DCM Time Frame TF-350 Tweeter help

[Blake B.]

Hi everyone--long time lurker, first time poster. You all have certainly helped me in my audio decision making in the past, and for that, I thank you.

I recently picked up a pair of DCM Time Frame TF-350's on Craigslist. Unfortunately, I wasn't able to test drive them, but the seller reassured me that the woofers were recently re-foamed and they sounded great. I got home and hooked them up to my Pioneer Elite VSX-29TX receiver, popped a CD in my Denon DCD-590 and let em' rip. They sounded decent upon first listen but I noticed a difference in sound from the right and left speaker. Upon closer listen, the tweeter on the left speaker is not firing. I'm guessing it's blown?

I'm pretty competent with car audio but as I just moved into my first actual house and don't have to worry about neighbors complaining--this is my first real adventure into home audio.

Does anyone have any thought on what I should get to replace the 3/4" tweeters--or would there be any other issues I need to check for? I'm guessing I should probably replace both at the same time? Is it a terribly hard process? Like I said I'm fairly familiar with automotive audio systems having had a few myself, but I'm a total noob when it comes to home audio. Is the Pioneer a competent unit to power the Time Frames?

Any help you guys have I would really appreciate! Thanks in advance!

 

[icenine]

https://www.parts-express.com/peerless-by-tymphany-d19td-05-3-4-poly-dome-tweeter--264-500

One of the reviewers says it is a close replacement. I bought one for a pair of 700s once.

 

[Alan G.]

I just went through this with my 350s. Left tweeter blown. It was advised to watch that auction site for an original Vifa replacement, as they were custom ordered by DCM. Trouble is DCM started using Vifa T19TD-07s (8 ohm), later changing to T20TD-07s (6 ohm). Better to know what you’ve got. Not me. I bought an original (used) T19 only to find out mine had the T20s.

Removing the sock was relatively easy for me. As advised I went from the bottom and rolled it up. Anyway, I replaced the bad tweeter with a good one, although I had to slightly alter the crossover. It worked!

I’d highly recommend seeing what you have. I was told those Vifas do show up. Took three weeks for me.

 

[loose ends]

If it's the same as the ones in my tf 600 then I have one. I did use the ones from Parts Express and I replaced all. They even sound a little better than the originals. Let me know if you want it.

 

[BilboBaggins]

I agree with above. Check to find out the tweeter. They used VIFA tweeters but with different variations. I actually temporarily put in a pair of 1 inch soft dome VIFAs in mine and that allowed me to increase power input. I found the highs and minds were better better this way than when I got the replacement tweeter. But I am the kind that needs to leave things original. If I ever build my own speakers though, that is a whole nuther story!

I found that if I knocked the oaken top off, I was just able to roll down the sock just low enough to get to the tweeter. I used fabric glue before putting the oak top back on. Worked very well!

 

[Alan G.]

Oh, yeah...if you have the wood back with all the screws, you’ve got the T19s. Early version.

Made sense to knock the top off and peel the sock down because the drivers are near the top. Then I was told to do it from the bottom, held by the kickstand bolt and two screws, simply because of the wedge shape of the speaker. No stretching of the material that way. It was pretty easy. You do have to unscrew and pull out and disconnect the connection point/crossover, though.

Personally, I’m not sure what using a different tweeter would do. Your choice.

 

[Blake B.]

Thanks folks for the help. Just knocked the top off of my speaker and rolled down the sock and took a few pics of what I found. Looks like an Infinity Polycell tweeter was in there (902-6758 72630-01) a 1" rather than the standard 3/4".

Looked it up and it looks like it's an 8 ohm tweeter. Would I be good going with the Tympany Peerless tweeter that icenine recommended?--As that's a 8 ohmer as well. Or would there be any major benefit from going with a 1" tweeter instead

 

[Alan G.]

Oh, my. Now you don’t know what’s in the other one. When I was asking the same questions as you, I was told by people who had more experience than I do to replace with original; that the crossover, the woofer, the custom designed tweeter were part of the desired whole. BUT, if you ordered a couple of those Peerless 3/4” replacements, at least you won’t be way off, won’t be out too much money and, who knows, maybe you’ll be just fine.

BTW, I’ve read many accounts of DCM blown tweeters which makes me think they were simply overdriven. I run mine with a vintage Pioneer SX-737, rated at 35 watts. I can’t turn the volume control much higher than 1/4 of the way up. It’s plenty loud! These are fine sounding speakers.

