DCM Timeframe TF-350 restoration

So, not to be a bummer, but just saying it like I see it and perhaps my example is not totallly relevant but: I've got some 500's that I have compared side by side with many different speakers and they just .... don't ... sound ... better than average. They look fantastic but in the end they are just two way speakers with a small primary driver and an huge heavy impressive looking package.... just saying....sorry

honest opinions are always welcome. Especially since I may be pouring 100 bucks or so into a set of speakers I won't enjoy. Thanks for your input.

I have 2 pair of Yamaha NS-690's, Epicure Model 20's, Polk Audio Monitor 10's, and JBL L46's, all sitting dormant, so I don't necessarily hurt for good speakers.
 
said it before, and say it again, love your avatar, Dr. Morbius.

"Inserting the breakfast pastry!"
"Contact Dr. Jemima on the phone."
"Increase the Flash Gordon noise, and put more science stuff around."
"Recognize me now, Ruth?"

: )
:D Thanks! I'm a Stooges fan too. :thmbsp:
 
Could someone tell me which caps don't need replacing?? I think it's just the pair of 3.3's....correct? Any experience or info on which caps mate best?
I'm restoring a pair of Timewindows and two pair of Timeframe 500s. I replaced every capacitor I could get to. On the TF-500s there are 3 mylar caps hot glued to 3 coils as part of a time delay in the tweeter circuit. Too much effort to putz with. But I did replace everything else, except for the coils. I even replaced all of the resistors in one of the TF-500 pair.

The TF-350s aren't nearly as complicated due to the lack of the time delay circuit.

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DCM Woofer repair

I really enjoyed your restoration posts. I hope you still enjoy them!

I recently got a pair of 350's and will have to replace the foam surrounds. How did you remove the woofers from the cabinet? They looked to be glued in really well and don't want to break the partical board prying them out. Any suggestions?

Thanks
 
Welcome to AK - and welcome to what is known as "Black Death".

DCM used this gunk to seal it's components into the cabinet. Methods vary to get components loose: Heat and a putty knife. Some use a Dremel and carve it out. I'm sure others will give opinions. Luckily, I have never had to fight that battle (yet).

I do think I have read that behind that gunk are a couple of screws (4 maybe) that will need to be removed. If you don't locate them and remove before you try to get the basket loose, you will break the pieces of the cabinet.

Good luck and post pictures!
 
It is horrendous stuff, the black death.
I finally ended up getting things seperated with a pocket knife.
I don't have a heat gun but have a kick a** hair dryer, not sure if it
Helped at all. Good luck.
 
I really enjoyed your restoration posts. I hope you still enjoy them!

I recently got a pair of 350's and will have to replace the foam surrounds. How did you remove the woofers from the cabinet? They looked to be glued in really well and don't want to break the partical board prying them out. Any suggestions?

Thanks

I think I used one of those orange handled pry things. Don't know the proper name for them, but they are usually in a kit, they look like screwdrivers but with evil looking points on the end of them. You can get them most places, most auto parts stores sell them, Harbor Freight, even Dollar Stores sometimes. I just took one of these and carefully pried the woofer up through one of the screw holes.

Lee.
 
Thanks - I've got my tools of destruction ready - dremel tool - check, heat gun - check, assorted knives and screwdrivers - double check.... Hopefully, that should do the job.

I'm also going to attempt to replace the socks on a set of 400's using dark brown instead of black cloth with the help of my wife. She's also stripping the black paint off the ends to stain them. I hope I'm not breaking any DCM rules by going with a different color...

Joel
 
it turns out I was mistaken on the woofers being glued in. I had been looking at a pair of 400's that was covered in black death. The 350's woofer were not glued in at all. I was almost dissapointed:tears:. Re-foaming is progressing and I hope to be listening soon.

joel in Tennessee
 
I picked up another pair of these the other week, but they have the wrong drivers in them, both woofers and tweeters. I managed to find a pair of woofers on eBay, but :( they had been refoamed and they buzz where the voice coil is rubbing on the magnet. I managed to come to an agreement with the seller, he refunded me the purchase price of the woofers. I will re-refoam them, just need to find a pair of tweeters now...

