IMF owners thread!
- Thread starter canuckaudiog
- Start date
SimplySound
Kent Engineering & Fondry
canuckaudiog
On a quest for high fidelity
Thanks Doug!
So, the original supertweeter is an HF2000, not the Coles unit. However the Coles can replace the HF2000 in this application, I'm just not sure if crossover modifications would be necessary (likely) and if it needs to be padded down to match the response.
It probably sounds fine but something to keep in mind is to perhaps look into seeing what crossover mods (if any) are necessary to integrate the tweeter into the existing crossover.
Sent from my D5803 using Tapatalk
So, the original supertweeter is an HF2000, not the Coles unit. However the Coles can replace the HF2000 in this application, I'm just not sure if crossover modifications would be necessary (likely) and if it needs to be padded down to match the response.
It probably sounds fine but something to keep in mind is to perhaps look into seeing what crossover mods (if any) are necessary to integrate the tweeter into the existing crossover.
Sent from my D5803 using Tapatalk
Yes, that's my Monitors still on castors
.
Chops has Tls80's MkII, but starts building his own TL speakers
later this year.
Regarding crossovers, he didn't do any mods to them, as
his motto is to keep things as original as possible.
He had to rebuild them tough for a simple reason.
When he removed them they were simply broken in half
.Chops has Tls80's MkII, but starts building his own TL speakers
later this year.
Regarding crossovers, he didn't do any mods to them, as
his motto is to keep things as original as possible.
He had to rebuild them tough for a simple reason.
When he removed them they were simply broken in half
luvmusik
HOORAY !...ELECTRICITY !
This pinkish thread is a classic piece of imf info of all sorts referenced over the years, thanks for posting it here.
Almost halfway down the thread DSJR posts on 14-08-08 at 01:30 AM some information confirming a set I heard in the early 1970's which elusively seems to be lost in the historical archives.
He speaks of 3 models marketted possibly among at least 7 others, before the RSPM IV..which are the Domestic Monitor, the "Reference Standard" and the Professional Monitor, then later the RSPM IV emerged.
There are 2 of these models I am interested in - the Domestic Monitor, but more importantly - the "Reference Standard" model which I heard back then when they were sold new. I have a brochure of this Reference Standard model showing the speaker foto on front of brochure and unfortunately misplaced the brochure & have searched, but surely it is filed in storage & temporarly lost. This model may have been 1 of 2 different imf models that came supplied with beige (light tan) grill cloth covers.
If anyone ( ? Yvan ? ) has any info, details, fotos, brochures on the "Reference Standard" and also the Domestic Monitor, please post it here.
This Reference Standard speaker is the model in the pinkfish thread which states Robin Marshall of EPOS owned in 1974. I recall the sound of this model and it was very close to the RSPM IV, possibly better, but it is a different model, with either the same drivers or almost all the same drivers as I recall. Everyone who heard this model was flabbergasted & they were the forte of the shop selling them. Limited info has been discussed on this model, it seems no one knows about it. These were NOT Studios, TLS, Monitors, or Professional Monitors models. They were about the same size or bigger than the later RSPM MK IV model. I have only ever seen that 1 sole "Reference Standard" set, and then later bought RSPM IV as they were closest in sound to them. Any help greatly appreciated.
It may take a very, very, very long time, but when I do find my brochure it will be posted here !
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c-atle-79bay
Super Member
Has anyone here had the chance to compare IMF's to Nestorovics?
Thanks
Thanks
wtaylorbasil
Active Member
IMF owner Thread
"The Mark 4 and TLS80 II were on low frame stands, slightly angled back as I remember"
At the moment I have a pair of TLS80 Mk IIs. They have angled stands but they are not originals. The stands have casters on them. Will these casters add any colouration to the output sound?
your comments would be most welcome.
"The Mark 4 and TLS80 II were on low frame stands, slightly angled back as I remember"
At the moment I have a pair of TLS80 Mk IIs. They have angled stands but they are not originals. The stands have casters on them. Will these casters add any colouration to the output sound?
your comments would be most welcome.
SimplySound
Kent Engineering & Fondry
So you are saying that before the "Professional Monitor MkIII" and the "Reference Standard Professional Monitor MkIV", there was maybe a "Reference Standard MkII & MkI"?
