Whatever happened to DCM's Steve Eberbach? - Page 4

Tracy RainH2o wrote:


No advantage that I could see. Driver, crossovers and cabinets all interact. There is alot of thought and testing in designing speakers, I would think that there is little latitude in design change. Like the saying goes: "If it were easy, everybody would be doing it."

I don't know. Before I was able to get a copy of the TW7 schematic, Steve offered to let me copy the crossover from a SS center that he had. I did not get a chance to look at it. I would assume that the SS center uses the same tweeter as the TF and CX series. The TW7 tweeter is slightly different; the damping circuit values are different. The cross over points might not be the same. There is one on Ebay right now. It may be possible to make it work with some slight modifications. If you wanted to use a TW7 tweeter you would have to rewind the inductor and change the value in the cap in the dampening circuit. If the cross over points are different, then you are looking at changing the cap in the highpass filter and the inductor and resister in the low pass filter that is used in the CX17 crossover. It may be more complicated that that. Defiantly a question that only Steve would know for sure.

Tracy, I over estimated. It's easier to remove turns after you measure the value. Make sure you use the same gauge magnet wire.

You all may remember me looking for replacement tops for my TW-3's. Well, I still need those if anyone has a lead. I have yet to approach a local cabinet maker I know to make new ones. Is there any interest here should he agree to making new tops (and bottoms consequently) in quantity? I'm sure once he's set up it's easy to make more. Let me know.

Anyway, I've come up with an interesting issue which is making me nuts. When my TW3's arrived they'd been pretty shaken up. One of the DCM tags had come off. So my question is, shouild the tag be on the port side or the unported side? I'm assuming they mirror image each other like the speakers do. My understanding it that the ports should be facing outward so the tags should be on the non-port side so the listener can see them. Is this right?

I would also like to get a copy of the original instruction manual if there's anyone that can provide this. If there's a cost involved, please let me know. I can be emailed at JPw50101@yahoo.

Thanks for helping the newbie.

Joe

Joe, the tags go on the inside (unported side).

Here's a link on the TW3 that may be helpful.

http://r.duffy.home.att.net/dcm/

Thank you both, very much!




Joe

I had a chance to talk to Steve and he said they should have been TimeBase subwoofers (Not to be confused with the TB series of subs that DCM later sold. They were shorter that the TimeWindows but much larger in diameter with end caps and also phase linear. They were an add-on to the TWs.

To prove to you all that Steve is alive and well, here is a photo taken at the SMWTMS (Southeast Michigan Woofer and Tweeter Marching Society) meeting earlier today. Steve's on the left and I'm on the right.

Tracy, no, I did not get your email. Please try again.

I also found the new tops on ebay. I've corresponded with the person and have a new set of tops on the way. He seems to be a pretty good guy and I am planning to see if he would be interested in being linked in here or maybe on Bob Hodas' TW3 site. He also has the polyester material for TW1 socks. I have to measure mine and get that to him. I get the impression it NOS stuff he's got. Hummmm....

Jamie, glad to see Steve is alive and well and a pleasure to see a face with the names. Thank you for that. Yes, you can assure him that there are plenty of TW die-hard fans out here, if the way they get snapped up on eBay is any indication! LOL!


Joe

I've got a pair of time windows but don't recall which model they are. I bought them around 1980 and there are no tags or identifying marks on the outside. Only connections for the speakers and a bolt on the bottom that appears to hold the Oak top bottom together. Is there an easy way to tell which model they are short of taking them apart. I'm guessing they are the 1's.

Still listen to them daily and I'm curious after reading this thread.

Thanks
Pete

OK Tracy,

Thanks for the info. I have a very tight anti-spam setting on my comp so I will look for your address if you would please try it one more time? Thanks.

Pete, I would say you have a set of TW-1a's. "The 1a's had a model tag stuck on them down by the banana jacks. The tag was plastic (but looked like metal) and the glue gives up after a while and they get lost. Mine are like that. The original "1's" had vertical moldings down the back and the tag was in between these. So, if yours have no moldings they're probably 1a's. I'm not sure about the oak tops. I've seen both models with that. I think the later 1's came that way but I'm not sure.

Anyway, they sound great regardless.

Joe

Thanks Tracy and Joe.

