Jump to content
The Classic Speaker Pages Discussion Forums
lollo85

Allison One woofer replacement

Recommended Posts

Good quality drivers but you should follow Pete's recommendations of adding inductors and additional mass. Hope you are successful resurrecting those great speakers. Please report back on your progress. And we (I) love photos :rolleyes:

I'll be interested to see what, if any, cabinet mods are needed for the new woofers.

Kent

Share this post


Link to post
Share on other sites

Thanks Jkent, today I brought the speakers to the carpenter to change the hole, and restore the wood, soon I will insert the pictures.

Meanwhile,I thank you and Pete for important informations and support

Share this post


Link to post
Share on other sites

Both are correct. You don't need to use a heavy gauge inductor the single 1 mH is good and 18 ga is fine.

Share this post


Link to post
Share on other sites

Nice work! How do they sound?

Share this post


Link to post
Share on other sites

Thanks for reply Pete. My budget is around $ 450, but i prefer to find something from the catalog, are not very experienced in making these experiments.

Searching the internet, I found 2 interesting woofer, what do you think?

I enclose the translation of the original specifications of the woofer allison.

Sensitivity (dB-SPL)2.83volts@1meter 87+

Nominal Loudspeaker Imp. (Ohms) 4

Voice Coil DC Resistance (Ohms) 3,1

Magnetic Gap Flux Density (Gauss) 8.000

Magnet Weight (Oz.) 19

Magnet/Assembly Weight (Oz.) 53

Magnetic Gap Height (Inches) 0,37

Voice Coil Winding Total Length (Inches) 0,87

Total Voice Coil Overhang (inches) 0,5

Voice Coil Linear Excursion Xmax (+/- inches) 0,25

Nominal Voice Coil Diameter (Inches) 1,5

Effective Diaphragm Piston Diameter (Inches) 8,4

Diaphragm Weight (Grams) 54

Fs - (Hz) - Free Air Resonance of Driver 22

Voice Coil Damping/Cooling Material None

Qms - Q at Fs, Mechanical Resistance Only 2,74

Qes - Q at Fs, Electrical Resistance Only 0,59

Vas(cubic inches) - Volume of Air with Same Compliance as the Driver Suspension 9.281

Continuous or Avg. Power Handling at Any Frequency (Watts) 250

check out this woofer, and tell me what do you think:

http://www.scan-spea...26w-4534g00.pdf

also this:

http://www.ciare.com...logo/CW256Z.pdf

So are these the scanspeak woofers you used, the 26W/4534G00? Looks awesome. So, let us know how your testing results come out.

Share this post


Link to post
Share on other sites

the sound is great, the bass is not exaggerated, I like it so much; but my nad 3240pe (40w +40 w) is a little effort. I should find a more powerful amplifier.

The speakers are Scanspeak 26W/4534G00 4 Ohm

26W-8534G00.jpg

Thanks Pete for the support

Share this post


Link to post
Share on other sites

I use an SAE 2401 (250 watt/ch) with my Allison One's. Gives them the "grunt" they need.

Share this post


Link to post
Share on other sites

the sound is great, the bass is not exaggerated, I like it so much; but my nad 3240pe (40w +40 w) is a little effort. I should find a more powerful amplifier.

The speakers Thanks Pete for the support

You're welcome, nice to see them working again!

Please let us know how they work out with more power if you do get another amp, or any futher comments you might have.

Share this post


Link to post
Share on other sites

Okay gentlemen. First, let me say that you have totally left me in the dust with all of this techno-talk. However, I recently had a rubber preservative product from a very well respected company cause the rubber surrounds on the woofers of my primary speakers to crinkle up like the Wicked Witch of the West. Tim Stinson of Luminous Audio Technology and Albert Von Schweikert collaborated on the speaker design. The speakers are prototypes that originally came with Peerless 831759 woofers, but those drivers are NLA. Albert Von Schweikert suggested the Scan Speak 26W/4534G woofers as the closest replacement available for the ruined Peerless drivers. I ordered a pair of the Scan Speak drivers. Getting them to fit was a real bear, because it is hard to cut through inch-thick MDF with a cheap jig saw. However, the deed was done, and the woofers sound quite nice, especially after the surrounds had some time to loosen up. I would say that to my very untrained eye, the Scan Speak drivers looked reasonably well-made. I am no expert on this topic, but the Scan Speaks got my main speakers going again and the bass sounds quite nice. I cannot say that the drivers are perfect for your application, but I would not hesitate to use the Scan Speaks, IF they are close to what you need, specification-wise.

I am lucky that I had my Dyna A-50's to fall back on while the melodrama of the ruined woofer surrounds played out.

Randy

Share this post


Link to post
Share on other sites

I have apparently done what I do best...confuse myself. I thought I was at the end of the thread when I posted the above comments.

I am glad the drivers worked out for you. It was not a bad idea to have a carpenter do the woodworking part of the job on a pair of classic speakers like those. They look really nice, and I bet they sound nice too. The Scan Speak woofers have a very nice, controlled sound.

I agree that you might be able to use more power. Keep us informed.