I could see it... And I love a good challenge... so the search is on!!! :yes:
SimplySound
Kent Engineering & Fondry
OK Luv'r... you sure they weren't maybe an RSPM MkI or MkII... there was an evolution of that line as shown here;
IMF Professional Monitor MK1
IMF badged early variant of the RSPM REFERENCE STANDARD PROFESSIONAL MONITOR
Drive Units: Coles STC-4001G super tweeter
Celestion HF1300 treble
KEF B110 SP1003 midrange
KEF B139 SP6171 bass
Crossover Frequencies: 375Hz, 3.5KHz and 13KHz Frequency Response: 17Hz - 35Khz Efficiency: 96dB Power Rating: 40 - 100W Impedance: 4 - 8 Ohms Finish: Teak Enclosure Type: Transmission Line Dimensions (H x W x D): 40" x 20" x 18" Weight: 190lb,
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Sansui77
Khosaku Kikuchi's Grandson
In that picture, what are those speakers on the right?OK Luv'r... you sure they weren't maybe an RSPM MkI or MkII... there was an evolution of that line as shown here;
IMF Professional Monitor MK1
IMF badged early variant of the RSPM REFERENCE STANDARD PROFESSIONAL MONITOR
Drive Units: Coles STC-4001G super tweeter
Celestion HF1300 treble
KEF B110 SP1003 midrange
KEF B139 SP6171 bass
Crossover Frequencies: 375Hz, 3.5KHz and 13KHz Frequency Response: 17Hz - 35Khz Efficiency: 96dB Power Rating: 40 - 100W Impedance: 4 - 8 Ohms Finish: Teak Enclosure Type: Transmission Line Dimensions (H x W x D): 40" x 20" x 18" Weight: 190lb,
canuckaudiog
On a quest for high fidelity
Ah those are an AKers. I remember that rebuild, he did an amazing job on those!
I don't recall what the speakers on the right are but they are a kit build I think.
I don't recall what the speakers on the right are but they are a kit build I think.
luvmusik
HOORAY !...ELECTRICITY !
When I heard the "mystery speaker model" in 1974 it was only labelled & badged "IMF Reference Standard" with no other designation. There were no numbers (1 thru 7), and no MK IV - this specific set preceded MK IV.
They used SP1044 flat oval woofers, not sure if early or late version; can't recall if front controls or not, or if back controls. They exactly correspond with the same mystery "Reference Standard" model Robin Marshall founder of EPOS speakers owned in 1974 which are discussed in only that 1 post of the thread from a most-knowledgeable IMF'er. That was the year, as I do remember the 2 fellows I went with to the shop and we were all together hanging only in that year. It was either a 3-way or 4-way driver design. Either same @ size or larger than RSPM.
They may have been a limited run of a handful production only. Some of the most knowledgeable IMF folks in Europe have assigned numbers to the 3 predecessors to the RSPM MK IV (and type 5, and 6 up to known 7's)...but this mystery set is not one of those.
Previously, I asked 1 of the 4 European experts about these -he did not know. Currently, I have now asked a 2nd fellow about them & he most likely will ask the other 2 gentlemen.
The IMF workers around at the time (1974) know about this set I am describing which Robin Marshall owned. Thus, it appeared by chance on the pinkfish thread as "related" to a different model - the Professional Model IV - a different speaker. IMF workers posted on the thread. Best bet is we get info from an IMF worker around there in 1974 from our UK friends. The set I heard was at "Sound Advice" (an indy shop, not the chain) in Emmaus, Pennsylvania -east coast USA 1974, now long gone. These were probably imported to the IMF company site located in Philadelphia - 1 hour away from the shop.
I could jump on & register at pinkfish to ask DSJR - it is a really old thread recently posted on -but his specific post was long ago, wonder if he's still around. Might be best source for info. Some sellers may know of the model -but it may have been very limited production & a set may have been sent just to Philly. Not sure if or how many sets sold. I think the shop owner kept the set.
