SDA 2.3 Crossover Problems

Gill3896

One of the coils on the crossover board got hot and melted it's plastic. I have checked all the resistors and caps on the board with a meter and the Schematic and they are ok. I need to replace this coil (.4mH) I don't have much to go on as far as specs (type, pwr rating). Could use a replacement crossover if anyone has one. Any advise ???? Thanks.

Gill3896

pitdogg2

what are you running these with? Common ground? IMO it is just a little weird to have gotten the inductor that hot yet everything else is OK. something is wrong somewhere and needs to be figured out before you fry something else.

Mr. Bubbles

This could have easily occurred due to a cold solder joint on the inductor, and not likely a problem with the inductor (though inductor problems are possible the cold solder joint is much more likely). To replace the inductor you also need to know the DCR of the inductor or it will sound different from the other channel and not operate as designed. Someone else on the forums may be able to tell you the DCR. If not you may need to pull the same inductor from the other channel and have it measured properly to determine the DCR.

for what its worth the inductor in question may still be useable, but personally I wouldn't want to use it.

gimpod

pitdogg2 wrote: »

what are you running these with? Common ground? IMO it is just a little weird to have gotten the inductor that hot yet everything else is OK. something is wrong somewhere and needs to be figured out before you fry something else.

Ditto. Inductors don't get hot and melt just for the fun of it. What 2.3's do you have the TL or non-TL version and which inductor was it the one near the top of the board or bottom. Pics of the top and bottom sides of the board could help.

Gill3896

Thanks for thew replies. It is the bottom inductor and it is cooked and unusable. I'm using a QSC RMX 850 for power. I pulled all other components dealing with the high end off the board and they all ohm out. There are 2 750pf's on the board that I couldn't varify due to my meter capabilities. I would like to replace the whole board at this point just to be sure. I have the non TL's.

F1nut

I'm using a QSC RMX 850 for power.

Well, there's part of the problem.

I would like to replace the whole board at this point just to be sure.

Contact Gimpod, he sells new boards for your speakers. You should also replace all the caps and resistors.

As for the cooked inductor, you'll need to have the good one from your other board tested to find out the proper values. Then you can shop around for a new one. Actually get two, one for each crossover.

Gill3896

Why is the QSC a problem? Do the new boards have the components installed?

Schurkey

Gill3896 wrote: »

Why is the QSC a problem?

Pro amps are not in vogue on this forum.

Gill3896 wrote: »

Do the new boards have the components installed?

Nope. You get to populate the board as a DIY project--or--I suppose you could pay someone to do it.

F1nut

Gill3896 wrote: »

Why is the QSC a problem?

Get a good home audio amp and you'll know why.

Gill3896

I have a vintage Carver amp. TFM-22. Would that be better?

Schurkey

Try it and see. Plenty of older amps are in need of service due to failing capacitors or other problems. Carver is well-liked on this forum (I've not listened to one in at least twenty years) so it might be worth the trouble to send it to a service center for a check-up and freshening.

http://ritasvintageaudio.net/

There may be other service options, that is the one I'm aware of. Apparently, it's a joint venture between Bob Carver and one of his former employees.

gimpod

Gill3896 wrote: »

Thanks for thew replies. It is the bottom inductor and it is cooked and unusable. I'm using a QSC RMX 850 for power. I pulled all other components dealing with the high end off the board and they all ohm out. There are 2 750pf's on the board that I couldn't varify due to my meter capabilities. I would like to replace the whole board at this point just to be sure. I have the non TL's.

Have you found the source of the problem yet, I suspect it's your amp from the schematic it look like it's a non-common ground amp as I believe most pro amps are although I could be wrong ether way check you amp to make sure it's a common ground amp SDA's require this or bad things will happen. If that amp is non-common ground that is most likely the source of your problem also I would check all the drivers and tweeter to make sure none of them got fried also. You really need to find the source of the problem before going forward with any repairs.

The 0.4mH inductor that you need I may have a stock one I could snag from my secret SDA parts stash the only question is what gauge is it, I suspect it's a 22 gauge as Polk used a 0.4mH 22 gauge inductor in a lot of the 4th and 5th generation SDA's unfortunately the schematic for your 2.3's don't have the wire gauge marked for the inductors in the high pass section.

Joe08867

The QSC is common ground. All the RMX series are. I would still look into another amp though as the sound quality on the RMX series is no where near as good as even an entry level home amplifier. The QSC stuff is made for quantity not quality..

BY the way I own the RMX 2450 and love it for subwoofer duty but the fans are super noisy.

