Recommend a woofer for Infinity Epsilon

[Hyendfriend]

My Pass Labs amp recently went DC and fried my wonderful servo drive Epsilon woofers..

I have been looking at options for a replacement..

There seems to be a lot of nice 4 ohm car audio subs..

What about a real home woofer that is musical and goes low??

 

[j_garcia]

What size? I'd give Brian at Rythmik a call. www.rythmikaudio.com or maybe the repair shop at www.partsexpress.com can fix those ones for you? The issue being, you need a driver that will accommodate the cabinet alignment/size that you've got now or it won't sound right.

 

[TLS Guy]

Are you talking about the old Infinity Epsilon speakers with the 12" servo woofer? Trying to replace a driver unless it is an exact replacement is futile.

You have two options and only 2. One is totally new speakers, the other is to have your fried woofers reconed, or recone them yourself with a factory reconing kit.

I doubt a recone kit is available for those speakers, so unfortunately it is probably the end of the road for them. I would part the other drivers out on eBay to recover some cost, if a recone kit is not available.

Unfortunately Orange County Speaker has now closed. They probably had the largest stock of old recone kits and were very experienced at rebuilding speakers. Their head technician has started his own repair business. What parts he has access to I have no idea.

The other speaker rebuilding outfit to recommend for contact is Simply Speakers.

 

[slipperybidness]

And, get yourself some speaker protection!

 

[TLS Guy]

And, get yourself some speaker protection!

Well quite honestly getting those speakers up and running would be a huge undertaking, and in my view not worth the expense and trouble.

Here is the Stereophile review from 2009.

In essence we have a speaker that should have been fully active with its own amps.

Instead we have a speaker that needs a preamp and two power amps, which should be identical.

There is an active crossover/equalizer between the preamp and the two power amps. This unit also connects to the accelerometer on the 12" woofer. The woofer has a long voice coil and large xmax. The woofer enclosure is small and the servo system provides massive Eq. So the bass unit is a power hog. You can see from the impedance curve that the woofer enclosure is NOT braced, or not properly anyway, as it rings like a barrel.

Now the mid and HF units are planar types, with the rear radiation adsorbed.

Now the crossover between woofer and mid is nominally 150 Hz, however you can see considerable overlap between the woofer and mid. I suspect this is because the woofer is at least providing the baffle step loss compensation, and may be more than that.

Now for reasons not explained this equalizer and speaker system are highly sensitive to phase differences in the LF and HF amps, such that not getting this right can result in amp and speaker destruction. It would seem to me that badly mastered source material with an inadvertent phase inversion in the 150 to 300 Hz range could also bring about the same catastrophe.

It is note worthy that both woofers fried, and so both left and right power amps failed at the same time. It is almost certain in my view the speaker system blew up the amp and not the other way around. So that equalizer is probably no good now and would need very careful checking out.

I did note that this system reacted very badly to the variable bias circuits of Krell amps.

So to get these speakers up and running the current woofers and crossover equalizer would have to be ditched. A long throw 12" woofer able to take lots of power and with a large xmax would be required. It would require the correct T/S parameters to go down to 30 Hz in that enclosure with Eq The woofer cabinet needs bracing.

A new active crossover equalizer would have to be designed and put together. It certainly is possible that this could be done with mini DSP and REW.

However, I strongly suspect that this is well beyond the capabilities of the OP. So he would have to ship these 150 lb speakers to someone willing to take on the task. This would be very expensive. There is no guarantee the OP would like the speakers when he got them back!

I think the best advice to give the OP is to start speaker shopping.

 

[TLS Guy]

I have been on the Harmon site and I see your speakers are on the list of supported products. Unfortunately I can not find those woofers in the parts list.

If you really want to salvage those speakers, I would contact Harmon Kardon customer support and see if woofers or recone kits are available.

I think HK is your only realistic option. If they can not get them up and running then part them out.

If you can get the parts and the crossover/equalizer checked out then when you get them repaired make sure all amps are the same and you have speaker protection!

I have looked on eBay, and they have lots of parts but not woofers, which says a lot. There is a pair of woofers without the accelerometer so that is no good to you.

 

[William S. Cortiaus]

Well, I'm coming in late on this post but if you're still considering your options there's some things you may want to consider. Finding a comparable replacement for the Epsilons without spending a LOT of money will likely be a daunting task. As others have said, you can either replace'm or fix'em.

If your wanting to replace them, you will likely get more money for parting them out and selling on eBay. The High Energy drivers are valuable and in demand; the L-EMIM alone can go for $500->$1000 USD. I imagine all the drivers and the SCU alone could get you about $3000-$4000. The rest of the parts perhaps over another $1000. Minus eBay's fees, you'd still likely walk away with >$4k and have a couple of beautiful cabinets to use as firewood. There are other forums as well that could be used in the capacity for sales but you will likely need to sit on things a bit longer.

Alternatively...
You could repair or replace the woofers. You are unlikely to find replacement control woofers but you can still find the same woofer (used in the Sigmas but with no accelerometer/associated PCB). The actual servo accelerometers you have on the woofers of your Epsilons are likely still functional and with a little skill and patience could be transferred to the replacement by either you or a professional (there are still a few out there who repair vintage Infinity models). Replacement woofers for the Sigmas are found relatively frequently on eBay for about $350 each (there's 2 listed as of 7/29/17).
Another option would be to replace the entire servo woofer system with a suitable replacement. I have considered this myself as an option should I face the same dilemma. The Velodyne DD-12 servo subs should serve as nice although not inexpensive substitutes. They are actually superior in my opinion as they have a higher loop gain than the 27 dB of the Epsilons and the added advantage of a very good in-room bass EQ system as well as built in 1250 watt amplification which can be mounted in the Epsilons with some cabinet modifications. The higher servo gain and ability to operate well in a sealed low volume enclosure make them ideal. They also come with a highly adjustable subsonic/high-pass filter and low pass as well to mimic the 30 Hz high-pass/150 Hz low-pass provided by the Epsilon SCU. Slopes are variable from 6-48 dB/octave and phase can be variably adjusted to match original tilt of the crossover region. Cost per DD-12 is about $1200-$5000 depending on version and if new or used; remember, this includes amplification!

If I'm in your shoes, I'm not even thinking of dumping the Epsilons. Even if I'm spending $2500->$5000 to replace the servo system, I'm unlikely to find a speaker system such as these that will fit my system and appeal to my taste. I purchased one of the last Epsilon systems from Harman, brand spanking new, about 15 years ago and still have found no other speaker in the <$20k range that I prefer; and not for lack of looking. My 2 channel system has undergone a complete metamorphosis more than once over the years with the exception of the Epsilons. Yes, I have modded their passive crossovers (replaced all electrolytic caps with poly's and all iron core inductors with air core as well as all resistors with non-inductive equivalents) and their sound has improved even more. The original caps were tested and with the exception of the electrolytics, were still spot-on in-check. I have only had to re-trim the servo pots once since originally purchased. I am fortunate to have spare drivers for everyone of the originals including the SCU, L-EMIMs and servo woofers and so far have never had to use a single one.

I hope some of this may be of help to you, however, I reserve the right to be wrong. Should you decide to part them out, let me know.