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IMF owners thread!

mech986 said:
Congrats and Welcome! If the cost isn't a problem, the selected 2% caps would be great. So what's the story behind the acquisition, how did you find them and all that? Do you know which B200 are installed?

Also, pics are always welcome. You might not know but:

:worthless
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Thanks! I absolutely looove these speakers :thmbsp:

Well I was looking for a pair of stereo speakers that has some good bass oompf. I am faily new to Hi-Fi, but are not crazy about 2.1 or the 5.1/7.1 set ups. I am old school and like stereo. There is something about big speakers with large drivers that stirs my feelings :banana:

After about one month or so of searching and not really finding anything I really liked or could afford, I saw this pair of IMF's for sale. I quickly did my homework and knew these were keepers. I bought them from a dealer who got them from the first time owner. Cabs are well looked after, so the cloth and badges.

The super tweeters are original, tweeters and mids have been replaced. I have the original mids. Still in good condition. Not sure with what they have been replaced, but I believe better units though. The dealer has a very good reputation.

I am not sure which model B200 but I will definitely look when I tackle the recap.

IMF_2.jpg


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I am looking for suggestions on a decent inexpensive second hand amplifier to drive these. What do you guys think an Acurus amplifier will do with these boys?
 
Curlycat said:
I am looking for suggestions on a decent inexpensive second hand amplifier to drive these. What do you guys think an Acurus amplifier will do with these boys?
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First off wow those are freakin' nice! I am usually not one to say replace drivers (since to do that properly, the crossover would require modification) but man, they did a stellar job on that! Those metal stands are a real nice touch too. Whoever worked on those really loves IMF speakers! Out of curiousity, on the back, does it say TLS 50 IIa, or just TLS 50 II?

You may find once you get into the crossovers that they already have had work done to them. I can't imagine they would be all original with replaced drivers and all that work done to them. If they have had some mods done, post some pictures of that too. What a great find you have there, I'm glad they sound great! Keep the original mids and I wouldn't worry too much about swapping the originals back in unless you get an inkling to do so.

The Acurus will likely do fine. I find modern integrated/power amplifiers are more suitable because of the fact they have better transient response in comparison to old amplifiers. The IMFs enjoy current (not necessarily high power though) as well as a "speedy" and neutral sounding amplifier. The Acurus, I believe, will fit this bill just fine. The most critical part for IMF speakers in terms of amplification is really the bass because the B200 has a loose suspension and can sound somewhat woolly and undefined when driven with something that is not really "quick", if you catch my drift.

Thanks for sharing the photos and, keep on enjoying the tunes!

Edit: By the way - IMF speakers are usually best enjoyed with the midrange on the inside, not the outside. Of course that may vary with your listening room and preferences, but that is what IMF recommends and how most people use them.
 
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canuckaudiog said:
Those metal stands are a real nice touch too

Who made those stands. I have TLS80MkIIs and the stands have rollers on them so I do not use them. I feel the rollers will affect the bass reproduction. Am I correct in thinking?


Edit: By the way - IMF speakers are usually best enjoyed with the midrange on the inside, not the outside. Of course that may vary with your listening room and preferences, but that is what IMF recommends and how most people use them.
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The IMFs have Serial Nos. L & R. If the speakers are positioned L & R correctly, the midranges are correctly inside.
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canuckaudiog said:
First off wow those are freakin' nice! I am usually not one to say replace drivers (since to do that properly, the crossover would require modification) but man, they did a stellar job on that! Those metal stands are a real nice touch too. Whoever worked on those really loves IMF speakers! Out of curiousity, on the back, does it say TLS 50 IIa, or just TLS 50 II?


The Acurus will likely do fine. I find modern integrated/power amplifiers are more suitable because of the fact they have better transient response in comparison to old amplifiers. The IMFs enjoy current (not necessarily high power though) as well as a "speedy" and neutral sounding amplifier. The Acurus, I believe, will fit this bill just fine. The most critical part for IMF speakers in terms of amplification is really the bass because the B200 has a loose suspension and can sound somewhat woolly and undefined when driven with something that is not really "quick", if you catch my drift.

Thanks for sharing the photos and, keep on enjoying the tunes!

Edit: By the way - IMF speakers are usually best enjoyed with the midrange on the inside, not the outside. Of course that may vary with your listening room and preferences, but that is what IMF recommends and how most people use them.
Click to expand...

Thanks man! I do think they are real nice too :thmbsp: I can see the first owner loved these speakers. He had the tweeter mods done. The dealer whom I bought it from loves audio and he comes highly recommended here. He changed the mids for me.

I have ordered capping the kit from Falcon. I will post pics as soon as I get the parts. Not sure how long it will take to arrive here from the UK.

