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IMF owners thread!

Hi,like I said to my knowledge the IMF reference standard are exactly like the improved MK III except change to foam inside the cabinet,no bottom plate and no affiliation with RSPM,no foam grill,clothe material,probably you could have beige or black (vynair grille ?).The picture I saw have black baffle with celestion and kef,old race track woofer sp6171 but maybe,later version sp1044.Year should between 74-75-76,hard to say.You know no number or other way to say MK I,MK II,MK III,only at the time the IMF original description booklet with the change made at the new model.The different reviews made at the time should help,but hard to find.Yvan
 
Good info, Thanks. The model I heard in 1974 was simply only badged IMF "Reference Standard" on the front with nothing else. It seems this is the same speaker described.

The other speaker we exchanged about - the "Domestic Monitor" is discussed on the imf-electronics site - clic>Professional Monitor>ON TEST (IMF) Review. Clement Brown wrote about Domestic Monitor December 1970 in HI-FI SOUND. On the imf page, he compares it to the Professional Monitor in top, middle & especially bottom of article.

Also, simply amazing the Professional Monitor III attained all the way down to 10 Hz - ? may be the lowest for any IMF ? I think you have compared the PM III to the RSPM MK IV ? and sorry if redundant, but if compared, what were your sound impressions ? What sounded different ? Curious. I think it is written either in this thread or other AK threads in comparison.
 
Hi, depending of your entourage and HI-FI audio dealer,all my friend have Crown some DC 300A,some DC-150,Preamp Crown or preamp Dayton Wright SPS MK III or SPA.I did try Treshold amp,some friends Marantz 250,500 with preamp 3300.Never try all the above amps you mention.My friend when he sold me the MK III get a pair of Magnaplanar 1.6,they sound very natural not to much bass extension matching with the Bryston 3B,with preamp Dayton wright .After he change for Nad with NHT speaker,it was okey.Me I stick with the MK III.Yvan
 
That Mk III is a real keeper for sure. Low pipe-organ notes must vibrate home foundation to "feel" the notes at different vibrating resonances, as it gets down to 10 Hz. I do like my RSPM MK IV and will keep them, they are not my best speaker - have 3 other types near or equal to it, but different and then also one greatly topping it. Mention that only as it stresses how great IMF are in keeping them forever. The IMF sound is wonderful & a life-keeper.

That run-off of Maggie 1.6 vs IMF is really something to hear. I wonder if he played them against each other ? The Maggie surely needs an extremely fast subwoofer matched to it (ex: Rythmik, REL) for an honest comparison. Of note - many owners of the current itteration - Magnepan 1.7 are selling them like crazy right now since the new 0.7 (or 7 nomenclature) was recently just released. Both are great - the 1.7 may be too large for many rooms -folks wrote in to Maggie for a downsized version sporting all the same sonic attributes -and the 0.7 came out now. It fits better in rooms, as is somewhat smaller, and the 0.7 and 1.7 Maggie both need that sub or paired stereo subwoofers (better) for full-range, so folks are changing now to 0.7 New owners also save money this way. For the past few months I never saw more 1.7's up for sale - literally a couple new adds every week, like never before. I bet the 0.7 is being bought a lot. Both are great !
 
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hi,the Maggie 3.7 are suppose to be one of the best of their products.The big improvment I made is put high quality film capacitors (mundorf .47uf silver-gold-oil) have lead silver solid wire+ the 12uf and 6 uf (kimberkap) have lead copper strand wire, now the sound is like 3D,lifelike,love it and still the same balance overall + Cardas speakers post (copper).Spend $350.00,worth it.Do Alcaps use copper as lead material,this make all the difference.Yvan
 
Hi, IMF Reference Standard came after the mk III improved and before they stop production, IMF consider them with the mention of being "reference standard".At the time not to many other brands could compete,You know the SACM suppose to go to 7 hz,but the sound they say is very dull?They have all the components in straight array and not group together like the Prof.So the image should be very different.Yvan
 
I'm thinking now what I heard in 1974 IMF "Reference Standard" was a different model than we're exchanging on, but that same one in the pinkfish thread, just based on dates. A lot of models overlapped dates selling together at same time. What I heard originally was in 1974.

