and others seems the mids open up more. The coating on the mid tinsels get hard and they may be why. I'm no expert but I hear a difference.

Did you change out the mid domes Ken? Hear a difference? curious....

I sold a boat load of those mid-domes to AKers but never got any comments or feedback whether they made a differenc etc.
John M

 

[Ken Boyd]

Hey John, I started working on my QLS-1's doing a recap, cleaning the pots, and yes I replaced all the old mid domes with the new ones you sold me. But I have yet to finish the recap so the system is still down. I am going to do just one at first to see how much a difference it makes. I have the crossovers all out sitting here on my bench with the pots all opened up. That went on hold for a bit as I pulled out a pair of my QLS-2's and noticed that two of the EMIT's were not working so just the other night I pulled them all out and took them apart and reflowed the solder on the diaphrams, which took care of the problem, so now everything is working on them. I am listening to them while the big ones are down.

 

[InAp]

Funny, When I had both the 2's and qls I found the 2's more dominating, even when both were bi-amped.

 

[tubed]

I sold a boat load of those mid-domes to AKers but never got any comments or feedback whether they made a differenc etc.
John M

I also wonder, if those QLS-1 owners burned the "five dice holes" into the domes of their new mids, ala Infinity.

FWIW, I don't think
the rigid tinsel wires of the older mids would affect performance unless broken

 

[Ken Boyd]

I also wonder, if those QLS-1 owners burned the "five dice holes" into the domes of their new mids, ala Infinity.

FWIW, I don't think
the rigid tinsel wires of the older mids would affect performance unless broken

I can't say that I tried that.

 

[tubed]

I can't say that I tried that.

I imagine Infinity had a valid reason for the five dice holes unless it was an insider joke
As to your question to the more demonstrative, for a lack of a better word, relative forwardness of the Q2's mid/high section, it could be an illusion:scratch2:.
I find the Q2 very well balanced. Ditto the QLS-1.

On a side note I've been listening to a pair of recently acquired set of extremely "Holy Grail" speakers and clearly the Q's have a permanent place at my place

 

[Ken Boyd]

I imagine Infinity had a valid reason for the five dice holes unless it was an insider joke
As to your question to the more demonstrative, for a lack of a better word, relative forwardness of the Q2's mid/high section, it could be an illusion:scratch2:.
I find the Q2 very well balanced. Ditto the QLS-1.

On a side note I've been listening to a pair of recently acquired set of extremely "Holy Grail" speakers and clearly the Q's have a permanent place at my place

I have no problem with the QLS-2's as both pairs I have sound great, the mids and hi's are wonderful and balanced to the Watkins, its the QLS-1's that I feel the mids and hi's mainly the hi's to be slightly veiled. But as Micheal stated, in all fairness I need to give them an assesment after a recap.

 

[tomlinmgt]

On a side note I've been listening to a pair of recently acquired set of extremely "Holy Grail" speakers and clearly the Q's have a permanent place at my place

Sorry Ken, gotta sidetrack your thread here a little bit. Tubed is hangin' the bait out in front of us and I'm gonna take it.

Well good Lord, tubed....you just gonna keep teasin' us? :nono:

What the hell are they?

 

[Ken Boyd]

I thought everyone here knew Tubes latest great find, but is refreshing to hear that they didn't make the Infinity's sound so pathatic that he was willing to write them off. I am pretty sure I know his find, but I will let him give everyone the expose of them, but they sure looked impressive, and although he still likes his QLS-2's I would think that they are a bit better overall.

As far as the Infinity QLS-2's I have always thought of them as a wonderful pair of speakers, and to be honest, I would be just fine without their big brother as overall the QLS-2's are not that far off from the TOTL in overall sound and are much easier to deal with considering their size.

 

[tubed]

[/B]

Sorry Ken, gotta sidetrack your thread here a little bit. Tubed is hangin' the bait out in front of us and I'm gonna take it.

Well good Lord, tubed....you just gonna keep teasin' us? :nono:

What the hell are they?

Last as posted in "Dollars and Sense", quite an adventure and still is:yes:

http://www.audiokarma.org/forums/showthread.php?t=479034

I still wish someone could biamp their QLS-1 the way I described.
Something very good occurred in this configuration:scratch2:

 

[tomlinmgt]

Well that one totally got past me. Very nice, tubed!

And like Ken said, great to hear the vintage Infinities aren't so easily displaced!

Alright, back to the regularly scheduled program. Let's play with this concept. I have the Aragon 8008ST which is dual mono, almost class A with a massive dual wound toroidal transformer making 400wpc @ 4 ohms from 5hz-20Khz. I have the Souncraftsmen MA5002 making 385wpc at 4 ohms and it has L and R gain control. I also have the modified Hafler 500 making about the same amount of grunt as the SC but with MOSFETs. Tell me what combo you'd like me to try out first.

 

[tubed]

Well that one totally got past me. Very nice, tubed!

And like Ken said, great to hear the vintage Infinities aren't so easily displaced!

Alright, back to the regularly scheduled program. Let's play with this concept. I have the Aragon 8008ST which is dual mono, almost class A with a massive dual wound toroidal transformer making 400wpc @ 4 ohms from 5hz-20Khz. I have the Souncraftsmen MA5002 making 385wpc at 4 ohms and it has L and R gain control. I also have the modified Hafler 500 making about the same amount of grunt as the SC but with MOSFETs. Tell me what combo you'd like me to try out first.

Cool.
You won't be vertically biamping like me and maybe you've already done this . One mono amp each for left and right speakers lows.( EDIT: in the case of your Aragon left channel for left speaker lows and right channel for right speakers lows)
The Soundcraftsman on the left and right mid/highs channels of both speakers.
Play a tune at some realistic listening volume of your choice, then simply back off on the SC l/r gains until the (un)balance between lows and highs becomes noticeable. At that point stop then bring the gains back up until you feel there is a balance you like.
I'm comfortable with the gains governing the mids/high set about 1 o'clock on my Yamahas.
You may find you need full gains, who knows

 

[tomlinmgt]

Cool.
You won't be vertically biamping like me

That's what you wanted to try, though....right? Horizontal biamping with different amps? I'm curious to to hear the difference between the SC and the MOSFET Hafler on the top.

 

[Ken Boyd]

I don't think he particularly wanted to not vertically bi-amp them but since you don't have identical amps you have no choice.