Synthesis LM-310 Speakers

[skaelin]

I just acquired a set of Synthesis LM-310s in mint condition. Does anybody know the specs for this speaker? There is very little info on the web about them. From what I understand, CJ no longer has any info as well. There was a review in The Absolute Sound in Sept/Oct of 1990 but, of course, they listed no specs in the review. Any info would be appreciated.

I already own a pair of Synthesis LM20s and two pairs of LM210s and have heard the Synthesis References System and LM-260s a few times but I never heard the LM-310s so I am looking forward to getting them.

[roberto]

Hola Skaelin,

My dad was a user of the LM-310s. I can say to you that the sound is very neutral and very easy to drive. The components are made in Denmark by Dynaudio. This is one the biggest speaker manufacture of the world. Their components are used by many speaker´s manufacture.

Conrad Johnson brand is known as a very faithfull company. The do sell quality products as their speakers. Just listen to them, and you will find that there is no need for specs...the quality is evident. Good robust bass, with liquid midrange and crystal highs. If you set them right, the stage is wide with tons of sense of 3D. just take them at least 2 to 3 feet away of their´s back wall, and there you go.

I spent a lot of time with my dad listening to the music and enjoying the fantastic musician(s) playing there for us!

Happy listening!

[whnay1]

The woofer is the same as in the SRS System and is customer made in Chicago. The tweeter is the Dynaudio D28 A/F and the Midrange is the Focal 7"

These have excellent deep bass and a lucid soundstage. Dake Fokos and I measured deep bass to 23hz 3dB down.

I will try to dig out the published specs on them. I would suggest buying the 7" midrange and a spare woofer if you can find them on line.

I still use the Synthesis SRS 4-pc System. I have upgraded them to CJD Teflon caps and cardas wiring. Quite an improvement.

[whnay1]

I have attached the only pdf I have of the Synthesis speakers. I still own my Synthesis SRS's and love them!

I hope this helps....

Bill Nay

[gregborowski]

Hello,

I have the Synthesis SRS Reference system but I have two woofers in need of repair (one has voice coil rub and the other has a disconnected braid). Any suggestions on who would be best to repair these? They are both from one tower and I currently have replacements in place. Much appreciated!

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[AnotherJohnson]

There was a set of these with the defects you describe being offered for sale some time ago.

I thought about them off and on for a while, but never acted.

Can you extract the offending drivers and figure out who made them? Maybe CJ could help identify them.

With guitar combo amps and separate speaker cabinets, it’s sometimes possible to do repairs with careful disassembly, realignment, gluing, sealing, etc. But with a guitar amp, distortion isn’t an obstacle to good sound. Not so with audiophile reproduction speakers.

Nevertheless I did this once with Thiels, but I was guided by the original Thiel chief technician.

If you can figure out what they are, you’ve got a better chance of finding a replacement or repair source.

It would be easier to send off the drivers than whole speakers, but it’s not always easy getting them out. Should be a good project.

Cool system though. Very nice vintage look.

[admin]

I've got nothing to add to what AJ said.

Damn, that is one great looking system.

[gregborowski]

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Thank you for the reply and the kind notes. I was able to remove the woofers, although someone had really "glued" them in. As you can see the terminals and braids need to be repaired. Essentially both woofers need to be rebuilt.

The only markings on the woofers are as shown SP101

I should have taken a photo of the internal wiring on these. It consisted of 10-12 twisted wires per terminal. It was the effectively the size of an electrical service supply line. Massive!

I currently have a pair of universal 10" woofers with matching ratings as a placeholder.

I purchased these from The Music Room and knew there was an issue, but at the price - I figured I have some room for repairs and still get a great value.

[admin]

Although it looks messy, these may be repairable. The glue and the connectors can be replaced. If the actual woofer cone is in good shape it could be ok. Google is not helping me with the "SP101" speaker search. Of course the alternative is to just buy a completely new woofer but that will change the sound of the speakers dramatically.

[AnotherJohnson]

The Music Room is where I saw them. I think they listed them on eBay too.

Somebody at CJ ought to know something … but whether or not they’ll tell is another matter. It is possible these were outsourced and rebadged and that the knowledge is actually outside CJ.

I’ll ask a friend of mine who is a driver aficionado to see if he can sniff them out.

[gregborowski]

Thanks!
I did find an SP10 woofer when searching (in case that's really the model number) but it doesn't seem to be a name brand and CJ usually used well known components in their speakers (dynaudio, focal, etc.)

I was able to get a hold of Van L Speakerworks and I am going to ship to them. They seem to think they are repairable.

I really wish CJ published more information on their speakers, but I enjoy the hunt too.

[AnotherJohnson]

These couldn’t have gone to a more worthy owner!

[whnay1]

Here is the web site of the company that made those woofers. They can re-cone, put new voice coils in, and realign existing ones - http://www.vanlspeakerworks.com/

I would try taking each woofer out and rotating them 180 degrees. Sometimes that solves a sagging voice coil that rubs. If not then sent them to this URL.

he also re-cones the Focal 7n501 midrange drivers as well. Try rotating them 180 degrees.

I was involved with Synthesis and still have my SRS's. They are still great speakers.

I hope this information helps you Sir,

Bill Nay

[whnay1]

if you can swing the cost, I suggest Teflon bypass caps in the mid range and tweeter section. In the electronic crossover there are 2 0.10uf Polystyrene caps which are good but replace them with Teflon and you will be amazed.

Also I would add an Audiophile power cord to it vs the lamp cord as supplied.

I did this to my SRS's and modernized them big time.

[AnotherJohnson]

Great information!

[whnay1]

The LM310 and the SRS (Shown) use the same woofer. The LM310 uses one per channel and the SRS Woofer towers use 2 per channel.

These were custom drivers CJ had designed for them. They are solid to 22hz and are very fast. In fact, fast enough to blend with electrostatics.

The people at http://www.vanlspeakerworks.com/ will asses what you need and then call you with a quote. Ballpark $80 each most of the time. Due to the age of these drivers I would send all four in.

Still one of the best speakers I have ever heard.

Bill

[gregborowski]

Bill, thank you very much for the details!

[whnay1]

You are welcome. I have sold the entire Synthesis speaker line. I just love the SRS and I can assist whenever you need it.

[gregborowski]

Thanks Bill. I have two questions for you.
1. Who would you recommend re-cap the crossover with teflon caps?
2. What two amps would you recommend for the mains / subs?
As you can see I have a Premier 350 on the mains but just a MF2250 on the subs.

[whnay1]

Music Technology (Bill Thallman can re-cap with teflon)

I had a Prem 350 and an ACT2S2 and using a solid state for bass. Still one of the best combos I have heard.

For bass I would look for a Mitsubishi DA-A15DC and have the speaker posts put on it. I is about $400 used and is very fast. Battleship construction...