I checked the back - is just TLS50 Mkll - not the Mkll A version... tell me more about the Mkll A version please?

I am glad to hear that the Acurus amp will work well. I am not sure which model the dealer is going to get for me... is in the pipeline. Cant wait. :D I will update as soon as I know more. My current amp is the Yamaha A-S300. It is OK, but sometimes I think it lacks drive....?

I LOVE MY TLS50's :thmbsp::thmbsp::thmbsp:
 
Curlycat said:
Thanks man! I do think they are real nice too :thmbsp: I can see the first owner loved these speakers. He had the tweeter mods done. The dealer whom I bought it from loves audio and he comes highly recommended here. He changed the mids for me.

I have ordered capping the kit from Falcon. I will post pics as soon as I get the parts. Not sure how long it will take to arrive here from the UK.

I checked the back - is just TLS50 Mkll - not the Mkll A version... tell me more about the Mkll A version please?

I am glad to hear that the Acurus amp will work well. I am not sure which model the dealer is going to get for me... is in the pipeline. Cant wait. :D I will update as soon as I know more. My current amp is the Yamaha A-S300. It is OK, but sometimes I think it lacks drive....?

I LOVE MY TLS50's :thmbsp::thmbsp::thmbsp:
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Ah okay I figured it was the TLS 50 II and not the IIa. The reason I ask is because of the stands - the difference between the TLS 50 II and the IIa is that, the IIa had a different set of drivers, all designed and manufactured by ELAC for IMF, and also it came with stands. I had wondered if perhaps these were IIas and changed to Kef/Coles drivers or maybe the stands were made for them, or perhaps they were found from a set of IIas. Either way, those stands are a welcome benefit to IMFs and improve the bass response. Lifting them off the floor and supporting them properly, IMO, is a must.

When the caps come in, let me know if you would like any pointers on doing the recap. What I can tell you off the top of my head is the crossover is best accessed by taking the Kef B200 woofer off, and also, there are capacitors located on the speaker terminal where the attenuator is situated. Of course, because these have been modified, do check over the crossover and make sure you replace only the capacitors that are still original (these will be black with red ends ELCAP branded capacitors).

As far as an owners manual I haven't seen one for the TLS 50 II, but I will dig around and see if I have one on my hard drive stored somewhere. The manual is basically the same for each model, the only difference of course is with the higher models like the Reference Standard Professional Monitor, it has more attenuation capabilities and the manual goes more indepth on those. Otherwise, the rest all applies.

The A-S300 is definitely lackluster for those speakers. Not as an amplifier, but just in terms of matching. Your IMFs are a revealing speaker and will be sensitive to the upstream gear you connect to it - meaning, the better quality amplifier, source, pre-amplifier and cabling you use, the better those IMFs will sound. These are worth investing into some good quality gear to run them with, which I am sure you can already tell.

Keep us posted on how everything turns out! It sounds like the dealer is a fantastic business to deal with. :) If you have any specific questions, don't hesitate to ask.
 
wtaylorbasil said:
Who made those stands. I have TLS80MkIIs and the stands have rollers on them so I do not use them. I feel the rollers will affect the bass reproduction. Am I correct in thinking?
Click to expand...

I still think the speakers will sound better on the stands, but one thing is for sure is that the bass is not decoupling through the stands. You could remove the rollers or fit spikes to them, but then of course you lose the ability to move them around with ease. Either way, allowing the bass to travel underneath the speaker will certainly take out a bass hump they are experiencing now. It should clean it up and make it sound more detailed, not to mention the midrange and tweeters are producing a more flat response when the speakers are on their stands.
 
Curlycat said:
That is an awesome offer from you, Thank You Very Much! I will post pics as I pull the crossovers and the attenuator. Keen to see what has been replaced already, if any...

I am sure I will have quite a few questions still, I am just very lucky to have found you and the dealer... and my TLS50's :D
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Awe shucks. :D You're most welcome. Let us know what you end up finding. :yes:
 
Curlycat said:
I am looking for suggestions on a decent inexpensive second hand amplifier to drive these. What do you guys think an Acurus amplifier will do with these boys?
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I read that Rotel also delivers good current. Anyone how Rotel will pair with the TLS50's? In particular this Rotel RA-980. 100WPC at 8Ohm.


Here is another pic- busy cleaning the cabs ...

TLS_Avatar.jpg
 
Hi there,

I am new to this forum, so I'll give you a quick intro: I am Marcus, 28 years old and I am originally from Mönchengladbach, Germany, which is near Düsseldorf and Cologne in the West, also called the "Rhineland" area. I have spent some years in the UK studying and I have also learned to really like British Hi-Fi equipment. I have owned a Mission Cyrus II and an EAR 834P valve preamp for some years now.

