IMF owners thread!

Hi Chris, these Tls have no tube behind the mids?all the coils are in the same direction,yes they really are very early version.

Yes, there are tubes behind the mids. They appear to go all the way to the back of the cabinets.

Caps are ordered. Now I just need to get my GF's car out of my garage so I can start tearing down the cabs. The car is a '98 BMW M-Roadster, so I'm not in that much of a hurry. What a fun car to drive! 280 hp roller skate.

One thing I need to figure out is the stuffing. These had poly pillow stuffing inserted at some point, though I can see the evidence of both fiberglass and sheeps wool. I always heard these had long hair sheep's wool for stuffing in the line. Now Jerry at Falcon tells me the very early ones had fiberglass mats stapled to the sides of the lines and very little stuffing. Just figures, I've already sourced a full fleece from some country friends and spent days washing and drying the wool in preparation.
 
On a "Super Compact" topic,

Some time ago I bought a pair of Super Compact Mk II's from a chap in Parkville, Victoria and were a set that were a bit of a " Basket Case". Blown drivers, cracked in half Crossover board just to mention a few issues.

He bought them in this condition himself and tried to repair them on a low budget and found that it wasn't going to happen so he decided to quickly move them on, thus I bought them in the same condition.

I've had them for a couple of years now and have been hedging my bets on gaining the correct drivers required and various parts that I needed to get them back into being a serviceable pair of speakers.

Well I've finally gotten all the drivers / parts together and now need to refinish the boxes on the outside and put them back together. They should be a cracker set again and I'm sure they'll live on to make beautiful music for a long time coming.

8/22 Elac Bass drivers are getting rather hard to come by nowadays at an affordable price to make it cost effective. There are plenty available at high prices in Europe, but those continue to just sit there and will never sell I feel. Everything needs to be priced accordingly and there's no point in putting super high prices on parts when the finished completed item only sells for a few extra dollars. Why would you bother when you can just go and buy a fully working set at an affordable price point ?

Cheers.
 
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Hi everyone, I'm new on Audiokarma but I'm part of the IMF and TDL group on Discord (https://discord.gg/a9Uh7P).

What do you think about replacing the capacitors?
I have the IMF RSPM Mk.IV Improved (serial P6401). I've listened only my IMF so I have no idea how much they could be improved with this operation. I have found a technician that could do the replacement, is there any alternative to the Falcon Acoustics kit? Why do they call the speakers MK 1V?
 
Hi Ziopanna,

Welcome to the IMF page on Audiokarma.

I wouldn't mention the Discord site too loudly or it's owner around here as many won't be a part of that "childish" type of social media and I'm one of those that's strongly against it. Sadly the type of people it has attracted is not what most sensible level headed people want to be associated with. I was originally one of it's first members, but rather quickly voluntarily revoked my membership due to the nature of many on that site and some of the ID's that were used were hideous to say the least and that pretty much described the sort of mentality we were dealing with. Sorry not for me. Discord was basically set up for gamers and I'm not a gamer.

Now as far as your question is concerned as you can see from my avatar I have exactly the same set as yourself. I just recently did the full capacitor rebuild myself and took many photos along the way but still can't put them up here as this site does not have it's own picture hosting facility, rather one has to use a third party hosting service and that's something I won't do. Photobucket proved that to me a few years ago how they held everyone to ransom when they started charging for the privilege, thus most Websites and Forums lost all their images which makes many threads useless without those images to describe and act as a tutorial.

Anyway I used Falcon's cap set as they are the best fitting to replace the old Black Elcaps. The space allocated for the many Elcaps is rather restricted so one is best to use them.

As far as the model naming is concerned, the Mk IV is a evolution of the "Original", "Professional Monitor" that had a version 2 and 3 and then morphed into the "Reference Standard Professional Monitor" (RSPM) that is the
Mk IV.

I guess amongst us IMF users the term "Mk IV" was the abreviated name used to identify this model opposed the full model identification name.

Effectively there were two major changes during the Mk IV's lifespan which were the driver line up changes and thus they were the MK V and VI but they were never called those names officially, then the next change became the RSPM Mk VII that had a completely different driver layout with the midrange being up above the tweeters.

Which driver combination do you have ? the Elac / Celestion combination (Mk V) or full Elac line up (Mk VI) as both these variants were officially named MK IV "Improved".

Also while I remember you have the "Genuine Factory Improveds" as this is clearly denoted with the "P" in the serial number. Owners that that had the "Former" Mk IV's could buy a Kit containing the upgraded drivers and received the "Improved" sticker to place on the front panel, but the serial number didn't change. This is the way to identify the Factory released speakers from the owner upgraded units.

