Blown reQuest woofer

[Spike]

Trouble in paradise!! I noticed during my listening session today that bass was quite anemic so I went to investigate. I thought that the bass contour switch was knocked to -4db by accident. What I saw was the black spade had slid off and was stuck to the red terminal!! There was NO sound coming from this woofer. I turned everything OFF, connected the spade terminals back to their correct positions and turn everything back on. Now, there's sound coming from the left woofer, but it's not as clean as the right one. There's a scratchy sound coming out from the left woofer so I am pretty sure that the woofer is blown. I am going to inspect the board as well to see if the bass crossover is blown. I did a search for replacement reQuest woofer and saw this thread Martin Logan Request woofer but I cannot locate the correct woofer at Parts-Express. Is there an updated part number for the Eminence 12" woofer? I will give ML support a call in the morning to see if I can order the replacement speakers. While at it, I am thinking to upgrade the components on the boards as well. Any help or tips with the blown woofer will be greatly appreciated. Thanks in advance.

 

[roberto]

Hola Spike, that's bad news. We do know hoy you do care about your sound system. Having a short at the bass section, your amp could had suffer with this too. The description of the sound problem, is like the woofer's coil is out of position, and it is lean to the magnet, making this odd scratchy sound. I do know that ML has in stock the replacement for it. Again, we feel sorry for that!
Regards from Costa Rica my friend!.

 

[Spike]

Thanks Roberto for the quick reply. I hooked up the suspected amp channel to another speaker and I got clean sound on this channel. It does not seem like the amp is damaged, whew!! Now, since I am going to be mucking around with the internals, the big questions are:

1. Do I replace with the stock woofer or do I upgrade to better woofer(s) with the same parameters?
2. Upgrade/replace the 19-year-old capacitors on the bass board?
3. Upgrade to better step-up-transformer?
4. Anything else I should consider?

Thanks for your help

 

[roberto]

Spike, I do know about your skills in electronics, and then why don't you get a capacitance test meter. This will allow you to check the exact capacitance value of each capacitor. So, if they are OK, why to bother changing them?

On the other hand, better woofers, will not make your Request to sound better. To get more of them, you must change the speaker's cabinet chamber, and you know this. With much due respect, I will let the Request as it is!. It is a wonderful sounding speaker with a superb mid-range, and one of the best still over the planet. If you want deeper bass, why not add a the new BF-210 sub? This sub is very easy to match with any ML speaker model, and really sings beautiful too.

Getting back to the bad woofer, I will replace it with the ML suggestions. If they say, it is better to replace both, then there you go. Regards!

 

[Spike]

Thanks Roberto, for the no-nonsense response to bring me back to reality!! I whole-heartedly agree that if things are not broken, don't change 'em. I talked to ML support and found that it a replacement woofer costs ~$350 each. I've also talked to Eminence and found that the custom designed woofer for ML is no longer in production, the closest model in stock is the LAB12C: Eminence LAB12C 12" woofer
Reviewing these T/S parameters against the stock ML one, I noticed that VAS & CMS are lower for the new Eminence, indicating higher stiffness vs. the stock ML. MMS (mass of cone, coil & moving parts) is higher for the new Eminence (almost double) indicating the heavier magnet. Efficiency is lower 88db vs 91.6db for the older model. Purely from this spec, it does not look like the new Eminence will be a drop-in replacement for the reQuest woofer. Am I way off base or is it still within operating parameters? The new Eminence LAB12C is half the price of the ML replacement, $175 each!!

 

[Tosh]

Thanks Roberto for the quick reply. I hooked up the suspected amp channel to another speaker and I got clean sound on this channel. It does not seem like the amp is damaged, whew!! Now, since I am going to be mucking around with the internals, the big questions are:

1. Do I replace with the stock woofer or do I upgrade to better woofer(s) with the same parameters?
2. Upgrade/replace the 19-year-old capacitors on the bass board?
3. Upgrade to better step-up-transformer?
4. Anything else I should consider?

Thanks for your help

1. There are likely newer replacement woofers out there worth considering.
2. If you want to keep the passive xo, then yes, replace the electrolytic caps.

4. Go with an active xo for the bass! You will need a separate bass amp, but then the efficiency and impedence of the new woofer don't matter...

A difference in efficiency (sensitivity) of almost 4dB is going to be a problem with the passive xo. That's LESS than half power....(edited to say that since you're already bi-amping, you can adjust the bass level to suit...)

 

[FoxMulder]

You can have the blown woofer fixed. Contact Bill Legall from MillerSound. He is the BEST in the business. He repaired a blown, full range driver for me that everyone else said couldn't be done and it was custom made and the manufacturer had gone out of business. It came back PERFECT! Bill's the man and it will cost much less than the alternatives you are looking at.

http://millersound.com/about.htm

 

[Spike]

FoxMulder, Thanks for the referral to MillerSound. I emailed Bill and he responded with very reasonable cost of $170 to repair a pair of woofers. The issue comes to shipping these heavy woofers from NorCal across country to Pennsylvania!! $90 ground each way! Yikes. Does anybody know of any reputable speaker repair technicians on the west coast?

