Infinity Quantum 4 Questions

[Yamahalic]

I just inherited a pair of these (actually, raised my hand when the family said is there anyone who wants them). My father-in-law had some good taste in the old days as he had these and a pair of AR-4x speakers (I got those too).

I am a BIG fan of Infinity, and paired with my Yamaha electronics has really worked well for me of the past many years. I refoamed my SM-122s a while back because I could not find any towers that sounded better, but these Quantum 4 speakers are something special.

Anyway, I wanted to ask Quantum owners, and/or those in the know as to what I should look for as I bring these back to life. The woofers need a refoam, so I am thinking about the Watkins service.

One grille frame is separating from the grille body, any suggestions on a proper adhesive to use?

The cabs seem like solid wood, is this the case?

Should I look for anything else while I am in there? I was probably going to leave the other drivers alone and try them out after the woofers come back, that is unless there is something I should do to them in the meanwhile.

 

[goat67]

I just inherited a pair of these (actually, raised my hand when the family said is there anyone who wants them). My father-in-law had some good taste in the old days as he had these and a pair of AR-4x speakers (I got those too).

I am a BIG fan of Infinity, and paired with my Yamaha electronics has really worked well for me of the past many years. I refoamed my SM-122s a while back because I could not find any towers that sounded better, but these Quantum 4 speakers are something special.

Anyway, I wanted to ask Quantum owners, and/or those in the know as to what I should look for as I bring these back to life. The woofers need a refoam, so I am thinking about the Watkins service.

One grille frame is separating from the grille body, any suggestions on a proper adhesive to use?

The cabs seem like solid wood, is this the case?

Should I look for anything else while I am in there? I was probably going to leave the other drivers alone and try them out after the woofers come back, that is unless there is something I should do to them in the meanwhile.

I used the Watkins service for my Q5s fast and done right.

For the frame I used regular old Elmers glue IIRC. Just spread some on thinly and put something heavy on it to let it set.

Nope Cabinets are Walnut veneer (sp?) over MDF use some Howards Wax and Feed to make them beautiful.

While you have the Woofers out get inside and remove the mid and treble pots,
they need to be taken apart and cleaned they will be full of corrosion..

Also check to see if the back panel where the controls are mounted is sealed real good.

I used some caulk or silicon and sealed mine up. I think this was my first post
here at AK asking why I heard huffing from the speaker.

I think you will like these speakers if you have an AMP that can drive them.

They will laugh at 250W and they will cry if they have less than 100W

 

[jt45]

Congrats on your quantums, nice speakers. If you decide to refoam them yourself, there's plenty of Infinity owners here to help you out, as they did me. Good luck getting those shined up and singing again !

 

[elnaldo]

Congratulations !!!!!

Do you have this tech sheet?
Quantum_4_technical_sheet.pdf

What about a recap? I don't know what kind of caps are inside those Quantum 4....

 

[avguytx]

I see that those Watkins woofers have the same big a$$ capacitors in the circuit like my Quantum 3's have, too. I replaced those big cans with Bennic electrolytic caps from Madisound because they were WAY out of spec....unless that's how they were intended. lol. Just verify that those caps are in your actual speakers and not rely solely on the data sheet because sometimes there were running changes. It all depended on what was in the parts bins on any given day it seems like....that and what suppliers they were working with.

 

[tubed]

The Quantum 4 is my first audiophile(excuse the expression) speaker I purchased in 1977.
My ex girlfriends' brother worked at Infinity and recommend these which were "seconds" and cost me $100 apiece new.
I listened to them for 20-something years on my first real Yamaha CA-1000 integrated amplifier.
I still have them but are out of the line up for now....the Watkins in a smaller cabinet doesnt go as low as applied in larger volumes however the bass response is very fast and 2 ohm musical moments are quite distinct and visceral....hard to find a better 12" 3-way IMHO

 

[Yamahalic]

...I listened to them for 20-something years on my first real Yamaha CA-1000 integrated amplifier.

Ah, another successful Yamaha/Infinity pairing. Many others have discovered our little not-so-well-kept secret. Your photo looks like a screen over the front, did the screen come with yours, and/or was it an option from Infinity, or ?

Another question...Your Q4s and some others I have seen have a black surface finish on the EMITs, versus mine are silver. Anyone have an idea as to why that might be, perhaps an indication of the build year? :scratch2:

 

[tubed]

Ah, another successful Yamaha/Infinity pairing. Many others have discovered our little not-so-well-kept secret. Your photo looks like a screen over the front, did the screen come with yours, and/or was it an option from Infinity, or ?

Another question...Your Q4s and some others I have seen have a black surface finish on the EMITs, versus mine are silver. Anyone have an idea as to why that might be, perhaps an indication of the build year? :scratch2:

Yes, the CA-1000 is a very special thing.
I believe the "black" EMITs were featured on the Q4s only.
After years of abuse(parties, painting the living room, kitty cats etc) the original grills didnt survive...so I used heavy duty black diamond lathe that suited me just fine. Enjoy!