Also as you are a new member, may I ask which country you are located in as you don't have it showing in your profile ?


Cheers.
 
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Hi Ziopanna,

Welcome to the IMF page on Audiokarma.

I wouldn't mention the Discord site too loudly or it's owner around here as many won't be a part of that "childish" type of social media and I'm one of those that's strongly against it. Sadly the type of people it has attracted is not what most sensible level headed people want to be associated with. I was originally one of it's first members, but rather quickly voluntarily revoked my membership due to the nature of many on that site and some of the ID's that were used were hideous to say the least and that pretty much described the sort of mentality we were dealing with. Sorry not for me. Discord was basically set up for gamers and I'm not a gamer.

Now as far as your question is concerned as you can see from my avatar I have exactly the same set as yourself. I just recently did the full capacitor rebuild myself and took many photos along the way but still can't put them up here as this site does not have it's own picture hosting facility, rather one has to use a third party hosting service and that's something I won't do. Photobucket proved that to me a few years ago how they held everyone to ransom when they started charging for the privilege, thus most Websites and Forums lost all their images which makes many threads useless without those images to describe and act as a tutorial.

Anyway I used Falcon's cap set as they are the best fitting to replace the old Black Elcaps. The space allocated for the many Elcaps is rather restricted so one is best to use them.

As far as the model naming is concerned, the Mk IV is a evolution of the "Original", "Professional Monitor" that had a version 2 and 3 and then morphed into the "Reference Standard Professional Monitor" (RSPM) that is the
Mk IV.

I guess amongst us IMF users the term "Mk IV" was the abreviated name used to identify this model opposed the full model identification name.

Effectively there were two major changes during the Mk IV's lifespan which were the driver line up changes and thus they were the MK V and VI but they were never called those names officially, then the next change became the RSPM Mk VII that had a completely different driver layout with the midrange being up above the tweeters.

Which driver combination do you have ? the Elac / Celestion combination (Mk V) or full Elac line up (Mk VI) as both these variants were officially named MK IV "Improved".

Also as you are a new member, may I ask which country you are located in ?


Cheers.

Hi and thanks for your reply,
maybe because of my poor English, I do not completely understand "Sadly the type of people it has attracted is not what most sensible level headed people want to be associated with".
I'm part of that group just because I'm an IMF owner and I found a lot of information and shared materials from other users.

However, maybe this is not also the right place to talk about that :)

I didn't know that there were different models of Mk.IV.
How can I check which are mine? Is it possible to understand it from the serial number?

Best regards.
Luca
 
Hi Luca,

Yes during the timeline of Mk IV production there were a number of running changes made. Some where dependant on the destination of the speakers while others were purely upgrades that were made from learning more about the product while it was being produced over a number of years.

The best way for us to give you a better idea would be for you to post up some photos of them. Only then can we inform you of what you actually have.

BTW can I ask you again, what country are you located in ?

Cheers.
 
Hi Luca,

Yes during the timeline of Mk IV production there were a number of running changes made. Some where dependant on the destination of the speakers while others were purely upgrades that were made from learning more about the product while it was being produced over a number of years.

The best way for us to give you a better idea would be for you to post up some photos of them. Only then can we inform you of what you actually have.

BTW can I ask you again, what country are you located in ?

Cheers.

Hi,
I'm based in Italy, Milan.

Here is mi IMF!

Best regards.
Luca
 

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Hello Luca,

Your Mk IV is exactly the same variant as mine which is probably the best version of this speaker. This is basically the Mk V (unofficially) which uses the following driver units,

128/20 Elac Bass
5/36 Elac Midrange
HF1300 Celestion Tweeter
HF2000 Celestion Super Tweeter

I've always preferred the Celestion top end opposed to the Elac drivers that eventually replaced the Celestion units and then made the speaker become the Mk VI (unofficially ofcourse). There were also minor changes made to the Crossover board during the evolution process of this fine speaker system that still stands the test of time. Most of the changes were capacitor values. That's one of the reasons why you should always buy the replacement kits from Jerry at Falcon Acoustics in England. With these kits you'll get all the capacitor values (with a few extra in case yours had the slightly different values installed) to exactly replace yours and thus keep the specifications exactly as they were when they left the IMF Factory.

Cheers.
 
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These are some before after shots of one of the Crossover Boards after I replaced all the caps. I ordered the "Higher tolerance" matched set which is at a slightly higher cost, but if you are going to go to all the effort of doing this then do it properly I always say.

