Brought home a pair of QLS 1's today.

rpampt

Analogeous Vinylitis
Well it looks like I determined what my next project is. :) Cabs good, majority of drivers working. Controls need some work. Even with a few mids not working, I can hear the potential for some Infinity magic.
 
Congratulations! Those are some rich sounding speakers. This is going to be a satisfying project.

The controls can be easily disassembled for cleaning. ALL the electrolytics in my pair were leaking. The domes tend to fail in pairs.

They like BIG power to sound really good, internet legend has it that they have a sensitivity of 82dB!
 
Congrats on a great pair of speakers. I think you will be surprised when the project is over......... And happy. :yes:
 
Yes, I'm looking forward to restoring them. I have a 100 wpc tube amp that should be stable, even with the heavy load of the Watkins woofs, but while stable, it's probably not powerful enough to get them singing at their optimum. A couple SS amps I have can probably do OK, but still no more than 150wpc. I thought of horizontal biamping using a higher wattage pro amp on the bottom and tubes on top, but then have the imbalance of amps to deal with. So will spend some time considering my options while working my way through the restoration process. I've been in the tube amp and high efficiency speaker camp for awhile, but I couldn't pass these up.:)
 
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I thought of horizontal biamping using a higher wattage pro amp on the bottom and tubes on top, but then have the imbalance of amps to deal with.

If you have this option available I recommend you give it a try, its not that hard to play around with getting things sounding great, I have been doing so on a pair of 2.5s.
 
Sure, tubes up top, SS downstairs! An active crossover would take a lot of pressure off those amps, too. Bryson 10b has a great reputation.
 
Sure, tubes up top, SS downstairs! An active crossover would take a lot of pressure off those amps, too. Bryson 10b has a great reputation.

I guess an active crossover along with the passive crossover components may work for balancing the amps, but completely bypassing the internal crossover and using only an active? With all those drivers and additional eq controls and complicated crossover, I don't know how easy it would be to get everything dialed in. I've never used an active crossover before, but have a simple one that's never been removed from the box.

Should be a fun project to work through. A friend of mine has 2 Bryston (7 B I think) 500watt monoblocks he'd like to sell me.......But I'm cheap.
 
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Congrats on aquiring a great pair of speakers!

Mine are currently apart sitting on two work tables, waiting for things to slow down at work a bit, so I have the time to dig into them and rebuild the crossovers.
 
I guess an active crossover along with the passive crossover components may work for balancing the amps, but completely bypassing the internal crossover and using only an active? With all those drivers and additional eq controls and complicated crossover, I don't know how easy it would be to get everything dialed in. I've never used an active crossover before, but have a simple one that's never been removed from the box.

Should be a fun project to work through. A friend of mine has 2 Bryston (7 B I think) 500watt monoblocks he'd like to sell me.......But I'm cheap.

Ive wondered about bypassing the internal crossover and using an active crosover myself, hope others in the know will weigh in on this...
 
I don't think anyone's recommending bypassing the passive crossover. I certainly would not advise that. The active crossover is simply used to reduce the load on the amps by passing only low frequencies to the bass amp and mid-bass and higher frequencies to the amp running the rest of the drivers.

Congratulations on acquiring a fine set of speakers!
 
I don't think anyone's recommending bypassing the passive crossover. I certainly would not advise that. The active crossover is simply used to reduce the load on the amps by passing only low frequencies to the bass amp and mid-bass and higher frequencies to the amp running the rest of the drivers.

Congratulations on acquiring a fine set of speakers!

Yes! The idea is to feed the woofer amp ONLY the frequencies that will be allowed through the existing passive crossover in the speakers, same for the upper frequencies. That way the amp is not "working" to produce any sounds that will not be used by the speakers that it is powering. In other words, the crossover goes between the pre amp and the main amps.
 
I've found a few of the diy threads on tinsel wire repairs, but is there a go to guy on AK that does the repairs at a reasonable cost?
 
