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IMF owners thread!

Curlycat said:
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.
Click to expand...

These are non-polar, so no +/- side. I put mine in with all the writing in the same direction, just because.

Take your time, try not to keep your iron on the joint (whether desoldering or soldering) longer than is necessary to melt the solder. . .all the basic stuff.

I found my new caps had slightly thicker leads than the originals, so I had to use an icepick to gently enlarge the holes to allow the new leads to go through. Otherwise, it was quite straightforward. I was able to access the boards without desoldering any of the speaker leads from the crossover - this saved some time and hassle of dealing with more wires to be removed and reattached.

Double check your other solder points while you're in there. Touch up anything that looks marginal.
 
Marcus85 said:
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.

Marcus
Click to expand...

I love that these old speakers are getting the attention they deserve. After we're "done" with them for whatever reason, I hope that all of our IMFs go on to the next generation that will also enjoy them and restore them as needed.

Since IMF are not well known and require some research or experience to know how good they are, I think there's a good chance the ordinary person would pass them up and they'd find their way into the right hands with time.
 
Marcus85 said:
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:

...

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.

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.

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.


Thanks a lot guys!


Marcus
Click to expand...

Hi Marcus,

It was not uncommon for IMF to "hodge podge" parts together to put a speaker together. This doesn't mean it was put together poorly, just with what was on hand. If Jerry states the crossover is that of the original IMF Studio, no doubt he is likely right.

What you have there is an IMF TLS 50 (not the Mk. II). It's identifiable mainly by the black front baffle. The driver looks exactly like the Elac 4EM/101 (see the first page of this thread for a picture), but the odd bit there is the indented, rubberized surround. This must be an early version of this driver as they switched to regular, foam surround. This could be for cost, or sonics, or both, hard to say.
 
Amplifier question

So might have the chance to do some trading and get a first watt F5 Rawson Clone. From all I've read, at 25 watts this might be an ideal amp for the IMF "the Studios" who require 25-60. What concerns me is the class A connection with tube amps, in which Canuck said they tend to not be the best choice, tube amps that is, for IMF's. I'm currently running a Mcintosh MC502 (which is no slouch at 50wpc), even picked up a matching tuner, but this opportunity has presented itself.

Any thoughts?

Thanks
 
c-atle-79bay said:
So might have the chance to do some trading and get a first watt F5 Rawson Clone. From all I've read, at 25 watts this might be an ideal amp for the IMF "the Studios" who require 25-60. What concerns me is the class A connection with tube amps, in which Canuck said they tend to not be the best choice, tube amps that is, for IMF's. I'm currently running a Mcintosh MC502 (which is no slouch at 50wpc), even picked up a matching tuner, but this opportunity has presented itself.

Any thoughts?

Thanks
Click to expand...

Can you demo the F5 with your IMF's first before committing?

Coincidentally, I asked a similar question about tube amps and IMFs just this morning in the Yahoo IMF thread. Canuck didn't like the combo with a particular tube amp (KT120 SEPP), but liked it (at reasonable volumes) with a lower watt SET amp. So I wouldn't generalize and say that IMFs are not good with all tube amps.

Ideally, you could try it out and see for yourself. What amplification are you using now?
 
captouch said:
Can you demo the F5 with your IMF's first before committing?

Coincidentally, I asked a similar question about tube amps and IMFs just this morning in the Yahoo IMF thread. Canuck didn't like the combo with a particular tube amp (KT120 SEPP), but liked it (at reasonable volumes) with a lower watt SET amp. So I wouldn't generalize and say that IMFs are not good with all tube amps.

Ideally, you could try it out and see for yourself. What amplification are you using now?
Click to expand...

Yes exactly.. it's tough to say without trying it out.

There are going to be a couple of issues I can foresee with running low wattage. I believe the Studio measures somewhere around 83-84dB at 1 watt. This means at 25 watts, you are getting around 98dB~ at 1 metre. If you have a rather large room, you may exhaust the headroom of the amplifier if you like to listen at a higher volume.

The only other drawback I can see to lower powered amplifiers is perhaps a lack of dynamics, but, to be honest with you I think this has a lot more to do with the topology of the amplifier than its total power output. So, just like any amplifier, the only way to know if it's a good combination is to hook it up and give it a listen.

Oh and.. the only other thing I can possibly think of is tube amps can saturate at low frequencies if the OPTs (output transformers) are not big enough. However, this is likely not a problem. The 6.5WPC SET tube amp I ran was -10dB at 20Hz (or so), and yes while it did remove that deep bass the IMFs are known for, it still did sound pretty hefty. But, if you listen to material with deep bass in it, this would be something to be concerned about. The First Watt amps I don't have any knowledge of with regards to this, but my feeling is it should be fine.

