IMF owners thread!

I am driving mine with an oder McIntosh integrated rated at 70W per channel - but I understand McIntosh rates rather conservatively - I still have a more powerful Class-d amp - might be worth a try as well. Anyway, I like those speakers a lot - they might just be my final pair for the living room.
 
Hey IMF fans!

It's been a long time since I have been around. I have not touched my stereo for months nor done anything really stereo-related for some time. Recently, I spent some time getting my listening space in order and have been enjoying music, which has been great to say the least.

Additionally, my wife and I were talking and we sorely miss the old IMF RSPM Mk IVs we used to own. A hunt through the classifieds (and posting a wanted ad) has yielded an interesting prospect - a pair of IMF Professional Monitor 3s. I am actually familiar with this particular pair as I have done work on them myself years ago. Though, they're an early version of the PM3 according to my notes, but should still be fairly close to the Mk IV. I am excited to have IMFs in the house again!

Question for you guys - is it possible to replace the B139 6171 with an SP1044? Specifically, I want to replace the B139s with Falcons replacements. Also, has anyone replaced the B110s in their IMFs with the new Falcon B110? Curious to know how much better they are.
 
Hi,,long time you will have to patch up the hole (router) to change the woofer, not an easy task. Hopefully you get improved MK III ,Different X-over better in sound.You get them cheap, they are so heavy and hard to crate better to go get them by yourself.
 
Hi IMF fans.....

Has anyone got a copy of the CM3 xover layout and values? Jerry at Falcon has what I'm after. Cheers
 
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Hi,,long time you will have to patch up the hole (router) to change the woofer, not an easy task. Hopefully you get improved MK III ,Different X-over better in sound.You get them cheap, they are so heavy and hard to crate better to go get them by yourself.

From my notes, they're a PM3 MK1, so I don't think they are the improved version. The plan is to try and source a set of those crossovers, though.

So the hole itself needs to change? Bummer. I guess I'll have to stick with the 6171 until I think of a creative way to get the SP1044 in there.
 
Personally I'd wait to find a set of late model Mk IV's and not mess around with earlier PM's.

As far as the Falcon B139 is concerned it basically just has a better power handling figure which will certainly be an improvement over the previous 50 watters
 
Personally I'd wait to find a set of late model Mk IV's and not mess around with earlier PM's.

As far as the Falcon B139 is concerned it basically just has a better power handling figure which will certainly be an improvement over the previous 50 watters

The chances of finding a set of Mk IVs in my neck of the woods is extremely rare. The one set I had was the only set I've seen in 7 years of hunting - and the person I sold them to wants astronomical amounts.

I've owned them, so I know what they're all about. I'm fine with trying to make these IMF PM3s even better, I think they're worth the effort. The plan is to have these for the long haul.

As for swapping drivers, beyond the wattage improvement, it's really just because these drivers are long in the tooth and are no longer going to be performing like they did nearly 50 years ago. I think I might start with the B110 and then do the B139 at some point down the road.

If anyone has any PM3 Improved crossovers, by the way, let me know!
 
Hi , in page 32 the pictures of the MK III improved x-over, but I'm not ready to departed with my X-over, yes Falcon sure have the one,but at what price,you never know it's good to ask.
 
I guess I know why I will at least try never to part with my IMFs:biggrin: - whereby I could not resist temptation - and got myself a very nice pair of RSPM MKIV :jump:. They are pretty rare in my part of the world as well - and so when another deal didn't materialize (I don't even know if the "seller" actually had a pair for sale - but that is a different story), I drove south for about two and a half hours (each way) and collected those. This seller turned out to be a real collector (he had a beautiful and fully restored Marantz receiver [for example], so the speakers are in a very nice condition indeed. I admit I was slightly surprised by their size (on stands) and by their weight. Carrying them down a flight of rather steep stair was not the greates of funs - but boy, I am so glad I picked those up - as I find them really a step above my TLS80. They play similarly (of course) but everything is bigger and more solid - to my ears a clear upgrade - especially if the filter is set to the "out" position - I find that cleary audible in terms of transparency.
Recapping has already been started. Gone are those white cement resistors - in went the above mentioned metal- and thick-film ones by Futaba and Caddock - a highly recommended upgrade for a lot smoother high frequency presentation. The small value electrolytes were changed to Siemens MKL - and the big caps will be swapped with the ones sent from the trusted people at Falcon. Already these speakers are absolutely stunning in every way and as written above - those will stay (unless some catastrophe forces a sale).
 
The only person that would probably have that circuit would be Jerry.

I did check with him but he did not have it.

Hi , in page 32 the pictures of the MK III improved x-over, but I'm not ready to departed with my X-over, yes Falcon sure have the one,but at what price,you never know it's good to ask.

Thanks Yvan! That's very helpful. I am going to keep an eye out on eBay to see if a pair turns up. You never know. If you decide to part with yours, let me know - would be happy to send you the ones that are in there now in exchange. But I understand wanting to keep this stuff.
 