Before with only one cap removed before I thought of taking any photos.



And the finished item in the two photos below.



The only thing that is not showing on the above finished item is that I straightened up all the white square blocked resistors so they sit picture perfect.

I've also put hot glue into all the valley's between the blue Alcaps that sit tightly against each other. This is only done due to each alternate caps sitting up substantially higher than the original Elcaps and are on much longer legs and thus those are being subjected to sonic vibration that would have the longer legs suffer from fatigue and fail over time.
 

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Hi,
I'm based in Italy, Milan.

Here is mi IMF!

Best regards.
Luca

What you have is an RSPM Mk IV with an upgrade kit. Back in the day, owners could purchase and have dealers install an upgrade kit to make them into the 'Improved' model. However like IMF_Pioneer said, yours have the 'Improved' serial number so they might have left the factory that way. This is evident because you have the 'Improved' sticker below the model name on the metal plate. Also, they came with only the woofer, mid, and crossovers which is why yours have the Celestion tweeters and not the Elac tweeters.

Regarding recapping, I think it is a great idea because in my personal experience on my Mk IVs, it made a very noticeable improvement. I also went with the Falcon Acoustics kit. Why go with their kit? It is the most like the original parts, because they are manufactured very similarly to the original parts. Capacitors all have different properties, even within the same type of capacitor, so it can be important to maintain that as much as possible. Also, the cost of the kit is not too high.
 
What you have is an RSPM Mk IV with an upgrade kit.

Sorry to say, but ......." Incorrect ! "

Back in the day, owners could purchase and have dealers install an upgrade kit to make them into the 'Improved' model.

Absolutely Correct


Luca has already clearly stated that his Mk IV's are "P" prefixed models and thus this signifies that his left the factory as "Improved" models and not updated units as you stated in your post. Also you've confused the issue here as the "Improved sticker" was indeed supplied to owners that bought upgrade kit to fit onto the front panel. The location of this sticker is normally in a oddly placed space and thus also is a giveaway that the unit has had the upgrade kit fitted by an owner or dealer. The genuines had the sticker placed in the identical location in all the factory made sets.

As I clearly stated the "P" prefix in the Serial Number is the only way to identify whether a set of MK IV's are genuines from the factory or just earlier units dressed up.

BTW I have no issue with the earlier ones being dressed up as it was most certainly an improvement but the next instalment with the Celestion top end being replaced with Elac drivers wasn't a favourite of mine as I've A/B'ed a set of Elac top end units alongside a set of Celestion powered Mk IV's Improveds and I felt the Elac top end was a tad on the thin side, but this is merely a personal preference of mine as everyone's ears are different.

While I remember, both updated versions, that being the Elac top end and also the Celestion top end variants were denoted as "Improved". Both variants had the "Improved" sticker placed on the front lower panel.

Cheers.
 
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Sorry to say, but ......." Incorrect ! "



Absolutely Correct


Luca has already clearly stated that his Mk IV's are "P" prefixed models and thus this signifies that his left the factory as "Improved" models and not updated units as you stated in your post. Also you've confused the issue here as the "Improved sticker" was indeed supplied to owners that bought upgrade kit to fit onto the front panel. The location of this sticker is normally in a oddly placed space and thus also is a giveaway that the unit has had the upgrade kit fitted by an owner or dealer. The genuines had the sticker placed in the identical location in all the factory made sets.

As I clearly stated the "P" prefix in the Serial Number is the only way to identify whether a set of MK IV's are genuines from the factory or just earlier units dressed up.

BTW I have no issue with the earlier ones being dressed up as it was most certainly an improvement but the next instalment with the Celestion top end being replaced with Elac drivers wasn't a favourite of mine as I've A/B'ed a set of Elac top end units alongside a set of Celestion powered Mk IV's Improveds and I felt the Elac top end was a tad on the thin side, but this is merely a personal preference of mine as everyone's ears are different.

While I remember, both updated versions, that being the Elac top end and also the Celestion top end variants were denoted as "Improved". Both variants had the "Improved" sticker placed on the front lower panel.

Cheers.

You missed my point, and that's OK.. it wasn't very clear to begin with. I was trying to say that the Mk IVs he has are identical to a pair that has been upgraded from a pair of original Mk IVs. Regardless of if they left the factory like that, or if they were upgraded after the fact, makes no difference. They are one and the same. If they are factory Mk IV Improved's then obviously there is a batch of them that were in the transition phase between the Mk IV phasing out, and the Mk IV Improved coming in.