There is no molding or tag on the back just the 2 banana plugs. After reading through all the earlier posts in the thread it kinda sorta looks like the 1A's were 36" and the 3's are 39 and 1/4 inches tall. Off to find the tape measure.

Thanks again

Pete, the 3's are easy to identify, First, they are coaxial (the tweeters are mounted in front of the woofers). With the 1's and 1a's, the tweeters were mounted under the woofers. You can feel them. Second, they have three pots (dials) located on the top rear of each speaker. From what you described, I would guess that you have the 1a's. Here are some example photos.

I have always wanted that great TimeWindow sound (or at least vintage DCM quality) in an in-wall/ceiling speaker. A while back Steve said in an email to me that he had nothing to do with the in-wall speakers and could not really comment. So, I was thinking of installing either the CX-17 or 27's in my ceiling as I have plenty of space between the joists and the next floor to accept the boxes. Of course, the CX's have ports in the back. Do any of you have a suggestion as to how I should modify the CX's to make them work in this application? Do I extend the ports with some pipe to wrap them to the front to go out another opening in the ceiling into the room; plug the ports with foam; or leave the ports open to the space between the ceiling and floor? I don't think I could simply modify the cabinet to move the port opening to the front instead of the back. If you have ever removed the speaker terminal from the back and looked inside you will find that it is not just a hollow box, along with the port tubes there is a vertical baffle stuffed with fill. The air path from the driver to the port is not simple and must have a purpose. What was Steve thinking? Do you know if Steve designed the CX's? For my application, maybe I should be looking for two SurroundScape centers with their sealed enclosure, but they are so hard to find. Maybe there is a way to copy the cross-over in my SS center and build a sealed box with CX-17 components to fit my walls and ceiling.

Does anyone have thoughts regarding the benefit of replacing the spring terminals on the CX's with binding posts? Does it really make a difference for signal transmission versus banana plugs? After getting a headache reading gobs of info about speaker cable it is rather interesting that the wire used in the speakers themselves is like 16 awg wire and the conductive path in the crossover itself is many times smaller.

By the way, thanks for the photo of Steve. Why can't we scrape up a few $$ and have him design a new speaker and start a company? How naive am I?

Thanks Jamie, They must be the 1a's. No pots to adjust and I can feel what must be the tweeters below the woofer.

If you change the length of the port tubing you will change the tuning of the box. And yes, the CX series is Steve's design. You could possibly reproduce the SS Center box and use the CX drivers. The crossover could also be reproduce. If you email me some detailed photos, I could check with Steve. I can also ask him about moving the port to the front.

OK, a little off topic, but, is anyone aware of any other TW sites or blogs that I could look at? Is there another thread on this site that I haven't seen?

Joe

Someone wrote the following in an ebay question regarding a TW for sale. "I just want to let you know that your speakers are not 1a, they are just model one! the 1a dont have foam and use bifa drivers that fix a low freq. flow, your speakers have phillips drivers, and are less expensive than 1a!" Besides the bifa, which probably means vifa, that some 1a's also had foam during the cross-over from 1 to 1a, and I don't know what a low freq. flow is, is there any truth to this statement? Of more importance, are the drivers on the 1a interchangable with the drivers on the 1? My drivers are currently fine on my 1's, but having spares might be prudent.

Thanks

Did Steve have anything to do with the KX Series II? Is he really a fan of horn loaded tweeters that the KX used?

Can we come up with a list of speaker models, DCM or otherwise, that Steve had design input and seal of approval?

It would be really great to have a brief description of why he chose a particular design. The TF's with their broad and flat front versus the narrow front of some current, non-Steve (I presume) DCM models. The Acoustic Lens concept. The anti-defraction screen or is it really just a coax mount. Does the screen produce thousands of baby woofer sources, one for each hole (you can tell I don't understand acoustics and the effect that a screen has on the wave front)? If there is a benefit beyond a coax mount, then why not cover the other woofers with a screen as well? The PrestiDigital electronic time equalization found in SS and KX Series II. What does that mean? Why he went with poly cones in the later woofers versus paper in the TW1.

