What amp drives your Infinities?

Not sure who you are asking. The QLS1's have 2 pair of binding posts that have a jumper between. You can pull the jumper which separates the Watkins from the others. Then you can split the signal from the preamp however you like. Active crossover or just y cord. Then just feed 1 amp to watkins, other amp to mids and highs. Just use the internal crossover in the speaker. I have an active so I will give it a try both ways.

hahahaha, i know that man.....

so you are using a splitter after your preamp...(this was the part i was asking about)
my point was you are sending the whole signal from each amp without the active crossover...(highs, mids, lows) to the watkins, then same thing to the upper part of the speaker...
 
hahahaha, i know that man.....

so you are using a splitter after your preamp...(this was the part i was asking about)
my point was you are sending the whole signal from each amp without the active crossover...(highs, mids, lows) to the watkins, then same thing to the upper part of the speaker...

I guess you are asking me. Haha. As explained in post 371, mine are not yet operational. But I have accumulated enough amps to quad amp via an ACTIVE CROSSOVER and bypassing all of the passive components except for the Watkins, BUT INITIALLY will just biamp with 2 matching stereo amps. Using preamp outputs (I have 2 pair) feeding the two amps and letting the passive crossovers do their thing. Will go the ACTIVE route and bypass the passive crossovers LATER.

So highs mids and lows are never sent to the watkins. Either the signal is sent through the passive crossover (original crossover) or through the active crossover. Same goes for mids and highs.

Sounds like Zarathustra is using a y cord or something similar.

Hope that is clearer.:)
 
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Maybe this is better way to explain a couple ways I will be trying.

Scenario 1
Preamp --- Single Crown K2 500wpc --- biamp jacks bridged ---onboard passive crossovers
Scenario 2
Preamp---TwoCrown K2's --- biamp jumper removed, vertical biamp with onboard crossovers
Scenario 3. Passive bypassed except on watkins.
Preamp---Crown K2--- To watkins passive crossover
" ---Active 3 way crossover- k2 for mid woof, bogen 100wpc mids, dynaco 50wpc tweets
 
Avel Lindberg toroid ringing when on Watkins

Yesterday I installed a Kemp Elektroniks | POWER DC X-TERMINATOR (removes DC components on the AC line) and with the current setup the humming of the Avel Lindberg toroids in my Levinson ML-2's went away but the toroid in the Crown K2 which is connected to the Watkins stayed.
Then I tried to connect my Levinsons full range and one channel started to hum severly with or without the Kemp DC blocking device.
When I disconnect the amps or connect them to the mid/high section only they're silent again.
So something is wrong with the low Watkins section of my QLS's.
Any possible suspects?
I thought the 1,400 and 1,100 uF electrolytics are leaking severly or almost short?
Or something else.
I'll try the remove the woofer tonight to check the components and wiring inside the cabinet.
 

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i've personally never known a hum to come from the speakers themselves...usually the hum comes from one of the components...

do you have another set of speakers to test...?
 
i've personally never known a hum to come from the speakers themselves...usually the hum comes from one of the components...

do you have another set of speakers to test...?

The hum comes from the toroid in the ML-2 amp but only when connect to one of the lowfreq terminals (Watkins woofer) of my QLS-1.
When I connect another amp to these terminals. my Crown K2) it hums also severly.
 
Is it acting the same on both speakers? The hum is only from the transformers in the amps not the speakers, correct? Are the woofers AND the other drivers sounding normal? Possibly reduced or increased output on any drivers?
 
Yes I do dial down the output of the K2 but not a whole lot.
You gonna use the K2's in bridged mode on the Watkins?
Bridging means more power (Voltage doubling) but the same current so maybe not a favorable solution with tougher loads... Maybe a moot point with the K2's though :D

But how about Conrad Johnson Premier Five on the mid/bass section of the QLS?
I know Nudell always favored tubes on his big speakers. The RS-1 sounded the best with the CJ's on de mid/high towers according to the reviewers.
Only thing I'm worried about is the running these CJ's and buying a new set of 22 tubes every two or three years.
Use VTLs. Only 16 tubes every two or three years.:D
 
Is it acting the same on both speakers? The hum is only from the transformers in the amps not the speakers, correct? Are the woofers AND the other drivers sounding normal? Possibly reduced or increased output on any drivers?