Other then that, just remember to give any class A amp a good warm-up before letting it play tunes to sound its best :thmbsp:
 
Should have a chance, it's a trade situation, which gets different. I'm running them with a Mac MA502 now, which pushes them nicely, with a great mid range.
 
captouch said:
These are non-polar, so no +/- side. I put mine in with all the writing in the same direction, just because.

Take your time, try not to keep your iron on the joint (whether desoldering or soldering) longer than is necessary to melt the solder. . .all the basic stuff.

I found my new caps had slightly thicker leads than the originals, so I had to use an icepick to gently enlarge the holes to allow the new leads to go through. Otherwise, it was quite straightforward. I was able to access the boards without desoldering any of the speaker leads from the crossover - this saved some time and hassle of dealing with more wires to be removed and reattached.

Double check your other solder points while you're in there. Touch up anything that looks marginal.
Click to expand...

Thanks Captouch! Your advise was valuable and helped me a lot. Just finished recapping both speakers, both working fine. (Better :banana:) the holes in the boards behind the speaker interconnect lugs was too small for the new caps, but fortunately .... I had a heads up :D. I struggled a bit with the de-soldering. I also left the boards attached, so there was less work. Just access was a bit problematic.
 
My TLS50 Mkll speakers recapping is complete. If anyone is contemplating if they can do it - YES, you can. I did and it was not too difficult. Easy actually. I think it was well worth it. My speakers should be fine for another 30 years or so. :thmbsp:


Original main crossover


main_crossover_orginal.jpg


Recapped main crossover

main_crossover_recapped.jpg



Rear panel original

Old_connector.jpg


Rear panel recapped

Rear_connector_recapped.jpg
 
Got my TLS-50 IIs back from the speaker shop with the replacement mids installed. Had a short but enjoyable listening session this afternoon, mostly jazz and female vocals. Initial impression is that these have a HUGE soundtage with warmth and musicality galore. Haven't clued into the bass response yet, though -- will focus on that next session.
 
poorman said:
Got my TLS-50 IIs back from the speaker shop with the replacement mids installed. Had a short but enjoyable listening session this afternoon, mostly jazz and female vocals. Initial impression is that these have a HUGE soundtage with warmth and musicality galore. Haven't clued into the bass response yet, though -- will focus on that next session.
Click to expand...
Great stuff! You must be very happy? Trust me, the bass will find you :music:
 
poorman said:
......... Haven't clued into the bass response yet, though -- will focus on that next session.
Click to expand...

You will love the bass response. Try a few pipe organ music, like "Clay Christiansen - Organ Of The Mormon Tabernacle
KLAVIER (2000) track 09", "Johann Sebastian Bach - Bach, Johann Sebastian; Great Organ Favorites (E. Power Biggs) tracks 1 & 2", "Myung Whun Chung & Orchestre de la Bastille - Saint-Saens : Sym Phony No.3, Messiaen : The Ascension (License)
(1993) track 02" and other organ works.
They sounded great on TLS50 MkIIs and now sound even better on TLS 80 MKIIs.
Enjoy
 
...indeed I am loving the bass response. In fact, I'm loving everything about the sound of these speakers: soundstage, detail, separation of instruments, overall tonal balance. In my opinion, these are one of those speakers that seems to disappear when the music is playing.

I went through my classic rock catalog last night and really enjoyed listening to the Abbey Road medley, the mellower tracks on Slowhand, Pink Floyd's Us and Them, Dire Straits' Telegraph Road, and several Steely Dan tracks. I am powering these speakers with my Pioneer SX-950, which is rated at 85 wpc. It seems to have plenty of headroom. In fact, I don't have any real concerns about the apparent inefficiency of the IMFs.

I bought these speakers on a whim, as I've actually been looking for a pair of Super Compacts, but now that they're in the house, I can tell that they're going to give my Dahlquists a serious challenge. For the first time, I can envision a scenario where the Dahlquists get knocked off their pedestal.

Some questions for you:

1) My pair came with square black platforms attached to the bottoms. Did all TLS-50 IIs come this way, or was it an option? Anyone remove the platforms and place them on stands instead? If so, any recommendations on stand height and brand?

2) I did not have them recapped, and they sure seem to be working great as is. Should I consider re-capping them nonetheless? Anyone have experience using the recap kit from Falcon Acoustics? Is there anything special about the caps Falcon provides for these speakers?

