IMF owners thread!

Yuppers, I just ordered the caps from the links I posted earlier...good to know they are available. The Pro 3's sound great as they are but can't wait for the improvement.
I guess the "Improved" monicker on these babies went into the crossovers as there are 2 styles to order, version 1 and version 2 with the 4 gang green caps. Sure love the breathy summer breeze bass on these and they are powered by a Sansui AU/TU-919...SANS SWEET!


SansuiSurfer
 
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Yuppers, I just ordered the caps from the links I posted earlier...good to know they are available. The Pro 3's sound great as they are but can't wait for the improvement.
I guess the "Improved" monicker on these babies went into the crossovers as there are 2 styles to order, version 1 and version 2 with the 4 gang green caps. Sure love the breathy summer breeze bass on these and they are powered by a Sansui AU/TU-919...SANS SWEET!


SansuiSurfer

So did your caps arrive? I'm curious to hear how the recap went.
 
IMF 128/20 Woofer Rebuild Pictures

Hey all,

Been awfully quiet here, so thought I'd post a couple of pictures of my 128/20 woofers after their rebuild.

For an as-yet still unknown/uncomfirmed reason, my 128/20 woofers in my IMF RSPM IV Improved speakers got blown - both of them. The coils were fried and blistered. I started a thread on this a couple/three weeks ago, but no conclusions about what might have caused this. Found a bad cathode follower tube in my pre and a possible cold solder joint in my amp, but I'm not convinced that one or the other is the root cause.

I thought about possibly sourcing B139 SP1044's (probably would have been a bit cheaper), but decided in the end to have the woofers completely rebuilt.

The original drivers had no cooling whatsoever (no vented magnets, no vented center dome), so Bill at Millersound installed new domes with four vent holes, so the coil will be a bit more temperature tolerant as the heat will have someplace to escape. He also said they will have greater resolving capabilities, due to other minor tweaks, including flex-lead wire of triple the gauge.

Bill thought they could have just blown because there was no cooling mechanism in the first place - he apparently does quite a few of these. No affiliation w/Millersound, but I thought I'd drop the name in case anyone else needed repair at some point. I was real happy with the work they did on my Alon II woofers, and I'm sure these will be great as well.

They'll be installed tomorrow, so the big boys will be back in business.

128_20_top_view_after_rebuild.jpg


128_20_side_view_after_rebuild.jpg
 
Sorry to hear about your troubles with the woofers but glad that you have apparently found a good fix for them. It is great to know there is this option. I will be really interested in your impressions of these.
 
Hey all,

Been awfully quiet here, so thought I'd post a couple of pictures of my 128/20 woofers after their rebuild.

For an as-yet still unknown/uncomfirmed reason, my 128/20 woofers in my IMF RSPM IV Improved speakers got blown - both of them. The coils were fried and blistered. I started a thread on this a couple/three weeks ago, but no conclusions about what might have caused this. Found a bad cathode follower tube in my pre and a possible cold solder joint in my amp, but I'm not convinced that one or the other is the root cause.

I thought about possibly sourcing B139 SP1044's (probably would have been a bit cheaper), but decided in the end to have the woofers completely rebuilt.

The original drivers had no cooling whatsoever (no vented magnets, no vented center dome), so Bill at Millersound installed new domes with four vent holes, so the coil will be a bit more temperature tolerant as the heat will have someplace to escape. He also said they will have greater resolving capabilities, due to other minor tweaks, including flex-lead wire of triple the gauge.

Bill thought they could have just blown because there was no cooling mechanism in the first place - he apparently does quite a few of these. No affiliation w/Millersound, but I thought I'd drop the name in case anyone else needed repair at some point. I was real happy with the work they did on my Alon II woofers, [/IMG]

I live 13.5 miles from Bill , he is right past Manor Care off of route PA 309.

Bill has become world reknown for his driver repairs.

http://www.millersound.net/indexfl.htm
 
I live 13.5 miles from Bill , he is right past Manor Care off of route PA 309.

Bill has become world reknown for his driver repairs.

http://www.millersound.net/indexfl.htm

You're lucky you're so close to a speaker maestro. I spent quite a bit on shipping, but still well worth it of course to have it done right.