The hum is only from the Levinson ML-2 mono-amplifier that's connected to the left QLS low frequency section or when the Crown K2 is connected it hums also from the amp but somewhat less.
 
I'm far from an expert, but sounds like (no pun intended) an issue with the low frequency portion of xover or the Watkins. If you switch woofers and it moves with woofer, then it's the watkins. If it stays, then probably the crossover. Might want to check the dcr on the low frequency biamp jacks and compare to other cab. Maybe it's putting an unusually heavy load on the amp? Are the transformers hotter than normal?
 
I'm far from an expert, but sounds like (no pun intended) an issue with the low frequency portion of xover or the Watkins. If you switch woofers and it moves with woofer, then it's the watkins. If it stays, then probably the crossover. Might want to check the dcr on the low frequency biamp jacks and compare to other cab. Maybe it's putting an unusually heavy load on the amp? Are the transformers hotter than normal?
Thanks, I will try that of course but somehow the wrench I used on the screws around the Watkins of my Q2 does not fit on my QLS's.
I reckoned it's the low frequency portion that causes the problem, but I could not come up with a possible cause. I have to investigate further though there your right. I will keep you posted.
 
Thanks, I will try that of course but somehow the wrench I used on the screws around the Watkins of my Q2 does not fit on my QLS's.
I reckoned it's the low frequency portion that causes the problem, but I could not come up with a possible cause. I have to investigate further though there your right. I will keep you posted.

I would test resistance on low freq jacks before pulling woofs. Might tell you something b4 digging in too deep. Goodluck.
 
I would test resistance on low freq jacks before pulling woofs. Might tell you something b4 digging in too deep. Goodluck.
Resistance: MM says at both terminals of both speakers 'OL' Open Loop...

Got out the Watkins and the Xover is completely overhauled as it seems.
The Callins 1,400 and 1,100 uF are gone and substituted by three and twe 470 uF axials. Pots are brand new and shining. Saw some 'Audyn' caps.
Coils measured:
VC1: 5.0 Ohms
VC2: 2.1 Ohms
Not sure about which coil had the lower reading but these values I remember correct.

To come back to one of my first questions:
Does anybody has any experience with the Conrad Johnson Premier Five on the mid/high section of the QLS or maybe a Audio Research M300 or D250?
I know that Nudell liked it that way.
 

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holy shinny pots...

when you swapped speaker leeds left to right the hum stayed at the speaker in question...?
 
Resistance: MM says at both terminals of both speakers 'OL' Open Loop...

Got out the Watkins and the Xover is completely overhauled as it seems.
The Callins 1,400 and 1,100 uF are gone and substituted by three and twe 470 uF axials. Pots are brand new and shining. Saw some 'Audyn' caps.
Coils measured:
VC1: 5.0 Ohms
VC2: 2.1 Ohms
Not sure about which coil had the lower reading but these values I remember correct.

To come back to one of my first questions:
Does anybody has any experience with the Conrad Johnson Premier Five on the mid/high section of the QLS or maybe a Audio Research M300 or D250?
I know that Nudell liked it that way.

Funny how we tend to ignore the original question sometimes. :) With the QLS1 being somewhat rare, it may be difficult to find someone who used that specific combo. But not impossible.:)
 
Funny how we tend to ignore the original question sometimes. :) With the QLS1 being somewhat rare, it may be difficult to find someone who used that specific combo. But not impossible.:)
Still have the QLS's but now connected to a Conrad Johnson EVO2000 hybrid amp (four 5751's pre-driverstage and MOSFet drivers and Powertransitors)
Have a Krell KSA-100 mk2 for the Watkins but the EVO2000 seems to manage the QLS perfectly by its own.
For comparison I bought a Perreaux PMF3150 MOSFet amp and I'm curious how this one performs.
Infinity is a keeper I'm so very pleased with it!
 
Twin MC 2200, fresh from Terry, strapped for 400 watts mono.
View attachment 1384420

Barely enough for the QLS-1!
View attachment 1384419
I want to hear a pair, properly amplified, in a proper room. as much of a fan as I am of my RS 2b,(and I prefer them over any of the Kappa series I've owned) I'd like to hear the QLS.

Ah, well.

Some day, maybe.

BTW, nice collage of the American flag, Canadian flag, and the all important freak flag! (Tie Dye)
 
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