Turbosound---changing CD-102 to CD-103---new crossover or just screw-on adapter?

Alex Connell

May 4, 2012
Charlotte, NC
I want to keep my Turbosound TMS-2s alive and kicking as long as possible. And since they are paid for and sound is more a avocation than a vocation for me I want to make sure that I can do it as cheaply as possible and try to avoid unplanned expenses. Recently, I have been trying to get a feel for the availability of replacement diaphragms for the CD-102 (part # RD-102) and recone kits for the 10" Turbomid from my cabinets (LS-1001, recone is RS-1001), and the 15" Turbobass (LS-1503, RC-1503).

Looking at the component map, http://www.turbosound.com/upload-files/File/technical/component_map/compmap.xls, it would appear that the CD-102 is flatly not available (same for the LS-1001). The RD-102 do appear to be available in a few spots but they are not at all cheap.

It is my understanding that later on in the production runs of the TMS-4, TMS-2, and the TMS-3 Turbosound switched over to the CD-103, which is apparently a re-badged EV DH-3. These compression drivers appear to be far, far more available and far, far more reasonably priced that the replacement diaphragms on the CD-102. The CD-102 is a bolt-on driver, while the DH-3 is screw-on.

Per the component map and my reading elsewhere, at some point Turbosound marketed an "upgrade kit" (Part No. 15268) to replace the CD-102 on the TMS-4 (and on the TMS-2BP/T4) with the CD-103 driver.

On the CD-103 models of the TMS-4 the crossover was a PX-5 v.v. a PX-4/111 (CD-102 models). On the CD-103 models of the TMS-2 it was the same PX-5 v.v. a PX-2 (or 2-A). For the TMS-3 with the CD-103 it was a PX-3B v.v. a PX-3A for the CD-102.


Now that I've laid the groundwork (or at least some of it), I'll ask my real question: can any of the many folks on here that have built their companies around Turbosound over the past 20 years or more comment on what was included in the upgrade kit? I saw a thread from earlier this year where the speakerforums folks seem to suggest that this change over could be accomplished by merely purchasing a $6.50 adapter to change the bolt-on compression driver to a screw-on. That does not make sense to me given that the CD-103 models invariably employed a different crossover than the CD-102 models (even if it was not the same between the 2, 3, and 4). And of course, per Turbosound, the PX-5 is not available. I would like to keep these speakers as close to their intended specs as possible and I do not want to go down the triamp route (though ultimately that could in the long run prove cheaper). Did these upgrade kits include a new crossover or crossover components? It is not clear from the component map what was included in the upgrade kit and no crossover change is mentioned. Forgive my ignorance on this topic. I have had these speakers for about 5 years now, but they are very nearly as old as I am so I was not exactly in a position to know what was really going on with them in the late-'80s and '90s when they were a contemporary product! Is anyone aware if these upgrade kits are even available and if so whether or not they are prohibitively expensive?

Any comments or information would be much appreciated. If anyone has a bin of pieces left over from these cabinets' glory days please let me know as I might be interested in acquiring some spares.

Steve Payne

Jan 16, 2011
Richmond, VA
Re: Turbosound---changing CD-102 to CD-103---new crossover or just screw-on adapter?

I made this transition on 16 TMS4s back in the day. The upgrade kit consisted of a bolt on to screw on driver/horn adapter, CD-103 (i.e., EV DH3) driver, and a complete input panel with new crossover attached. There was nothing different about the input panel, but Turbo chose to do it this way to make it a "plug n play" upgrade. Other wise quite a bit of soldering would be required removing the old and installing the new crossover, along with the possiblity of mis-wiring with potentially ugly consequences. I would bet big money that there are no kits available, but I am sure Turbo could furnish you with a circuit board layout and component map if you wanted to roll your own crossovers (or have someone experienced, like Too Tall, build some up for you). The CD3 upgrade was a very big step up in high frequency performance and reliability for the TMS series. At the end of the day, it is a 20 year old design with quite a few limitations by today's standards. You'll have to ask yourself just how much trouble is it worth to keep them kicking. Triamping these boxes was a very common practice in the days of yore. It might be the easiest solution. Good luck.

Robert Knoll

Jan 13, 2014
Re: Turbosound---changing CD-102 to CD-103---new crossover or just screw-on adapter?

Good Day,

I have all the original drivers from 1980. contact me