You can try *Around the sound in Seattle, WA.* They did a great job on my mids for $30 each. You have to act fast, he is retiring soon. The shop number is 206-782-7975.
 
I guess an active crossover along with the passive crossover components may work for balancing the amps, but completely bypassing the internal crossover and using only an active? With all those drivers and additional eq controls and complicated crossover, I don't know how easy it would be to get everything dialed in. I've never used an active crossover before, but have a simple one that's never been removed from the box.

Should be a fun project to work through. A friend of mine has 2 Bryston (7 B I think) 500watt monoblocks he'd like to sell me.......But I'm cheap.

Full active and bypassing all the passive crap is the ONLY way to go if you actually want to accomplish something worthwhile. The cheapo crossover in my sig would work fine (all 2nd order just like Infinity) and sounds just fine. Pro amps (fanless) on the bottom are indeed the way to go. Have fun! "Dialing in" the level match between drivers is extremely easy if you've gotten the crossover points and the slopes right. You just keep fine tuning it while listening until all recordings sound right.
 
From the Man himself. Bill Watkins directly replied to an [Infinity Classics] discussion, concerning this very subject; biamping a Watkins woofer based system. Mr. Watkins was against removing his crossover circuit, and actively biamping his woofers. Specifically; this "would do away with the benefits of the dual-drive." His comments to my answer to another Classics member:


"To Mr. Weaver and Dr. Marks:

Re your discussion on the Watkins dual-drive woofer configuration: Dr. Marks comments are in quotes:

"All speakers will / would benefit from Multi-Amplification."

Opinions vary. A well designed simple two-way system might not.

"If you wanted to do this to a Watkins woofer you would / could Bi-AMP the woofer.
Remove all it's external crossover components and use a stereo AMP one channel for each voice coil.
Set your Electronic Crossover to the resonant frequency of the 4 Ohm Voice coil section in the cabinet ( typically 30-40 Hz of so ) and drive each voice coil with a separate channel of the amplifier ( yes - Bi-AMP your Watkin's woofer )."

This would do away with the benefits of the dual-drive:
1. Limit the power intake and acoustic output in the low bass.
2. Increase the dual-drives low phase shift of almost zero to around the usual 90 degrees.
3. Revert back to the detrimental impedance increase of a factor of about four.
4. Do away with a properly implimented dual-drive's guarantee of flat response into the very low bass.
5 Increase distortion.

"So the 2 Ohm coil would operate from about 20 Hz to 40 Hz and the 4 Ohm coil would operate from about 40 Hz to 100 Hz ( I am just saying ). You treat each voice coil as if it is it's own separate speaker.
It is as simple as that."

To biamp and retain the dual-drive's advantages and it's solid clean "soul-satisfying" sound, the electronic crossover should be set to around 100 to 200 Hz.

Bill Watkins
Watkins Engineering
watkinsstereo.com"
 
You can try *Around the sound in Seattle, WA.* They did a great job on my mids for $30 each. You have to act fast, he is retiring soon. The shop number is 206-782-7975.

Thanks. I was able to make contact today, but Carcel is retiring early next week and I couldn't get them to him in time. I tried to explain them to him but he didn't recollect by my description what they were. He may have retirement on his mind. They did recommend JaMac as an alternatve, a fellow named Ron. So I spoke to him and he knew Carcel and said Carcel had worked with him for 40 years at JaMac I believe. Anyway, he was not interested in taking them on for fear of making a repair that might be short lived.

Any other ideas are appreciated.
 
How many mids are out? They can be had on Ebay but not cheaply.

Can't get into them too deeply yet. Some medical issues need to heal first before I can spend much time with them. I'm just trying to get ahead of the game.

I know at least 2 of them have broken leads. May be a couple more, but won't know until I can do some testing, clean up the switches and controls and such. I've seen them on ebay and can drop a lot of $$$ if you need many!
 
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