The RSPM came along later (emerging ? 1975-6 maybe ?), but just shortly after that "RS" model, and said as such on pinkfish. Then the Professional Monitor I thru III emerged after the RSPM. But, the imf-electronics site timeline puts the PM emergence at 1981. If the Reference Standard model was a variant of the PM III, how could the dates align ? I'm mixed up.

The pinkfish thread corresponds with what I heard dating 1974, calling that model simply "Reference Standard". Is it that before the RSPM, IMF produced the Reference Standard very shortly, abandoned it until later, picking up the RSPM instead...then moving to the Professional Monitor as a spin-off of the 2 jumps backward Reference Standard model ?

On imf site it says PM was developed off of RSPM, so the dates don't align if so; how would you put these models in the timeline without a #date, just -first to last ? what order ? Reference Standard, RSPM, Professional Monitor I, Professional Monitor II and Professional Monitor III ?

The pinkfish mystery model I heard, same model as Robin Marshall owning the Reference Standard in 1974 precede the RSPM by 1 or 2 years.

What do you think about the alignment of dating for the models as they first appeared ?
 
Furthering the confusion, John Hayes stated when IMF started they manufactured "the original professional monitor", but don't know if that meant in application - I think so ( as opposed to say a home hifi speaker of the time ), or the actual name of the model of loudspeaker.

I think the name of the very first model around 1968 was called IMF Monitor.

So, what pinkfish, Marshall & I heard was a badged IMF "Reference Standard" labelled model somewhere between 1968 to 1974, which we heard in 1974. I wonder if Hayes, Bliss and Gibson are still living, they could clear up this model from 1974.

To relate something really weird, but seen by many & very true, actually crosses into the Fried brand speaker line, both Fried & IMF sold around my area at the same time. In the early 1970's when Fried issued the 1st Model R series I ( I own this model) -it was also sold around here completely badged as both IMF and also as Fried (mostly Fried) - either way ! I saw & heard the new-selling (early 70's) IMF-badged model R just shortly BEFORE before we saw the Fried same R around here-it was nearly identical (cosmetics differed) & priced just a bit more. Some have written about IMF-badged R's on the web, because they either owned them originally or heard them in the showroom. It's possible this is when the 2 companies were going thru opposing times. It's very rare to find an IMF-badged model R - it may be a total Fried product that borrowed badging & labelling (seems that way). The cabinet finish & grills & badging were different. The drivers (and probably everything inside) were identical. Yet, there is never mention of it on imf-electronics or the yahoo group, or from IMF purists. It is strangely ignored as if not wanting affiliation with Fried's own model. It exists - I have seen them for sale (only 3) long after seeing them in the shop selling new back in 1970's & they go for more than Fried R's from just oddity or rarity of badging. People are NOT gluing IMF badges on -the grill cloth looked slightly different - Fried was deep dark black, IMF a shade lighter brand new. Fried cabinets were much darker wood-finish, IMF used their traditional finish we all know (lighter than traditional Fried '70's finish which is darker). It all corresponded. But some shysters may try that used-selling trick.

It may also be because right near me is Philadephia, PA, USA (1 hour away) where IMF had a US warehouse, possibly an off-shoot factory (on City Line Ave, Philly) ? maybe offices ? and Fried's headquarters/plant were also only a couple miles away from there. This may explain the interchange of materials, and also why an unusual model was seen in this area - maybe trial production runs ? The Emmaus "Sound Advice" audio shop 1 hour from Philly sold that IMF "Reference Standard" and then also carried the IMF Super Compact there too at the same time -the SC were on the side wall for demo - which 2 of my friends bought (and me much later series II SC). Fried was sold at another shop about 20 minutes away, where my buds bought Fried R's series I and then II series later.