 

[Yamahalic]

Midrange Drivers

Another question, I was looking at the midranges, and they seem to have a wire that goes into the dust cap on each driver from the top and bottom. In my case, some are severed, bit I cannot see a wire in the broken sections which I find odd. So, maybe a very small wire was in there? Does not seem like it will be easy to fix at this point, any suggestions?

 

[tubed]

Another question, I was looking at the midranges, and they seem to have a wire that goes into the dust cap on each driver from the top and bottom. In my case, some are severed, bit I cannot see a wire in the broken sections which I find odd. So, maybe a very small wire was in there? Does not seem like it will be easy to fix at this point, any suggestions?

If enough wire is showing it's fixable.
Obtain a small artists brush, a small can of Stryp-eze paint remover and a small pair of jewelers pliers.
Soften the resin surrounding the tinsel wire by applying successive coats of Stryp-eze and after softened, crush the coat(rather than pulling) with the flat nosed pliers. Clean off tinsel....solder a new lead and viola!. A working mid

 

[Yamahalic]

12" Infinity-Watkins Woofer Versions

O-k, I removed my woofers to take a look at them. My woofers look like a paper design versus the poly ones (I presumed them to be an older design). But, when I removed them, I was still hoping to see a traditional 902-1180 design such as is found with the poly cone designs I have seen. But, my woofers have a smaller magnet structure, and they are lighter in weight than I expected. I found on them odd serial numbers: 4 514 32?? (can't make out the last 2 digits).

So, I am guessing Infinity went "cheap" (o-k, maybe "more budget minded) towards the end of the model(s) run, and down spec'd soem QLS models to lower the price, perhaps to move them out to make way for newer models in the pipeline.

I contacted Mr. Watkins for comment, and he said that Infinity changed to a cheaper woofer in later models, and that my woofers are of the later/cheaper design. That said, I must decide the relative value of these newer/cheaper woofers for my decision to repair or replace.

So, can any of you out there, that have any of the QLS models with the paper cone type newer driver, please comment on your thoughts on these? Mr. Watkins says the older design has less distortion, deeper bass, and higher power handling, and that his company only makes the 902-1180 design.

Based on photos, I believe that 902-1180 to be a superior design, but how much is the key point here. If the 4-514 versions were say 80% as good as the 902s, then I might choose to repair them (at least for now). I know this is subjective, but I still would like to hear from AKers that might want to chime in on this subject.

 

[tubed]

Wierd.
I have a direct from the factory pair(literally) of Q4's manufactured in 1977 with the early model paper cone without any "number" indicated. They have a smaller magnet than that of the polycones on the QLS-1 and the paper coned Q2.... they are original and maybe the magnet is smaller made with a more powerful magnet alloy?
Are you positive you have Watkins or a replacement dual voice coil woofer of some other maker?
Pics are in order

 

[SicMan]

JUST A Note:
The Watkins dual drive woofers have 2 sets of terminals on them, and are usually labeled 2 ohms and 4 ohms.

 

[Yamahalic]

Wierd.
I have a direct from the factory pair(literally) of Q4's manufactured in 1977 with the early model paper cone without any "number" indicated. They have a smaller magnet than that of the polycones on the QLS-1 and the paper coned Q2.... they are original and maybe the magnet is smaller made with a more powerful magnet alloy?
Are you positive you have Watkins or a replacement dual voice coil woofer of some other maker?
Pics are in order

Well, it was Bill Watkins himself that told me after seeing my driver, "...you have the cheaper woofer as used in the later production units." Sadly, the better 902-1180 driver was listed as the woofer on the QLS-4 tech sheet I found, but apparently, Infinity must have decided to downspec the QLS-4 (maybe others), perhaps it was a sales issue. Bill Watkins adds about the 902 driver, "...It was retained in the QLS, Quantum 2 and 3, where the speaker price could afford it's usage."

So, my driver is most likely a unit installed by Infinity later in the production of the line. Not sure how it might compare to your paper driver (do you have photos?). Bill seems to indicate the "902" driver with the larger magnet was originally used. I can say that my "514" driver feels really cheap to me (light in weight, unimpressive stamped metal cage, no branding of any kind). You can clearly see that it is a dual voice coil in my attached photo (note opposing leads on each side of the driver).

So, my dilemma is to fix these older/cheaper drivers, or perhaps pay $474/pair from Watkins Engineering to buy new poly cone 902 drivers (ouch). I am inclined to refoam these old drivers, but I wasn hoping to get some input on them first.

 

[tubed]

I've got the same driver in my Q4s.
Also it looks exactly like the same build as the Watkins woofer from my Quantum 2, except the Q2 driver does have a larger magnet and larger voice coil....
That said I believe the Q4 woofers were manufactured and supplied by Watkins and were appropriate for the Q4 and much smaller Q5.