Whatever you decide, please let us know the results. And welcome to AK!

 

[Blake B.]

Thanks Alan! I went ahead and de-socked the other speaker and that had the same Infinity tweeter as well. I went ahead and ordered a pair of those peerless tweeters to replace them. The only thing I'm concerned about now is powering these speakers. My two current options are my Pioneer VSX-29TX (120 watts per channel) or my Denon AVR-E400 (90 watts per channel). If I like to play my music at a decent level, will these two options be overpowered? Should I look into getting something lower powered to run these?

 

[Alan G.]

I wish I could answer that. Unless you’re trying to fill a huge room, I would guess that by not cranking them anywhere near distortion, you’re probably fine. Hope somebody who knows will pop in.

 

[bigaltx24]

I usually run my TF350s on a Denon PMA-757 (80 watts per) and I have run them on a Carver M1.0t (200+ watts per) and never blew a tweeter. You'll probably blow tweeters easier with a low power amp than a higher powered amp as the lower power amp goes into clipping easier when trying to play loud.

 

[-reverb-]

The Vifa D19TD-05 is a good replacement. Oh, and those Polycell's can bring decent coin over on that big auction site so you may be able to recoup some of your investment if you are so inclined.

The inner layer of material of your TF's looks to be disintegrated - a normal thing. Much like foam surrounds, it turns to dust after a while. Replacement is not that difficult or expensive, but it's a fiddly process. Headliner material from the local fabric store seems to the be the choice for replacement. leesonic had an excellent thread here on AK to restore his TF's - so did AK member ssouci. I followed their lead with a thread of my own when I restore a pair of TF 2000's. Do an AK search and you're sure to find them.

 

[robitaille03]

If I may jump in on this thread with a slightly different problem ... I have a pair of DCM TimeFrame TF500s that have sounded great since I picked them up a few years ago. BUT, I brought home a new preamp and amp combo a few weeks ago and soon after noticed that the left tweeter was not working. I thought I blew it, because when powering up the new combo, I had a loose connection that sent some loud crackling through the speakers. I ordered a new pair of the Peerless by Tymphany tweeters, put the new one in, and still no sound. Took out the crossover, and noticed that the 12V 1.4A bulb in the tweeter chain was blown. Couldn't find an exact replacement ANYWHERE. Settled on a 12V 15 watt bulb of a different connection style but soldered it in. Fired up the system and the tweeter is working, but the volume of it seems to vary up and down. I have no idea what can cause this, other than something with the bulb. Any thoughts on this? If it is the bulb, I am afraid I will have to trash them because I searched everywhere and could not find an exact replacement.

 

[-reverb-]

You can use a piece of wire to jumper around the bulb - just remember that without the bulb, you have no protection from over-driving the tweeter (that's what the bulb is for).

The replacement bulbs are available. AK Member dgwojo usually has about any type of bulb you would ever need. You can "Start a Conversation" with him and ask. If he can't help, check the auto parts stores. What you are looking for is a 12V 1.4 A welded filament bulb. These are (were) used commonly in overhead interior lights for automobiles. Yo DO need to make sure the rating of the new bulb matches the existing bulb.

Good Luck!

 

[leftfielder]

Another place to get bulbs could be this guy. I bought some glass fuse type lights for my Nikko 6065 receiver and evidently all this guy sells is bulbs and fuses.
Vintage Elecrtronics--Bob Toepfer--www.vintage electronics.net

No Affiliation just bought some fuse bulbs..... Lew

 

[robitaille03]

Great, thank you both for your suggestions, I will try them both!

 

[robitaille03]

An update: AK member dgwojo suggested the Eminence PX tweeter protection lamps from Parts Express (link). They arrived today. They are soldered together in pairs. I unsoldered a pair and soldered one into my crossover. All is well! Thanks again, all, for the help.

 

[Blake B.]

Appreciate the help guys. I ended up getting a pair of the suggested Typhany tweeter and swapping both the Polycells. Not a hard process. I knocked both the top and bottom trim pieces off and removed the sock--as Reverb said above, I wanted to clean up the disintegrating layer of fabric. I went to my local Jo-Ann, picked up some thin speaker fabric for cheap. I lightly sanded off all the remaining crap from the inner layer and cleaner 'er up pretty good. Used some Locktite adhesive spray and threw on the new layer of inner fabric. Reinserted the woofers and new tweeters, socked them back up and crossed my fingers. Bingo! They sound fantastic now--thanks for the help!

 

[-reverb-]

Outstanding work! They look fantastic.