There was some strange Fried-IMF crossover in some models sold, but possibly IMF purists aren't aware or may not like to acknowledge. It's neutral to me, owning both brands (3 sets total). The pursuit was for a similar sound, so much respect for both. It gets weird with crossover models - I'm only aware of the R's, but maybe the Fried guys have seen others. The R crossover was known well here -because - we were young & all remarked how we could get the Fried a bit cheaper ! Probably about $50 difference brand new back in early '70's -which was a lot of difference for young folks then, hence my buds bought the Fried R. The two badged models sounded exactly the same. I got my R's used years later. At that time, the only brand new IMF we could afford were Super Compacts, and they were a reach at that age back then ! The IMF were not inexpensive new back then -they were high priced, but not the ultimate highest brand price. I know IMF had the Michigan offices, and I think it all later ended in Philadelphia -but not sure about that.
 
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Question for LVMUSIK
As i understand you have a Pro Monitor mk III and RSPM
mk IV? I have Pro Monitor mk III and can buy RSPM mk IV
improved. Is it worth to go for it, or should i stick to my Mk
III. Rspm improved are a bit newer and have different drivers
and crossovers, but do they Sound better than Pro Monitor
mk III? Any help welcomed, as i want to make sure that
i get a better sound with Rspm's before i pull the trigger.
Otherwise, if they are not a improvement soundwise i can spend
money on better amp instead for my Pro's mk III.
 
HI,You are confuse,1971-1972 prof. MkIII,improved around 73-74, 1974 reference standard, later exactly? Maybe Canuck know probably more than me RSPM mk 4 Maybe around 1976-77-78? Myself I have never see a pair of reference standard here on Montréal,how many pair sold?probably most of them Europe,maybe Johann from forum IMF website should know from Netherland,I know he has collected many serial # of different model to have an approximative idea of how many sold IMF in different country.Yvan
 
luvmusik said:
I'm thinking now what I heard in 1974 IMF "Reference Standard" was a different model than we're exchanging on, but that same one in the pinkfish thread, just based on dates. A lot of models overlapped dates selling together at same time. What I heard originally was in 1974.

The RSPM came along later (emerging ? 1975-6 maybe ?), but just shortly after that "RS" model, and said as such on pinkfish. Then the Professional Monitor I thru III emerged after the RSPM. But, the imf-electronics site timeline puts the PM emergence at 1981. If the Reference Standard model was a variant of the PM III, how could the dates align ? I'm mixed up.

The pinkfish thread corresponds with what I heard dating 1974, calling that model simply "Reference Standard". Is it that before the RSPM, IMF produced the Reference Standard very shortly, abandoned it until later, picking up the RSPM instead...then moving to the Professional Monitor as a spin-off of the 2 jumps backward Reference Standard model ?

On imf site it says PM was developed off of RSPM, so the dates don't align if so; how would you put these models in the timeline without a #date, just -first to last ? what order ? Reference Standard, RSPM, Professional Monitor I, Professional Monitor II and Professional Monitor III ?

The pinkfish mystery model I heard, same model as Robin Marshall owning the Reference Standard in 1974 precede the RSPM by 1 or 2 years.

What do you think about the alignment of dating for the models as they first appeared ?
Click to expand...

Luv'r... maybe we need to clarify between the "Professional Monitor" and "The Monitor". The Monitor was very early in the mix for IMF... probably 1969 - 1972. And the predecesor to The Monitor was "The Studio", which I think we have pegged around 1967-68. There is more info here, and we discussed this model considerably under a thread I've lost right now.

Now what I find interesting is this piece as part fo the IMF Marketing info for the Studio... a "Ribbon" Monitor? What was that all about? :scratch2:

Why We Developed the Studio Loudspeaker

Perhaps you are already acquainted with us and our long term involvement in "state of the art" phonograph cartridges, tone arms, and loudspeakers. We might mention the English corner horns, the American push pull electrostatics, the first full range electrostatic, and the first plastic cone loudspeakers - all of them models in their day of advanced design.