We do know IMF used beige (light tan) foam on certain very early grill covers from imf owners writing about it (at least 2 or 3 owners; total 3 or more sets speakers). I recall the mystery set "Reference Standard" had beige (light tan) cloth grills - popular as a period piece then (think AR, etc)...it is possible the only point in question is if the model did have the beige or if recalling 40 years back possibly had black cloth grill covers. When I someday find the brochure it will solve the mystery - I'm pretty sure the foto was with beige cloth covers -it was the whole front side foto 8 x 11", with data & info on back (1 page sheet). They were not Studios, Monitors, Professional Monitors, nor TLS.
I would hesitate to call this a MK I or MK II, because it was clearly only badged "IMF Reference Standard" on the front -nothing else (no "PM" - no Professional Monitor affiliation badged). But, so far digging has found little on this mystery set other than reading pinkfish years ago & again now. It was not a prototype, but a model for sale (possibly only a handful were made). I did find some handwritten paperwork where I listed some audio components (TT's, Reel Machines, etc) I was interested in dated 1974 and in 3 places "IMF Reference Standard" is listed - this was 2 years before RSPM were made.
Interesting, too, is the beige foam (not cloth) very early grills found on one other very early IMF model were distributed out of Philly. There is a commonly found brochure describing the foam grill with the IMF Philly facility printed at bottom of last page. I believe that may have also been the Formica cabinet series too, but maybe not, can look at that brochure -it's on the web somewhere.
Shop sellers may know if more than 1 set was distributed -best bet there may be a former shop owner selling IMF 1974 new from either Philadelphia or New York City locations. Some one person may know. EPOS speakers, I believe have always been in UK, not sure if Robin Marshall is still available to ask - he would certainly know, if remembering.
The pinkfish thread link re-sparked my interest in the "Reference Standard". Had read that thread years ago & gave up trying to find out until renewed now. Wonder if DSJR is still there to ask after 7 years later now - he did post 4 years ago most lately. Coincidentally, my own RSPM MK IV are listed at the very end of the thread from the previous owner 4 years ago.
I guess if we all strike out, the best sources are DSJR, Robin Marshall, an IMF 1974 worker from UK, a 1974 IMF high-volume seller near NYC or Philadelphia USA and the 4 or 5 IMF experts in Europe - haven't given up yet. PS, long ago a very knowledgeable IMF fellow in Europe thought there was no such mystery model (yet my brochure describing it is in storage), listing all the archive timeline models we are familiar with, but also stating there were no beige-foam grill models from the factory. We now know there was 1 model at least issued with beige foam grills from the IMF factory -it has been written about & I recall photos, too from some members that owned them who bought them new or intact as original said from first owner.
Maybe this "Reference Standard" was a very limited number of handful only in production. Any info, data, specs, fotos welcome.
They used SP1044 flat oval woofers, not sure if early or late version; can't recall if front controls or not, or if back controls. They exactly correspond with the same mystery "Reference Standard" model Robin Marshall founder of EPOS speakers owned in 1974 which are discussed in only that 1 post of the thread from a most-knowledgeable IMF'er. That was the year, as I do remember the 2 fellows I went with to the shop and we were all together hanging only in that year. It was either a 3-way or 4-way driver design. Either same @ size or larger than RSPM.
They may have been a limited run of a handful production only. Some of the most knowledgeable IMF folks in Europe have assigned numbers to the 3 predecessors to the RSPM MK IV (and type 5, and 6 up to known 7's)...but this mystery set is not one of those.
Previously, I asked 1 of the 4 European experts about these -he did not know. Currently, I have now asked a 2nd fellow about them & he most likely will ask the other 2 gentlemen.
The IMF workers around at the time (1974) know about this set I am describing which Robin Marshall owned. Thus, it appeared by chance on the pinkfish thread as "related" to a different model - the Professional Model IV - a different speaker. IMF workers posted on the thread. Best bet is we get info from an IMF worker around there in 1974 from our UK friends. The set I heard was at "Sound Advice" (an indy shop, not the chain) in Emmaus, Pennsylvania -east coast USA 1974, now long gone. These were probably imported to the IMF company site located in Philadelphia - 1 hour away from the shop.
I could jump on & register at pinkfish to ask DSJR - it is a really old thread recently posted on -but his specific post was long ago, wonder if he's still around. Might be best source for info. Some sellers may know of the model -but it may have been very limited production & a set may have been sent just to Philly. Not sure if or how many sets sold. I think the shop owner kept the set.