Randy

Share this post


Link to post
Share on other sites

I recently had a rubber preservative product from a very well respected company cause the rubber surrounds on the woofers of my primary speakers to crinkle up like the Wicked Witch of the West.

Bummer. But if that's all that's wrong I hope you did not chuck them. Surrounds are easily and cheaply replaced. Either buy a kit from MSound or ship them out to Millersound to have it done professionally.

So do you still have the Witches?

Kent

Share this post


Link to post
Share on other sites

Yes, I do. They are sitting on the floor behind me as I write this. The folks I contacted all wanted to put foam surrounds on the Peerless drivers, which would alter their characteristics to an unacceptable degree. The original surrounds are Butyl rubber.

The product I used is called "CaiKleen RBR," which is marketed by Caig. The product worked great on everything from RTR tape rollers to automotive wiper blades. It didn't damage the Focal Kevlar upper-bass/midrange drivers in my main speakers, the woofers in my A-50's, or the Scan Speak drivers I bought to replace the Peerless units. However, the surrounds on the Peerless drivers shriveled up before my eyes, one more than the other.

My speakers do not use grilles of any kind, which means the drivers have been exposed to a fair amount of sunlight over the years. The Focal drivers were replaced some years ago, but the Peerless drivers were the original ones. I don't know if exposure to UV light had anything to do with the surrounds' demise or not. I just know that I was bummed when it happened!

Randy

Share this post


Link to post
Share on other sites

If anyone on the planet can repair the woofers properly it's Bill LeGall of Millersound. Try emailing him and tell him your problem: Millerspkr@aol.com

Share this post


Link to post
Share on other sites

Hello Kent--

I may do so, but I expect the Scan Speak woofers/subwoofers, (below 100 hz. in this design,) will probably last me until I am deaf, dead, or both. I would like to have the Peerless drivers fixed, but...then, I would have to find something to do with them. I am not sure that they would still fit into the openings in my subwoofer cabinets. I had to enlarge the openings a surprising amount to get the Scan Speak baskets to fit in the holes that were orginially cut, much more nicely, for the Peerless drivers.

I wish I had stumbled onto this forum sooner. I have cut and pasted your last post with the gentleman's email address. Thank you very much.

Randy

Share this post


Link to post
Share on other sites

If anyone on the planet can repair the woofers properly it's Bill LeGall of Millersound. Try emailing him and tell him your problem: Millerspkr@aol.com

He will be rehabbing the last 2 of my mids later this year. I also am doubly blessed as door-to-door for me is a 40 minute drive to hand deliver to Bill.

Share this post


Link to post
Share on other sites

The Eclipse W1038R is back in stock at Madisound. I have a feeling that they have hundreds of them:

http://www.madisoundspeakerstore.com/eclipse/

This is an 8 ohm driver and we needed 4 ohm to put them in series.

I came up with a solution that looked excellent where I put them in parallel for 4 ohms,

then added significant series resistance to bring them back up to about 6 or 7 ohms

which was required anyway because the motor is too strong. It was looking good

in simulation but I didn't finish the work. If anyone wants to try this let me know and I'll

see what I can come up with. These are excellent drivers.

Share this post


Link to post
Share on other sites

Speaking of Allison One woofers, does anyone know what kind of dope was originally used on the cones & surrounds? The cones look new and are still nice & tacky, but the foam surrounds are starting to deteriorate. I am going to replace the foam surrounds and would like to use the same kind of sticky, black dope that was originally used. I suspect that most today's common dope products would melt a foam surround.

Share this post


Link to post
Share on other sites

Speaking of Allison One woofers, does anyone know what kind of dope was originally used on the cones & surrounds? The cones look new and are still nice & tacky, but the foam surrounds are starting to deteriorate. I am going to replace the foam surrounds and would like to use the same kind of sticky, black dope that was originally used. I suspect that most today's common dope products would melt a foam surround.

The material was a butyl/latex compound similar to the treatment on very early AR foam surround woofers. There is nothing available today which will not compromise the compliance of foam. You are better off not applying anything at all.

Roy

Share this post


Link to post
Share on other sites

Thanks, Roy. I'll keep them uncoated and will report back when I'm finished.

Share this post


Link to post
Share on other sites

Speaking of Allison One woofers, does anyone know what kind of dope was originally used on the cones & surrounds? The cones look new and are still nice & tacky, but the foam surrounds are starting to deteriorate. I am going to replace the foam surrounds and would like to use the same kind of sticky, black dope that was originally used. I suspect that most today's common dope products would melt a foam surround.

I sound like a broken record in this thread. Bill LeGall just fixed the one woofer I have that I wrote about had the buzzing noise when certain soundtracks were played. He has come up with a replacement formula for the coating and used in on my woofer and it looks awesome! I can post a pic of it is anyone wants to see it. Oh and the buzzing noise is long gone!

Share this post


Link to post
Share on other sites

I sound like a broken record in this thread. Bill LeGall just fixed the one woofer I have that I wrote about had the buzzing noise when certain soundtracks were played. He has come up with a replacement formula for the coating and used in on my woofer and it looks awesome! I can post a pic of it is anyone wants to see it. Oh and the buzzing noise is long gone!

Yes, I would like to see it. Thanks.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...