Pete B
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Posts posted by Pete B
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Yes they are, I'll PM you
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Bump to get this back on track, gorgeous $499 :
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Bump, price drop to $599
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Bump and price drop over
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Bump
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@claudel Any chance these are still available?
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On 2/6/2019 at 2:34 PM, JKent said:
I don't know of other woofers that would work but that's where Bill may be able to help. He's a speaker wizard. If he doesn't have a single Cizek woofer to sell you'll probably have to replace the pair. They're 4 ohm, which makes it a bit trickier. Call him (don't email). He's a very good guy and will answer your questions.
If you go back to the thread I linked above you'll see several pics of the fronts of the woofers. Below is a pic of the back, with its massive magnet. Looking at yours, the one on the left appears to have a plastic cone, so that's not original. The one on the right looks like it's paper but the dust cap is domed. All 4 of my woofers have flat dust caps. You may have to pull the woofers to check.
The cloth grilles are unlikely to have a negative effect. After all, nearly all speakers have cloth grilles.
Regarding the odd speakers, no--they did not attempt to add a mid. That's a port and it's a legitimate design but NOT anything like the original Cizeks (and AR, KLH, Advent, Boston Acoustics, etc. etc.) which were sealed acoustic suspension speakers. I'm guessing the builder of those just liked the koa wood cabinets. The front baffle does not look home-made so maybe he took an existing speaker of similar size and just transplanted everything to the Cizek cabinets.
I take it those are 6.5" woofers? They look to be built on a standard US 6.5" frame.
Maybe a 30 oz magnet? I wouldn't mind measuring a pair.
A complete guess would be this, but it is not built on a US frame so dimensions would have to be checked,
might be a good temporary fix or perhaps someone could retune the crossover to make them work fine:
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16 minutes ago, ra.ra said:
There have been many hypotheses applying and guessing at suitable re-sealing materials which have resulted in damaged or ruined drivers, and unless/until these materials are documented with results measured over time, my own attempts to re-seal cloth surrounds will remain confidently loyal to the liquid butyl goop that Roy has cooked up and generously shared with this community.
As far as I know Shoe Goop is butyl goop. Someone who needs some might want to experiment.
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I was talking about the one on the left and if you read the thread I talk about removing the grille.
I also have the one on the left that you sent but have not done anything with it.
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I'm fairly certain that Jkent sent me a 12.5 years ago, did it have a buzz or something?
Seem to remember measuring it and reporting T&S here somewhere.
Seems it was the KLH-20 tweeter version that probably has a much stiffer spider for
a higher Fs: http://www.classicspeakerpages.net/IP.Board/index.php?/topic/4238-klh-20-tweeter-dissection/
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Thanks for all the info, it would be great to find out what was used originally.
Save a sample from a blown 12.5 and perhaps a materials person might analyze it someday.
I've been told that Shoe Goo and E6000 are the same product from the same company, no
idea if this might work:
http://eclecticproducts.com/downloads/tds-shoegoo-us-au-nz.pdf
How to dilute it: https://www.rcgroups.com/forums/showthread.php?385740-Thinning-Shoe-Goo
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On 9/3/2019 at 4:03 PM, EddieO56 said:
Do the red x's (or red +'s depending upon your perspective) on the front plate of tweeters from this era indicate which pole is positive?
I think that is true, you can watch the tweeter cone very closely and apply a 1.5V battery to the terminals,
it should move out with + to the positive terminal. I've heard of people putting a 9V battery on this tweeter
and seeing it move a LOT, but please don't do that.
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Was the 12.5 similar to this also?
Open back full rangers like these usually have an Fs of 80 to 120 Hz.
Sealed back Fs would probably be 200 to 500 Hz depending on how Kloss designed the system.
I know, not very specific but if you measure Fs/Fc at 1 KHz something is probably wrong.
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"The thing about the 12.5s and the Philips mids is that they also go to rather high frequencies and the surround if not terminated correctly could mess that up."
I agree.
Is the 12.5 sealed back or did they use a cup behind it?
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About doping the AD5060 that is with the fabric edge I take it?
I'd use a very light coat of a material that remains very soft.
Edit: Don't use Permatex Form a Gasket, JKent wrote this:
- I see a "possible" problem. Our late friend Carl Richards (one of the moderators here btw) did great work but in 2009 he may have still been using Permatex to seal the woofers. That was suggested in the 2007 AR-3a restoration guide but that was a mistake. Turns out Permatex eventually hardens somewhat. The ONLY sealant that should be used is RoyC's butyl rubber solution but that may not have been available in '09. So the real question may be; how to remove the Permatex."
Here are some threads about re-doping tweeters but I don't think that shellac or varnish is the
correct material for edges:
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Next it sounds like you want to re-dope a woofer edge and you want to know the T&S parameters.
My advice is that you don't really need them due to the nature of acoustic suspension speakers.
The first thing to consider is the in box resonance Fc and since the air spring dominates the important
parameter is moving mass which is mainly the cone, VC assembly and a bit of air that couples to the
cone. These do not change. What you need when you dope it is to keep the compliance high.
You could measure the woofer in free air and/or in the box in its old state, then dope it and measure
both again. Fs might change a bit, Fc should change less due to the air spring and all that is really
important is Fc.
The second important parameter is Qts, which becomes Qtc in box this is mainly determined by the
motor strength combined with the resonant system at Fc. If Fc is correct and the VC and motor are
still in spec then Qtc should be correct.
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First question, what are 12.5 drivers, can you provide a link?
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Great info, first I've seen of the test specs, thanks.
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Hope to see you there!
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He was a member of CAS here in CT and he didn't tell anyone about his long battle with the illness.
He is certainly missed.
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Did you check the tweeter fuses?
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Very nice! Did you use a template for the woofer recess?
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I had one SA woofer that had been powerfully overdriven, easy to do with 200+W/ch, with the VC former
hitting the back plate and bending. Here is a thread where I repair it better than new, you might have to
join Audiokarma to see the pictures:
https://audiokarma.org/forums/index.php?threads/small-advent-woofer-repair-some-measurements.819443/
It was easy to remove the cone because the old glue cracks easily pressing down hard on the spider
at the joint.
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The glue work on those old woofers was not done very well back when they were made. Check
them all by applying pressure to lift or move various parts. The gasket, the dust cap, the spider
to voice coil joint, everything.
Here is an example on an EPI-100 but the idea is the same:
Deleted
in For sale / Wanted
Posted
@montyoldboy22 Where are you located anywhere near Connecticut?