Thanks in advance,
Spike

 

[#ZERO]

The companies listed below are also well known for carrying a wide range of loudspeaker replacement parts as well as reconditioning services and may be able to assist with your service needs:

Advance Sound
1201 Hilton Rd.
Knoxville, TN 37921
865-558-5770
www.advancedsound.com

Audio Lab of Georgia
3611 Clearview Place
Doraville, GA 30340
770-455-0571

Bronx Electronics and Prosound Co.
3382A Boston Rd.
Bronx, NY 10469
718-515-9213

Central Florida Speaker Repair
714-716 W. Smith St.
Orlando, FL 32804
407-423-3566
www.centralfloridaspeaker.com

The Circuit Shop, Inc.
3716 - 28th Street SE
Kentwood, MI 49512
800-593-0869

Consolidated Audio Technology
130 Cannonball Rd.
Pompton Lakes, NJ 07442
973-831-7500

Lil' Peanut Productions
735 N. Lynhurst Dr
Ste B
Indianapolis, IN 46224
317-536-1819
www.lilpeanutproductions.com

Loudspeakers Plus
450 S. Spruce st.
Unit G
Manteno, IL 60950
847-963-0725
www.loudspeakersplus.com

Orange County Speaker
12141 Mariners Way
Garden Grove, CA 92843-4023
800-897-8373
www.speakerrepair.com

Parts Express
725 Pleasant Valley Drive
Springboro, OH 45066
800-338-0531
http://www.parts-express.com/speakerrepaircenter/index.cfm

Simply Speakers LLC
2826 23rd Ave N
St Petersburg, FL 33713
727-571-1245
www.simplyspeakers.com

Sound Check
917 N. Irwin Ave.
Green Bay, WI 54302
920-435-2525

The Speaker Exchange
8217 North Nebraska Ave.
Tampa, FL 33604
800-849-6972
813-237-4800
www.speakerex.com

Speaker Works
3003 West 11th Ave. #288
Eugene OR 97402
888-244-8058
www.speakerworks.com

Tri-State Loudspeaker
650 Franklin Ave.
Aliquippa, PA 15001
724-375-9203
[email protected]

 

[Spike]

#Zero, Thank you for the extensive list! I will definitely contact some of those on the left coast in order to keep the shipping cost down.

 

[HG5150]

I just emailed MillerSound and WOW, instant reply and 85.00 to repair my blown ML SL3 woofer.

 

[FoxMulder]

HG5150...Bill's the BEST. You will not be disappointed.

 

[Tosh]

I just emailed MillerSound and WOW, instant reply and 85.00 to repair my blown ML SL3 woofer.

Replace or recone as a pair.

 

[JonFo]

^^ +1, if updating drivers or reconing, always do it as a pair.

Spike, if you can get them repaired, than that would be your best bet. And if in there pulling the drivers, go ahead and update the caps.

 

[HG5150]

HG5150...Bill's the BEST. You will not be disappointed.

Looking forward to it. Off it goes on Monday.

 

[HG5150]

Replace or recone as a pair.

Any reason why?

 

[HG5150]

Replace or recone as a pair.

Any reason why both?

 

[stuwee]

Any reason why both?

Age, these are older speakers that may have been played hard or hard dynamic peaks at some time. I had to replace a woofer on a Sequel from 1988 and it separated from the surround, after replacing it I got over excited with the music level and the other one separated from the surround. replace both !!

To the OP, why save a few bucks with such wonderful speakers, go with ML replacement woofers, you might have an issue and the great techs can talk you through it. Have you done anything like this before? Can you solder? Just asking...

 

[Spike]

Stuwee,

To the OP, why save a few bucks with such wonderful speakers, go with ML replacement woofers

There's a difference between saving a few bucks and overpaying unnecessarily. With regards to the woofer, I was in contact with Eminence inquiring about this (discontinued) OEM woofer and they said that there's a current model with similar T/S parameters, but 3db less efficient. Given that my speakers are bi-amped, the Classe' is more than capable to make up for the 3db difference. Armed with the information from Eminence, I am exploring and evaluating all possibilities:

1. Replacing 1 woofer from ML - $350 + $25 shipping.
2. Replacing with 2 (current model) woofers from Eminence - $350 + $5 shipping (from Parts Express).
3. Recone 2 current woofers - $170 + shipping.

The best option is to get the woofers reconed, but I would like to reduce transit distance thereby, reducing the chance they may get damaged.

 

[Tosh]

Any reason why both?

For the reason stuwee stated and also because the stereo effect depends on L and R being exactly the same.