Thanks

Sydneybird

I'll try to answer some of you questions to the best of my knowledge from what Steve has told me in the past.
I agree with you that I have seen some early TW1a's that still used the foam covers. Driver interchangeability is a guess.
Steve did not have anything to do with the KX series and I don't think he's a fan of horn loaded tweeters because it does not show up in any of his other designs. Although DCM could have made use of some of his technology in their later designs
Steve's connection with the company ended around 1999 when Mitek took over. His designs would include all of the TimeWindows including the SurroundScape, TimeFrames, Macrophone, TimePieces, HalfTime, FullTime Base, TripleTime, CX series, VLS-2, and possibly the OW-1, OW-2, and a few subs. DCM has been reusing some reincarnation of some of these names like the Time Frame Evolution which has nothing to do with Steve.
Steve told me that marketing wanted a floor standing version of the CX series. That's how the TimeFrames came about.
The screen does more that just hold the tweeter. It smoothes out the frequency response. I would guess that it is not need on the woofer because of the lower frequencies. A Japanese company made the poly cones special for DCM and the drivers were assembled with these cones by another vender. DCM then could change driver venders for assembly, but keep consistency in their speakers. According to Steve, these cones had a very flat response, and they were not locked into one driver vender. To show how good they were, that same 6.5 driver that was used in the CX and TimeFrame series was used in Steve's signature series TimeWindow Sevens that sold for $3,200.00 a pair in 1999.
I hope this helps, if anyone has anything to add, please do so.

Thanks, Jamie. I much appreciate your replies.

I know the TW7's are Steve's favorite but I would love to hear where he places the TF-2000's on his list. I bought a pair of the 2000's just to say I have the top of a model line with Steve's fingerprints on them. I can't complain, they sound great!

I just acquired 4 CX-17's just for the heck of it and possibly using them in ceiling/wall as previously posted. I haven't tried plugging the port to see how that affects the sound. Without having a spectrum analyzer handy I wouldn't be able to hear the difference except for the low frequency extension. They are very nice sounding with surprising bass as to be expected a la Steve's transmission line. I wouldn't really consider them bookshelf speakers as they need some distance from the back wall that you can't get if you placed them on a bookshelf. I'm just missing the CX-07 (acoustic suspension) to fill out my CX collection. Is the CX-07 anything special? I didn't think the CX Center (acoustic suspension) was a wow as compared with the SS Center (acoustic suspension). Just for fun I set the CX-17's on my desk to listen while working at my PC but the highs are way too in-your-face at only 3 feet distance and with the back within a few inches from the wall gave too much boomy bass, of course. But they are great a 2 ft from a wall and listening about 7 feet away.

Not all CX-17's are created equal; maybe the others as well. I have a set with s/n of 9412/9413 with paper cones on the woofer and 33786/33787 with poly. With tweeters disabled, the woofers really sound the same to my untrained ear. The disassembly of the CX-17 drivers came about because the tweeter on the lower s/n set are dead. There is a brown ooze on the cone and on the screen. Maybe this is the ferro-fluid stuff? I disassembled the tweeter from the back and there was a dark brown liquid between the cone and the magnet. Now I need to look for some new tweeters. The tweeters on the earlier s/n have a number 040D0301 8 ohm 40W, and the later s/n of 011D0202 8 ohm 40W. Is there any hope in finding replacements?

I just dug out my OW-1 or 2's (I think they are 1's but can't really measure woof, about a 5.5 inch hole) as a comparison with the CX-17's as desktop (wall mount) speakers (headphone jack to a HK integrated amp). Where I had to decrease treble substantially on the CX-17's, I had to increase treble to the max for the OW-1's. OW-1's have little bass as expected from their acoustic suspension design. I added a CX-17 (with broken tweeter) on the floor under the desk driven by a subwoofer amp to complete below 80 Hz and they now sound very good.

I took the SS center cross-over pictures; I'll be emailing to you soon.

Hello

I am French and I have time window seven I seek the wiring diagram to repair bus broken down woofer

thank you

thierry.beuzeboc1@free.fr

We should make a list of interesting Steve-designed speaker links. If you post or email them to me, I'll paste here. Here's some:

http://r.duffy.home.att.net/dcm/

http://www.***************.com/htsth...51/type/thread

http://forum.audiogon.com/cgi-bin/fr...&openfrom&60&4

http://www.polkaudio.com/forums/arch...p/t-26006.html

http://forums.audioholics.com/forums...p/t-13114.html

http://www.audio-ideas.com/reviews/dcm.html

http://www.audiokarma.org/forums/arc...p/t-75978.html