Gill3896

I would be very interrested in the inductor. All other speakers chk'd ok. Swapped good xover to check. Running my whole system with Pro Amps. Left over from the old band days. I have a Yamaha RX-V3000. Would it be enough for 2 SDA 2.3, 2 SDA II and 2 JBL 4311,s all in 7.1 setup?

Schurkey

Gill3896 wrote: »

I have a Yamaha RX-V3000. Would it be enough for 2 SDA 2.3, 2 SDA II and 2 JBL 4311,s all in 7.1 setup?

THIS RX-V3000? Yamaha claims 6.1 channels in one place, and then lists power specs for eight channels. 6 X 100 plus 2 X 25.
http://usa.yamaha.com/products/audio-visual/hifi-components/stereo-receivers/rx-v3000_black__u/?mode=model

No long-term power specs for 4-ohm use. "Dynamic" specs for 8/6/4/2 ohm use. At least the thing probably won't wet the bed when connected to "4-ohm" speakers.

As long as it's common-ground, it should work fine especially at low to medium volume levels. Most receivers are common-ground...but it wouldn't hurt to spend five minutes with an ohmmeter.

I think you'd be better off powering the main speakers with your Carver, especially if you have it freshened.

Gill3896

Gimpod, Still interrested in that inductor. Find one in your stash?

gimpod

Gill3896 wrote: »

Gimpod, Still interrested in that inductor. Find one in your stash?

Yes I did, Also got your email. Shoot me your address and I send to you if I can find a small enough box for it.

Shameless plug alert! :redface:
If your interested in a set of boards I could send it along with them.

Gill3896

Brad L. Gilles
668 Ft. Couch Rd.
Pittsburgh, PA. 15241

Boards loaded? Would love any help.

Found out the problem...was running 1 side with a Nady 1100 bridged which was not common grounded, the other side was the QSC bridged and common grounded. Know better now.

F1nut

Am I reading this right, you're trying to run bridged mono blocks and on top of that using different amps!?! Forget the one that you say was non-common ground, they automatically became non-common ground when you configured them as mono blocks.

Word of advice, never post your name and address on an open forum. Ask a mod to remove it.

Schurkey

Gill3896 wrote: »

Found out the problem...was running 1 side with a Nady 1100 bridged which was not common grounded, the other side was the QSC bridged and common grounded. Know better now.

No such thing as "bridged and common grounded". Bridged, by definition, CANNOT be common-ground.

If you're using two monobloc amplifiers, they have to be connected negative terminal to negative terminal to be common-ground. Try that with bridged amps, and you'll probably let all the smoke out.

Thus the popularity of the AI-1 interface including the Dreadnought style.

F1nut

If you're using two monobloc amplifiers, they have to be connected negative terminal to negative terminal to be common-ground.

Never do that without checking with the manufacturer first.

Gill3896

Thanks for the advice. I'm new at this.

drumminman

Gill3896 wrote: »

Thanks for the advice. I'm new at this.

Hang in there and keep asking questions - we were all new once.

Gill3896

Still waiting to hear from GIMPOD.

F1nut

He's under the weather. He also said he was mistaken about having the proper value for your crossover.

Gill3896

I was so excited. Darn! I have been using a Cerwin Vega as a replacement. Not the same.....Help, I need a SDA 2.3 crossover.

drumminman

I was so excited. Darn! I have been using a Cerwin Vega as a replacement. Not the same.....Help, I need a SDA 2.3 crossover.

Oh the horror. . . .the horror :eek:

F1nut

Well, you don't need a crossover, you need an inductor. As I stated, take the good one from the other crossover to a good shop that can test it. Then, you'll know what to go shopping for. It would be best to replace the good one as well as the cooked one, so they balance match.

Gill3896

don't have a good local electronics store. Any advice?

VR3

Send the crossover to me... (The good one) with tape on the inductor you need measured...

I will get the values for you and send you a link to a supplier.

Service is no charge, you just pay shipping to and from.

Email for more info - Vr3Mods@gmail.com

Thanks

naturallight

Well..when you get the speakers fixed....sell off the Nandy amp first off. You can use the QSC..just put it back to stereo mode. Not the best amp..but if you have no money to upgrade...it will work. What you need at min an Adcom 555 poweramp...probably a Carver.

I have run stuff on a QSC amp, but a GX5 which uses a class H power system. I've run this on a set of RTi 12's and a set of SDA1c's....

It has massive power, but is bone sterile...it's not real pleasent to listen to on the RTi12's..on the SDA's..due to the SDA effect..is not nasty..but again not great..but you can get by with it, until you can afford a better amp.