Tinkerbelle, I'll report back once I install them. It's been like 3-4 weeks since I last heard them with the old/non-rebuilt drivers, so I'm doubting I can comment on anything comparison wise, but I do expect them to sound great. :thmbsp:
 
You're lucky you're so close to a speaker maestro. I spent quite a bit on shipping, but still well worth it of course to have it done right.

Tinkerbelle, I'll report back once I install them. It's been like 3-4 weeks since I last heard them with the old/non-rebuilt drivers, so I'm doubting I can comment on anything comparison wise, but I do expect them to sound great. :thmbsp:

It's worth doing it right with those big RSPM's. That's quite a speaker.
 
Glad to hear this all worked out for you Eric. I recall reading your thread on the Yahoo group and was disappointed to hear both of them went awry.

Nice to see they are rebuilt and good to go - looks like they will now last you for a long time to come!
 
Thanks Jeffrey.

Got them all wired back in today and the RSPM IV's are pumping out tunes once again.

I can't say they sound any better/different than before (it's been too long), but in any case, the speakers sound great! I had been subbing in some of my other pairs here and there into the main system, and these are really a step above.

I am, for now, setting the Filter to the In setting, whereas before I had it set to Out, so I suppose I may be losing a bit of bass, but I'm a little gunshy after having these guys blow on me.

How about the other RSPM owners - where do you set your Filter?
 
Mine is always on Out. My understanding based on what it says in the Owner's Manual is that you use the In setting as more or less a subsonic filter. I am always using digital sources so I never worry about any subsonic sound coming through.
 
Got lucky at Goodwill, story in $ & ¢ but here are the pics as I know you guys want pics

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Super Compacts all drivers working, sound great. Lots to compare them to so we'll see. Right now next to the ADS L710s with Paradigm 7SE IIs sitting and ready.

But I got a lot of cleaning to do and some evaluation of the drivers.

Info on which Super Compact these are is welcome as well as any other info.
 
Congrats, another IMF buddy!

Canucker says they have a lot of the sound of their bigger siblings, so I'm sure they sound great.

My IMF journey started with a cheap CL buy of TLS 50's, but the disease spread from there and I spent much more on RSPM IV's.

Let us know what you think after more listening and comparisons!
 
Got lucky at Goodwill, story in $ & ¢ but here are the pics as I know you guys want pics

Super Compacts all drivers working, sound great. Lots to compare them to so we'll see. Right now next to the ADS L710s with Paradigm 7SE IIs sitting and ready.

But I got a lot of cleaning to do and some evaluation of the drivers.

Info on which Super Compact these are is welcome as well as any other info.

Nice! :thmbsp:

Those are the earliest Super Compact which use the Peerless drivers and the Kef B200 SP1014. Nothing wrong with those at all - I've heard their earliest Professional Monitor (pretty well the first speaker they ever made) and they sounded excellent.

One thing you'll want to do before you make up your mind on their sound is replace the capacitors. It's a pretty simple process with the Super Compact and since those are pretty old, there should be quite a significant improvement. http://www.falconacoustics.co.uk (no affiliation) will have a kit for it, however what I would do is e-mail them and show them a picture of what you have and ask for which kit to use.

Congrats on getting a sweet pair of speakers. I think you'll soon discover why we like them so much. :) Like Captouch said they have a lot of the sound of the bigger models. I was told that in demonstrations back in their heyday they would switch from their large Pro Monitor to the Super Compact in the middle and most couldn't tell the difference. They have a surprising amount of bass too, you're in for a treat.

Let me know if you have any questions.
 
Well they are clean, the speaker connections are not reinstalled so that a dual banana plug will work with them and other minor repairs have been done. I still have the cabinets to do but they have been auditioned vs. teh L710 and 7SE IIs and are holding their own.

In my research it too me some time to verify I had all original drivers. The process was finding pictures of IMF speakers and seeing one of them with these Peerless drivers and a post saying these were not original. Further investigation found a post by a former employee of IMF that indicated the angles wires Peerless drivers were used on the IMF speakers. I like having original drivers in the speakers.