Recently I've got my hands on a pair of IMF speakers which I have decided to restore as these kind of speakers are quiet rare in my neck of the woods. The speakers do not have a label on them, but they seem to be TLS 50s, the chassis featured are KEF woofers and properly IMF mids with rubber surrounds and peerless tweeters (which look surprisingly similar to Germany "Heco" ones) together with super tweeters. All chassis are in good condition, but one of super tweeters is not fully working!

As one of my super tweeters isn't working properly, I would like to replace the pair. According to the information that I could find on the internet, the IMF TLS50 use the Coles 4001G super tweeters which are also available from falcon acoustics in 16 Ohms. I have seen some photos of the 4001 on the internet and every Coles 4001 I have seen has quiet a big rear cover which measures about 60mm in diameter. However, my tweeters only have plastic rear covers of about 25mm in diameter and when I use my multimeter it meters around 44 Ohms which would roughly be 55 Ohms impedance. Both super tweeters have the same impedance, so I guess 55 Ohms is correct, even though it sounds unusual.

I have attached some photos of the tweeters so you can get a better impression of the super tweeters that I am talking about.

Would anyone be able to identify the super tweeters for me as I would really like to get the right ones to replace them.

I will also post some more photos of all the components tomorrow.

Thank you very much folks!

Best regards


Marcus

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Welcome Marcus.

Just curious, did you swap the super tweeters to make sure it wasn't a crossover issue? If both measure the same, you may want to double confirm it's actually the super tweeter and not another issue before replacing it.

Also, you may want to post a picture of the speakers themselves to have the group confirm they are TLS 50's.
 
Hey Marcus

Welcome to the IMF league :) I really enjoy my TLS50's. I don't think I will ever get rid of them. Nurture and restore your's, they will serve you faithfully with awesome & pleasing sound :)

Post some pics!

Good luck!
 
That is the original Coles supertweeter, essentially derived from a reverse driven microphone diaphragm, that is why it originally had such a high impedance and looks like it might fit on the end of a microphone body.

Best to determine if you can find a working original, or just open up the mounting for the newer and current versions which use ferrite magnets, hence the larger diameter.
 
canuckaudiog said:
When the caps come in, let me know if you would like any pointers on doing the recap. What I can tell you off the top of my head is the crossover is best accessed by taking the Kef B200 woofer off, and also, there are capacitors located on the speaker terminal where the attenuator is situated. Of course, because these have been modified, do check over the crossover and make sure you replace only the capacitors that are still original (these will be black with red ends ELCAP branded capacitors).
Click to expand...

Yippee, got my caps today - now one question. I will obviously replace like for like (and as you have suggested, replace only the originals, leaving in any modified caps that goes with the replaced drivers) BUT, does these caps go any direction, or do they have a + and - side?

Any other pointers would be appreciated. I have never done this before, but have soldered in the past.

Caps1.jpg
 
Here is the access pictures of the crossover.

B200_driver_out.jpg


Crossover_nest.jpg





Seems like all the caps are still original? Not sure about the purple one, that original? (and the square white block on the left?)

crossover_detail.jpg





and here is of the actual B200 driver Model SP1039

B200_driver_detail.jpg
 
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Hey,

thank you everyone for giving me a warm welcome to Audiokarma, I really appreciate it!

@captouch: I have tested the supertweeters independently on a beat frequency oscillator (luckily my dad owns one) and one of them gives out a cracking noise in the really high areas which the other one doesn't produce, that's why I figured that one of the supertweeters isn't working properly.

@curlycat: Thanks for the warm welcome, I'll do my best to restore those old beauties!

@mech986: Thanks for the info on the Coles tweeters - it makes sense that my ones are an older type. The thing that bugs me is that my tweeters are metering roughly at 55 Ohms impendance so replacing them with new 16 Ohms ones would lead to a change of the capacitors on the crossover, right? Maybe I need to take some time and actually find a pair of "old" Coles supertweeters.

My plan is to renew the capacitors on the crossovers anyway.

As promised, here are some more photos, I hope that they shed some more light on what type/kind of IMF TLS I actually own.

Here are the cabinets:

mk7v8tuc.jpg


wlleabbr.jpg


The woofer, a KEF SP 1014:

h65z332i.jpg


The midrange, I guess it is an "IMF own brand"? But I am not sure, it has rubber surrounds which seem to slowly come off from the chassis - I guess they can be glued back in place though.

eqo9925j.jpg


768thuw6.jpg


The tweeter, a Peerless, which looks very similar to the tweeters made by Heco in the 70s and which were used in many German made loudspeaker cabinets.

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Finally, the crossover - I have been in contact with Falcon Acoustics and they told me that the capacitor layout is actually that of IMF studios.

qji7l2n9.jpg


Thanks a lot guys!


Marcus
 
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