I guess I know why I will at least try never to part with my IMFs:biggrin: - whereby I could not resist temptation - and got myself a very nice pair of RSPM MKIV :jump:. They are pretty rare in my part of the world as well - and so when another deal didn't materialize (I don't even know if the "seller" actually had a pair for sale - but that is a different story), I drove south for about two and a half hours (each way) and collected those. This seller turned out to be a real collector (he had a beautiful and fully restored Marantz receiver [for example], so the speakers are in a very nice condition indeed. I admit I was slightly surprised by their size (on stands) and by their weight. Carrying them down a flight of rather steep stair was not the greates of funs - but boy, I am so glad I picked those up - as I find them really a step above my TLS80. They play similarly (of course) but everything is bigger and more solid - to my ears a clear upgrade - especially if the filter is set to the "out" position - I find that cleary audible in terms of transparency.
Recapping has already been started. Gone are those white cement resistors - in went the above mentioned metal- and thick-film ones by Futaba and Caddock - a highly recommended upgrade for a lot smoother high frequency presentation. The small value electrolytes were changed to Siemens MKL - and the big caps will be swapped with the ones sent from the trusted people at Falcon. Already these speakers are absolutely stunning in every way and as written above - those will stay (unless some catastrophe forces a sale).

CONGRATS!!

The Mk IV are one of the pinnacles of IMF speakers in my opinion. I have not heard them all, but the Mk IV is right up there I am sure. Very expensive in their day! And such a wonderful sound. You will be mightily impressed with them after the crossover restoration.
 
Canuck,Jeff you will put pictures of these prof. , one of these day, showing the x-over and details of the inside
 
Canuck,Jeff you will put pictures of these prof. , one of these day, showing the x-over and details of the inside

Sure thing, here you go. This is the front of one:
1939682-imf-rspm-mk-i.jpg

And here is the crossover, before being recapped:

20120917_200424.jpg

Back in the day when I contacted Jerry about these speakers (this was when I found the ad for them by the original owner, in 2012), he identified them as an early PM3 Mk1 crossover. I suppose that makes these Professional Monitor 3s, just early ones. They do have the dowels in place for the woven pattern of insulation inside the speaker, which is a feature found on the PM3, so perhaps it makes sense.

Sound-wise they are definitely warmer than I remember (thinking back to my RSPM Mk IVs). The Mk IVs had a similar neutral character, but were more focused and precise. These older PM3s are on the warmer side, with a not as defined stereo image, but they have that great big speaker sound as well as prodigious bass. I actually quite like the way these sound, the Mk IVs were wonderful but these are easier to listen to - relaxing. Still very detailed in the upper registers, and the midrange sounds oh so sweet and uncoloured. Very, very enjoyable.

A question: Yvan do you know where IMF PM3s were built? I'm thinking of the newer style PM3 with the slots raised, the green coloured insulation and also the new style fronts with the metal inserts. Reason I ask is I am trying to determine if my PM3s were built in the same shop as the newer PM3s, or not. It might help me determine how old these are.

Also, for more interesting information, on the back of these it is marked as "Type: MDUW" and serial number is 3105. No idea what MDUW means, but from a previous e-mail of Jerry's MD seems to stand for Monitor Domestic - no idea what the UW could mean. Any ideas?
 
Hi Jeff, the insulation is pink at the bottom,the effect of green come from the green net., these I'not sure if they are consider as PM3 because,PM1,PM2, they are laminate only in the back (black Formica), The pair I have (bought from my friend $1300 in 1976-77.) Was not improved at the time like end of 1972, received the new x-over middle of 1973 with improved plate.They are serial # 1008 l and 1008 r writen on the wood next to X-over,the back connectors both on left side when looking facing front. The dowel pin are they on both side panels(2+2 each separation section) or applied on flat part of TL? The tube for the mids is cardboard 6" diam.? If you look all MK 3, the mid is place on a round recess ,you're the mids fit perfectly in a recess with is same shape.I will say you're have to be made early 70, what year the Laminate start to appears on the market? Wood finish?the B139 are they the model with 3 screws on magnet or older?
 
Hi Jeff, the insulation is pink at the bottom,the effect of green come from the green net., these I'not sure if they are consider as PM3 because,PM1,PM2, they are laminate only in the back (black Formica), The pair I have (bought from my friend $1300 in 1976-77.) Was not improved at the time like end of 1972, received the new x-over middle of 1973 with improved plate.They are serial # 1008 l and 1008 r writen on the wood next to X-over,the back connectors both on left side when looking facing front. The dowel pin are they on both side panels(2+2 each separation section) or applied on flat part of TL? The tube for the mids is cardboard 6" diam.? If you look all MK 3, the mid is place on a round recess ,you're the mids fit perfectly in a recess with is same shape.I will say you're have to be made early 70, what year the Laminate start to appears on the market? Wood finish?the B139 are they the model with 3 screws on magnet or older?

I'm only going by what Jerry Bloomfield has told me, and he said the crossovers are properly identified as a PM3 Mk1, so I have to imagine the rest of the speaker is too.

Regarding the rest of your questions, I would have to pull the bass driver off and take a look inside. I might do that this weekend.

Early 70s sounds about right as far as when they were constructed.
 
Hi, when you google Imf prof Mk 3,it bring you to old audiokarma thread 2013,if you look at the site IMF, professional mk3, they say Mk3 have to be the 4th generation, you're x-over can not be so different,even in mk 1 or 2. You're have 3 air coils with one core coil,the x-over it is glue on the usual foam,I'm pretty shure the pattern road of circuit never really change,okey some difference but not drastically different, value change of components. The dimension? Can be the answer. The serial on x-over # 430,do the other speaker have the match?
 
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