 

[jt45]

O-k, I removed my woofers to take a look at them. My woofers look like a paper design versus the poly ones (I presumed them to be an older design). But, when I removed them, I was still hoping to see a traditional 902-1180 design such as is found with the poly cone designs I have seen. But, my woofers have a smaller magnet structure, and they are lighter in weight than I expected. I found on them odd serial numbers: 4 514 32?? (can't make out the last 2 digits).

So, I am guessing Infinity went "cheap" (o-k, maybe "more budget minded) towards the end of the model(s) run, and down spec'd soem QLS models to lower the price, perhaps to move them out to make way for newer models in the pipeline.

I contacted Mr. Watkins for comment, and he said that Infinity changed to a cheaper woofer in later models, and that my woofers are of the later/cheaper design. That said, I must decide the relative value of these newer/cheaper woofers for my decision to repair or replace.

So, can any of you out there, that have any of the QLS models with the paper cone type newer driver, please comment on your thoughts on these? Mr. Watkins says the older design has less distortion, deeper bass, and higher power handling, and that his company only makes the 902-1180 design.

Based on photos, I believe that 902-1180 to be a superior design, but how much is the key point here. If the 4-514 versions were say 80% as good as the 902s, then I might choose to repair them (at least for now). I know this is subjective, but I still would like to hear from AKers that might want to chime in on this subject.

I have some QLS1s with Original woofers and they are paper coned, it seems they switched these as well as some other things in the Quantum line.
Good luck with repairing the tinsel wire on your midrange they are PITA to fix, but it can be done http://www.audiokarma.org/forums/showthread.php?t=322722&highlight=Middome+repair
Here is a pic of my QLS1s with paper cone woofers.That I refoamed with help here in the infinity forum.

 

[Yamahalic]

I have some QLS1s with Original woofers and they are paper coned, it seems they switched these as well as some other things in the Quantum line.
Good luck with repairing the tinsel wire on your midrange they are PITA to fix, but it can be done http://www.audiokarma.org/forums/showthread.php?t=322722&highlight=Middome+repair
Here is a pic of my QLS1s with paper cone woofers.That I refoamed with help here in the infinity forum.

Sadly, I guess my woofer is of a cheaper design, which seems more apparent in the magnet and cage structures. The paper cone seems fine to me, so I may go ahead and refoam.

Thanks for the tips, but I am wondering about your photo...those look like poly woofers in the image, did you change your cones from the paper type? If yes, did you notice a difference?

 

[tubed]

Sorry you feel slighted with the "small" magnet Watkins woofer:tears:.
However once you are successful at repairing the midrange, you might what to consider dropping in a pair of these for that feeling of substantial fulfillment:yes::

 

[jt45]

Sadly, I guess my woofer is of a cheaper design, which seems more apparent in the magnet and cage structures. The paper cone seems fine to me, so I may go ahead and refoam.

Thanks for the tips, but I am wondering about your photo...those look like poly woofers in the image, did you change your cones from the paper type? If yes, did you notice a difference?

No they are the original woofers, I refoamed them is all and plan to re-capp them at some point. Ive seen paper cones on both the earlier and later versions and more poly cones on the later versions, I think you will be happy with those they are capable of putting out very good bass down to 18hz I think. If you havent already done so you can get more info Here.

Also here is a link to a thread I started that contains info for refoaming those as well as links to other DYI projects from members here that helped me http://www.audiokarma.org/forums/showthread.php?t=317580

 

[Ken Boyd]

The paper cones with the smaller mags are the orginal WDVC drivers. The newer drivers are the poly ones. I have three sets QLS 2's, all having the paper cones and smaller mags and they produce very low tight bass. My QLS-1's have the poly cones, but some versions have the paper cones. I also have a pair of the QLS-5s and they have a poly cones. All of the larger QLS models use EMIT's with black surfaces and the smaller versions like the 5's and QA's use a silver EMIT. As far as those mids, I have repairs quite a few of them and I always pulled the diaphram out and replaced the tinsel wires from the terminal to the back side of the cone and that is where I made my solder connections. Where the wire comes off the voice coil you have to clean the brown insolation off and then tin it and use new winding wire and poke it out to the front side and after digging out the old wire from the channel you run the new wire down the channel and solder it to the terminal. I used an adhesive and glued the solder joint to the back of the dome like it orginally was and then on the front side I use some black dope in a can and coated the tinsel wire from where it pokes threw and all the way down the channel. It is a very time consuming job I and recommend useing one of those jewelers lite mag lights on an arm. A few of the many that I repaired I was unsuccessful as getting a good clean surface free of that brown glue is very hard to do as the residue prohibits you from always getting a good solder joint.

As far as the bass drivers your not going to get 18hz out of your model because of what was already posted, your smaller cabs! But if they were mine I would just refoam the drivers you have as long as the voice coils don't have any rub and I think you would have a nice pair of speakers, that you will probably be happy with.