We do know IMF used beige (light tan) foam on certain very early grill covers from imf owners writing about it (at least 2 or 3 owners; total 3 or more sets speakers). I recall the mystery set "Reference Standard" had beige (light tan) cloth grills - popular as a period piece then (think AR, etc)...it is possible the only point in question is if the model did have the beige or if recalling 40 years back possibly had black cloth grill covers. When I someday find the brochure it will solve the mystery - I'm pretty sure the foto was with beige cloth covers -it was the whole front side foto 8 x 11", with data & info on back (1 page sheet). They were not Studios, Monitors, Professional Monitors, nor TLS.
I would hesitate to call this a MK I or MK II, because it was clearly only badged "IMF Reference Standard" on the front -nothing else (no "PM" - no Professional Monitor affiliation badged). But, so far digging has found little on this mystery set other than reading pinkfish years ago & again now. It was not a prototype, but a model for sale (possibly only a handful were made). I did find some handwritten paperwork where I listed some audio components (TT's, Reel Machines, etc) I was interested in dated 1974 and in 3 places "IMF Reference Standard" is listed - this was 2 years before RSPM were made.
Interesting, too, is the beige foam (not cloth) very early grills found on one other very early IMF model were distributed out of Philly. There is a commonly found brochure describing the foam grill with the IMF Philly facility printed at bottom of last page. I believe that may have also been the Formica cabinet series too, but maybe not, can look at that brochure -it's on the web somewhere.
Shop sellers may know if more than 1 set was distributed -best bet there may be a former shop owner selling IMF 1974 new from either Philadelphia or New York City locations. Some one person may know. EPOS speakers, I believe have always been in UK, not sure if Robin Marshall is still available to ask - he would certainly know, if remembering.
The pinkfish thread link re-sparked my interest in the "Reference Standard". Had read that thread years ago & gave up trying to find out until renewed now. Wonder if DSJR is still there to ask after 7 years later now - he did post 4 years ago most lately. Coincidentally, my own RSPM MK IV are listed at the very end of the thread from the previous owner 4 years ago.
I guess if we all strike out, the best sources are DSJR, Robin Marshall, an IMF 1974 worker from UK, a 1974 IMF high-volume seller near NYC or Philadelphia USA and the 4 or 5 IMF experts in Europe - haven't given up yet. PS, long ago a very knowledgeable IMF fellow in Europe thought there was no such mystery model (yet my brochure describing it is in storage), listing all the archive timeline models we are familiar with, but also stating there were no beige-foam grill models from the factory. We now know there was 1 model at least issued with beige foam grills from the IMF factory -it has been written about & I recall photos, too from some members that owned them who bought them new or intact as original said from first owner.
Maybe this "Reference Standard" was a very limited number of handful only in production. Any info, data, specs, fotos welcome.
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SimplySound
Kent Engineering & Fondry
Thanks Luv for adding detail to this. Seems we do have a mystery speaker sandwiched between the early "Studios" and the "Professional Monitors"!
The evolution of the IMF's at that time from 1967 to 1974 is very "dynamic". I could see an early variant that they called a "Reference Standard" that got rolled up into the Professional Line.
I too would like to see the specs and component group... the search continues! :thmbsp:
Yvan_donald
Well-Known Member
HI,IIRC The reference standard is a prof. MkIiI with foam,replacing the honey comb system(pink fiberglass).I saw a picture on Imf web site,from Stephane(owner of the web site and owner of The reference standard).Imf have probably develop The MkIII to their best at the time And consider them as ref. standard with original Kef and celestion components.Start producing their own mid and woofer,new STW,TW,for the new IMF.Yvan
Yvan_donald
Well-Known Member
HI, IIRC they did have the old racetrack Kef sp 6171 B-139.Yvan.
Yvan_donald
Well-Known Member
Hi, I have in my possession the review of IMF domestic import from March 1972 HI-FI news magazine.Dimension 40X19 3/4X17 1/2, frequency range 20hz-beyond 20khz.Wood veneer finish Teak or walnut,black Formica back with 2 control mid and hf +-2db.They say they are not in the prof.categorie,smaller in size.No aluminum trim,on castors,look more like Tls 50 MK I, weight approx.140 pounds.This mystery reference standard had the same grey spiral foam at the outlet of TL like IMF TLS 50 MK I.The picture of IMF with the other speaker look like the domestic monitor,but someone modify the bottom edge + the castors are not genuine IMF,that's for shure.Yvan.