As for recapping, I saw the crossover in one speaker and got a list of the caps. I did not see the crossover in the other speaker so I'll pull the woofer again and check it out. Won't be hard to source these caps without paying Royal Post rates for delivery.
But I will look in got what Falcon has available.
 
has any one replaced the foam in their speakers? my TLS 80's had a real vintage funk to them and I mean smell not Jimmy Smith on a B3 Organ.I washed them with Murphy Oil Soap and put a little bowl of coffee grounds just inside.


screenshot app
 
Well they are clean, the speaker connections are not reinstalled so that a dual banana plug will work with them and other minor repairs have been done. I still have the cabinets to do but they have been auditioned vs. teh L710 and 7SE IIs and are holding their own.

In my research it too me some time to verify I had all original drivers. The process was finding pictures of IMF speakers and seeing one of them with these Peerless drivers and a post saying these were not original. Further investigation found a post by a former employee of IMF that indicated the angles wires Peerless drivers were used on the IMF speakers. I like having original drivers in the speakers.

As for recapping, I saw the crossover in one speaker and got a list of the caps. I did not see the crossover in the other speaker so I'll pull the woofer again and check it out. Won't be hard to source these caps without paying Royal Post rates for delivery.
But I will look in got what Falcon has available.

The reason I recommend falcon is one - Jerry is basically the expert on IMF, and two, Alcaps (which they supply) are made by the exact same person that made the Elcaps which you will likely find on the crossovers. I find different capacitors to have different voicings, and getting something made by the original manufacturer is as close as you will get.

Also, the prices are very reasonable and I have priced it out from PartsExpress, Solen, PartsConnexion etc. and find the price to be relatively the same (including shipping) amongst them all.

Of course, do your own research, but that is what I have found.
 
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has any one replaced the foam in their speakers? my TLS 80's had a real vintage funk to them and I mean smell not Jimmy Smith on a B3 Organ.I washed them with Murphy Oil Soap and put a little bowl of coffee grounds just inside.


screenshot app

No, I don't think anyone has. This is an area of critical importance for the operation of the transmission line, so tread carefully!

Transmission Lines are tricky to design properly. First of all the way they are tapered inside the cabinet, the overall size (width and depth) of the line, and the length (of course) makes a difference in the sound. Then, the other critical area is the dampening (the foam). You have to put in the right amount, and not only that use the right type of foam to get the desired effect. This is mainly why transmission lines are not more prominent - difficult to build, expensive to make, and challenging to design correctly. There is no known model to design them by - it's a lot of trial and error.

So, messing with the foam in my opinion is a daunting task and not one you want to undertake, unless the foam is damaged, rotten, or something where you are put in a position where you have to replace it in order to restore its function. In my experience I have only found one pair of IMF speakers with bad foam, and that was in part due to the crossover capacitors exploding and melting the foam inside as well as I think due to the drivers being removed and water getting inside. Hopefully the foam inside your IMFs is fine, I would pull the bass driver out and take a look inside to double check and I would also shine a flashlight in the bottom ports to see it in there.

By the way - have you replaced the capacitors in your IMFs? I owned a pair of IMF TLS 80 IIs last year and did it to them. It's not too bad of a task and made a huge difference - I've recapped 6 pairs of IMFs now and each one made a great improvement. I have pictures of the work and can provide pointers. Let me know.

Jeffrey

Edit:

I was just looking at the picture of your IMFs and it appears that the left one has had its super tweeter replaced. They don't look the same anyways. Could you take a close up of both of them? I may be able to identify them.
 
IMF link for IMF LP (3rd) "Stay All Night" by Loose Caboose (bluegrass country) Ambisonic recording AMB 5203 UHJ stereo compatible record 1981. New old stock, has large quantities I believe. I'm not selling, so only posting here to help IMF owners, rather than on Barter Town. USA website, Inquire if international. Larry is a good guy. http://home.earthlink.net/~larryclifton/mcss.html or if link fails google Larry Clifton's MultiChannelSound Shop. Hope this helps if looking for that music lp. Frank
 
IMF link for IMF LP (3rd) "Stay All Night" by Loose Caboose (bluegrass country) Ambisonic recording AMB 5203 UHJ stereo compatible record 1981. New old stock, has large quantities I believe. I'm not selling, so only posting here to help IMF owners, rather than on Barter Town. USA website, Inquire if international. Larry is a good guy. http://home.earthlink.net/~larryclifton/mcss.html or if link fails google Larry Clifton's MultiChannelSound Shop. Hope this helps if looking for that music lp. Frank

Ah if only he had the one I am looking for, the Reef Petroleum LP. Hard to find, I've got the other 2 already.
 
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