Lee.
 
I picked up another pair of these the other week, but they have the wrong drivers in them, both woofers and tweeters. I managed to find a pair of woofers on eBay, but :( they had been refoamed and they buzz where the voice coil is rubbing on the magnet. I managed to come to an agreement with the seller, he refunded me the purchase price of the woofers. I will re-refoam them, just need to find a pair of tweeters now...

Lee.

The only speaker I've refoamed that still buzzed. I think basket sag leads to VC rub sometimes. I centered and re-centered, but to no avail.

Good luck, Lee.
 
I really do not like those tweeters. I know they are in the TF-600s, which many people on the forum love, but I don't care for them at all. I own a pair of TF-600s and I like the TF-500s and TF-700s much better. I know I am in the minority here.

To my ears, they just don't sound as clear and crisp as the Vifa tweeters used in other early DCM designs. Also, they have a penchant for blowing, hence the glass fuses in the TF-600s and TF-400s.


I am in full agreement on this Doc. I had a pair of 600's and 350's.

While not having the "shock and awe" sound stage of the 600's the 350's "to me" were the winner hands down, the Vifa's were clearly superior being much more accurate and cleaner.

As much as I wanted too I couldn't buy in on the sloppiness of the 600's. Sold them fast and gave the 350's to a good friend who is still enjoying them today..
 
Here is what the later crossovers look like. I wondered if the inductors had been messed with, one of them has what looks to be a piece of copper pipe inside, the other has a piece of square section aluminum around it, both held in place with liberal amounts of hot melt glue. It looked a little Rube Goldberg to me (or his English cousin Heath Robinson), but I saw a pair on eBay that looked identical.

The circuit board is weird, it's very thin and flexible, and seems to flap around due to the lack of screws holding it to the terminal cup.

TF-350-08.jpg

These are the woofers I got from eBay, they look fine, but they buzz when test tones are played through them. It's funny how the eBay seller turned from being almost my friend to someone telling me I need to have the woofers in cabinets, and how they worked fine for three days while they played them. Maybe my idea of "working" is different from his. The fact that the glue was almost still wet when I removed the foams tells it's own story.

TF-350-09.jpg

Lee.
 
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Dang, Lee, how many resto projects you got going?? Been following your AR9 thread as well. Keep up the great work.
 
Here is the problem with the woofers. They both have some degree of cone sag, the picture below shows the worst one. Sometimes, using a test tone or AA battery method doesn't cure this. By removing the dust caps and shimming the voice coil, you force the new foam surround to take the position of the cone and not the other way around. By the way, notice the huge spider these woofers have, it's very large for a 6.5" woofer, maybe that's why these speakers have such good bass extension?

TF-350-10.jpg

Here they are gluing...

TF-350-11.jpg

And here they are completed. Guess what? No more buzzing. I think I will make some of my custom gaskets instead of using the cardboard ones. I made a note on the magnets which way to reinstall them, so the "sagging" part is now at the top, if that makes sense. Maybe in 20 years time, the cone will have sagged the other way, and it will be time for a another refoam?

TF-350-12.jpg

Lee.
 
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Wow, Lee, great job. Wish I had shimmed. New woofer cost me another 35 bucks or so. Glad to know it really wasn't anything I did, I just didn't do enough.
 
Wow, Lee, great job. Wish I had shimmed. New woofer cost me another 35 bucks or so. Glad to know it really wasn't anything I did, I just didn't do enough.

Sometimes that happens. You asked about other projects, I have a pair of Mission 700 speakers (the originals with the white baffle) that I'm refoaming / restoring. I just shimmed both the woofers to install new surrounds, didn't one of them rub when I tested it? Arrrggghhh! I had to cut of a perfectly good new surround, and will try again.

Lee.
 
Sometimes that happens. You asked about other projects, I have a pair of Mission 700 speakers (the originals with the white baffle) that I'm refoaming / restoring. I just shimmed both the woofers to install new surrounds, didn't one of them rub when I tested it? Arrrggghhh! I had to cut of a perfectly good new surround, and will try again.

Lee.

Are you saying you shimmed, and STILL it rubbed?? Boy, that sucks, Lee.
 
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