Yvan_donald
Well-Known Member
Hi,I have look at the pinkfish media thread,at the time crown amp was the most use amp and I use to have to DC-300A bridge mono to drive my Prof.MK III with my same Audio Research preamp + I even have the optional heatsink install on these amps + two wisper fan on each (still have the heatsink) but not the amps.Believe me the woofer never woble.At the time Classe amp,Treshold,Audio Research could have drive the IMF without any problem,and for shure they where better than the Crown but expensive.The first Bryston 3B and second generation 3B have a better sound than the Crown,only on lower organ note >20hz. (woofer wobling) or big classical passage the green light became red. But the 3B-ST never clip and the woofer never woble on any big music passage with a very good control,tight bass and extremely natural and musical.The bottom much more define than his predecessor.If someone like to buy an old Crown,this is not a good idea,today many amps are much better.Best regards,Yvan.
luvmusik
HOORAY !...ELECTRICITY !
Hi Yvan, had a feeling you had seen these "Reference Standards" or a foto of them! That must be the one, and especially if ST owns a set, it could be limited production.
How many do you think were made ? Did the foto you saw show only "Reference Standard" only words in the front badging or back labelling, without any numbers like I, II, III, etc ? Any way we can see that foto ? What years do you think the "RS" was made ? If the "RS" was around the time of Professional Monitor & PM III timeline, preceding the RSPM, where do you think it fit in timeline-wise ?
Do you recall if the foto showed usual black or beige (light tan) color grill cloth covers, or foam grill covers ? Wonder if ST has the specs for "RS" model ? Were any controls on the front or back ? I thought if any, they were on the back for the "RS". Did the "RS" have the early or later SP1044 configuration if you recall ?
This must be the one !
How many do you think were made ? Did the foto you saw show only "Reference Standard" only words in the front badging or back labelling, without any numbers like I, II, III, etc ? Any way we can see that foto ? What years do you think the "RS" was made ? If the "RS" was around the time of Professional Monitor & PM III timeline, preceding the RSPM, where do you think it fit in timeline-wise ?
Do you recall if the foto showed usual black or beige (light tan) color grill cloth covers, or foam grill covers ? Wonder if ST has the specs for "RS" model ? Were any controls on the front or back ? I thought if any, they were on the back for the "RS". Did the "RS" have the early or later SP1044 configuration if you recall ?
This must be the one !
luvmusik
HOORAY !...ELECTRICITY !
Great point about the Crown amps - we used them a lot back then -good power for good dollars, and tried them on many speakers. DC-300 and D-150 both damped at 200 df. The G.A.S. Ampzilla I & II damped at 150, but Son Of Ampzilla (good IMF match), which I use now, damps at 500. Figures are all minimum damping, may go higher. The Crown did cross between home-audio and Pro-Sound/Sound Reinforcement applications, as did Phase Linear & ESS. Some felt it slightly harsh, maybe bright or a hint of metallic, but I think it had to do with pairing of speakers a lot.
Cool you had tried those great vintage amps as combinations and today there may be more so many more great amps to choose from. Regarding vintage amps - have you heard any results from folks with IMF trying - Dynaco, Harmon Kardon, ESS, Sony, Marantz, Phase Linear, Epicure or ESS best line of their amp offerings ? Sumo & SAE were take-offs of G.A.S. from James Bongiorno. I thought reading Dynaco ? may ? have paired well, but they had lo-damping factor & we're back to that woofer excursion problem again probably. We know Quad did pair well with IMF.
Cool you had tried those great vintage amps as combinations and today there may be more so many more great amps to choose from. Regarding vintage amps - have you heard any results from folks with IMF trying - Dynaco, Harmon Kardon, ESS, Sony, Marantz, Phase Linear, Epicure or ESS best line of their amp offerings ? Sumo & SAE were take-offs of G.A.S. from James Bongiorno. I thought reading Dynaco ? may ? have paired well, but they had lo-damping factor & we're back to that woofer excursion problem again probably. We know Quad did pair well with IMF.
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