Regarding the ELAC vs. the KEF/Celestion drivers, I always looked at the Elac's being a measure to increase profits and lower production costs. They were good quality drivers but I cannot see them matching the KEF's in performance. If it were me, I'd do away with the Elac woofer and mid and just buy the reproduced B139 and B110 that are currently available..
 
If they are factory Mk IV Improved's then obviously there is a batch of them that were in the transition phase between the Mk IV phasing out, and the Mk IV Improved coming in.

I'm not sure if I can understand the above statement. There are the original format Mk IV's that use a full complement of KEF drivers and then they changed to the first of the "Improveds" which were an Elac / Celestion combination, followed by the second version of "Improveds" with those having the full Elac complement of drivers. I have posted up some images of all 3 variants plus a Dealer / Owner upgraded set (image 4) so that this eliminates any confusion.






The Original RSPM Mk IV using all KEF drivers, comes complete with Metal Stands. (stands not pictured)







The First issue of the " Improved" RSPM Mk IV variant using the Elac / Celestion Line up of drivers, complete with Timber Stands
( Mk V unofficially )







The Second and Last issued variant of the "Improved" RSPM Mk IV using the full contingent of Elac only drivers, complete with Timber Stands. Note the totally different Tweeter that replaced the HF1300 with the large face and also the sharper cleaner looking Super Tweeter that replaced the HF2000. ***Please Note that the reticulated Foam inserts are missing from the outlet ports. These all eventually break down and crumble, thus you can see the reminants still attached with traces of adhesive used.

( Mk VI unofficially ) thus why the next variant of the RSPM was the Mk VII (7)








The following image is out of production sequence and of an original RSPM Mk IV with a dealer fitted "Improved Kit" installed.
Note there is no "Improved" Decal fitted and also this set has the earlier Green mesh in the outlet ports which signifies that this was originally a KEF / Celestion fitted set.
**Note HF2000 Super Tweeter grille is missing. (common issue)







And Lastly,

The RSPM Mk VII (7) Note the change of the Midrange and Tweeter inverted line up and also the face of the Tweeter is different (reduced in size) to the last issued Mk IV "Improved".

Thank you to member Tor-S for the image used below.

 
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Hi there, I'm new here. Since yesterday I have a pair of IMF TLS-50 MKII speakers. They're in a fine condition and sound fabulous! Verry happy with them.

IMF_TLS50_II.jpg
 
Hi joyoo72,

The TLS-50 is a good introduction to the IMF Range.
Once you're hooked I'm sure you'll want to venture on to the TLS-80 or RSPM Mk IV's

These certainly are an addictive brand of speaker.

Cheers,
IP.
 
Hey. Puny little CM3a owner and proud of it. Incredible boxes and represent the smallest speakers i regularly listen to. See a pair of TLS 40 for sale close to me asking over 3 bills, and I am already speaker Heavy and have other adult $$$ obligations boring me to death. That being said I’ll probably dind a way to end up with them. For now here is pic of my garage sale find find.
 

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Hi joyoo72,

The TLS-50 is a good introduction to the IMF Range.
Once you're hooked I'm sure you'll want to venture on to the TLS-80 or RSPM Mk IV's

These certainly are an addictive brand of speaker.

Cheers,
IP.

Hi IMF_pioneer.

Thanks, for now I will keep them. I only need to move them to my own room. The GF thinks they're to big....
The WAF is low, the WAF of the 80 is probably lower
 
Yes WAF is relatively low, you should try owning both TLS-80's and RSPM's at the same time along with a myriad of the smaller models as well. I get hammered all the time.



To Diesel66,

The CM3a is a superb speaker if space is at a premium. I have a set of the "a" variants also and they are connected in conjunction with a set of Super Compacts and sound brilliant running in tandem at the same time with my Pioneer SX-1050 Receiver.
 
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I have started re-building my early "The Studio's". DO you all think I should go straight stock? Or, should I make whatever improvements I can?

More specifically I have thought about the following....
  • Moving the crossovers outboard
  • Modifying them to be bi-wire and/or bi-amp capable
Also, everyone says the inductors on the crossovers are too close and should not be parallel layout. But, I wonder if they were voiced with that layout and changing their orientation would change the crossover points?

Thoughts?
20181008_202631.jpg
 
Do you have all the same units like the tls 50 mk-1 have or different. I put pictures of my crossover,the is one of the last version before switching to the mk II,it long time ago,2 years?
 
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