3) Any recommendations for placement? I have them about 7 feet apart, a couple feet out from the rear wall, and a foot or so from the side walls. Anyone toeing them in?

So glad I grabbed these!

Poorman
 
Poorman, I believe all came with the 'plinth' under the speaker. I'd keep it there.

I and others have built low stands with slight tilt to take advantage of those plinths. Basically, stands modeled after the ones that came with later models of the 50, RSPM IV, etc. I posted specs of the ones I built. Will post a link to it.

If they're keepers for you, I'd recap them. Most of us use the Falcon kit, since the Alcaps they use are most similar to the Elcaps originally in there. It's a pretty easy recap. You can remove the woofer and double check your caps are original (black caps with red wax ends) - there's always a chance that a PO recapped them.

Mine are probably 7-8ft apart and maybe 1 foot from back wall. Haven't played around with placement much, but have sounded good wherever they've been.
 
poorman said:
...indeed I am loving the bass response. In fact, I'm loving everything about the sound of these speakers: soundstage, detail, separation of instruments, overall tonal balance. In my opinion, these are one of those speakers that seems to disappear when the music is playing.

I went through my classic rock catalog last night and really enjoyed listening to the Abbey Road medley, the mellower tracks on Slowhand, Pink Floyd's Us and Them, Dire Straits' Telegraph Road, and several Steely Dan tracks. I am powering these speakers with my Pioneer SX-950, which is rated at 85 wpc. It seems to have plenty of headroom. In fact, I don't have any real concerns about the apparent inefficiency of the IMFs.

I bought these speakers on a whim, as I've actually been looking for a pair of Super Compacts, but now that they're in the house, I can tell that they're going to give my Dahlquists a serious challenge. For the first time, I can envision a scenario where the Dahlquists get knocked off their pedestal.

Some questions for you:

1) My pair came with square black platforms attached to the bottoms. Did all TLS-50 IIs come this way, or was it an option? Anyone remove the platforms and place them on stands instead? If so, any recommendations on stand height and brand?

2) I did not have them recapped, and they sure seem to be working great as is. Should I consider re-capping them nonetheless? Anyone have experience using the recap kit from Falcon Acoustics? Is there anything special about the caps Falcon provides for these speakers?

3) Any recommendations for placement? I have them about 7 feet apart, a couple feet out from the rear wall, and a foot or so from the side walls. Anyone toeing them in?

So glad I grabbed these!

Poorman
Click to expand...

Glad to hear you are enjoying them!

Like captouch has said, recapping them is a good idea. Not only for the sonics to be properly balanced, but also because it's good measure to protect the speakers. Old capacitors don't have the same power handling capabilities after all these years, and while it is somewhat uncommon for a capacitor to blow up, it can happen.

Getting them up on stands is a great idea too - I highly suggest this. Just make sure the stands are sturdy and can handle the weight. The IMF stands have a slight tilt of about 5 degrees, and typically raise the speakers up about 4-5" off the floor. I believe the plans captouch call exactly for this.

As for placement, I myself need to experiment more with this but I find having them fairly wide apart, say, about 9-10 feet and then toed in 30-40 degrees seems to work best. Experimentation is required of course.

One last thing - those Audax tweeters, the domes seem to dry out. From what I've researched the domes have some sort of a pliable material that when dried out, will reduce the SPL of the tweeter. You may find the highs to be a bit reticent, even after the recap. If so, I recommend replacing with the Audax replacements available on http://www.falconacoustics.co.uk. Also, see the first page of this thread for some information on restoring the speakers.

If you need any pointers on anything, feel free to ask. :)
 
canuckaudiog said:
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.
Click to expand...

The Acurus amp is still forthcoming... :tears: So my hunt for a good inexpensive amp is till on,,,

How will Arcam amps pair with the TLS50's? I can get a FMJ A22 second hand for a "fair" price, or a new FMJ A28 for $200 more. I know the A22 can current 20 Amps. Not sure about the A28 currnent delivery amps?

What do you guys think?
 
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"Like captouch has said, recapping them is a good idea. Not only for the sonics to be properly balanced, but also because it's good measure to protect the speakers. Old capacitors don't have the same power handling capabilities after all these years, and while it is somewhat uncommon for a capacitor to blow up, it can happen."

Canucker -- I looked at the recap kits Falcon offers and noted different offerings, including 5% tolerance, 2% tolerance, and polyester "where required". Do you know which kit includes the closest to OEM caps? Thanks!
 
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