Eight years ago we first described a unique concept in loudspeakers, the transmission line (cf. Newsletter 4, Sept., 1962), a new laboratory tool for evaluation of advances in record reproduction, replacing the full range electrostatics that were not capable of reproducing the vastly increased dynamic and frequency ranges of 1962's improved records.

Five years ago we first used our "Ribbon Monitor" at public demonstrations of advances in record reproduction (cf. Newsletter S). This we did despite the prevailing industry opinion that "the public isn't ready for an `honest' loudspeaker," or "the public does not like a flat frequency range." Notwithstanding, at least part of "the public" was enthusiastic about the Monitor, and seemed to be ready for "honest," "flat" loudspeakers.

The Monitor is expensive, large, and scarce. What was needed, we thought, was a moderately sized and priced loudspeaker containing the basic operating principles and performance of our laboratory tool; one that could be made readily available to the part of "the public" which obviously is ready for a standard of reproduction that the industry says "the public" is not!

Thus, after a long research and developmental program, we present our STUDIO Transmission Line Loudspeaker. We will describe it in some detail, just because it differs so markedly in concept and execution from what has heretofore been available to the home music lover.

front.jpg
 
Those early ones are tricky to peg. I have the one in the above image, minus the cross over panel. Someone recently picked up a pair similar to the above image, crossover wires exposed but at the panel location, however with different driver configuration.

What I find funny about the age is that compared to other speakers of it's time, it is so good, even by todays standards. Most of my speakers are this vintage, sony, tannoy, IMF, and I keep coming back to the IMF, although the Tannoy golds do beat them in space and detail. Perhaps a tannoy OB with an IMF TL subs.
 
Luker, do You have the improved model?On previous posts I put some photos of MkIII X-over standard and MkIII improved and the serial # should be written on the Wood near the X-over behind the woofer.The MK IVcan handle bit more power.look more impressive,more adjustment control for different room,the MkIII midranges frequency begin at 375 Hz,MKIV 350 HZ, it means now the midranges take the place of the woofer between 350-375 HZ,more open sound because maybe the MKIII at that frequency the woofer can not give same open sound,bit darker in the same region,very subtil + the Kef B110 have bextrene (obsolete)cone, not so stable like the new material use in the MKIV (don't remember the material but have been developp by BBC around 78-79 IIRC) but still in use today.They have improved the woofer,more rigid,more faster,personaly I prefer the Kef, ferrofluid tweeter-Stw the MKVI metal dome?but the MKIII go lower 10 HZ compare to MKVI 17HZ. I found the bass,round and define, good harmonic in the MKIII excellent.Best regards,Yvan
 
The early IMF models are difficult to place exactly.

The very first model was indeed the "Professional Monitor". Whether or not it was called that at the time is tough to say. However, this was what was shown at an audio show where Bud Fried began to take orders for the loudspeaker and thus IMF was born.

It seems that in either the very late 60s or very early 70s, a "Domestic Monitor" and "the Studio" was produced, both being different than the Professional Monitor.

Not exactly sure on when the Professional Monitor mk II came out, and not sure on when the mk III came out.

However, the RSPM Mk IV is the "Professional Monitor mk IV", they just added "Reference Standard" to the name.

It's very possible that the "Reference Standard" model you are referring to was inbetween the Professional Monitor III and the RSPM Mk IV. That is my best guess.

Unfortunately without any of the original IMF folks around it's near impossible to really pinpoint what the history of this brand was.
 
canuckaudiog said:
The early IMF models are difficult to place exactly.

The very first model was indeed the "Professional Monitor". Whether or not it was called that at the time is tough to say. However, this was what was shown at an audio show where Bud Fried began to take orders for the loudspeaker and thus IMF was born.

Unfortunately without any of the original IMF folks around it's near impossible to really pinpoint what the history of this brand was.
Click to expand...


And I still want to know what the "Ribbon Monitor" was all about. Is that what they had at the show? :scratch2:

And now that I have gotten over my "senioritis" it was Federer's pair we were talking about here! C-atle references it as well.
 
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Luker74 said:
Question for LVMUSIK
As i understand you have a Pro Monitor mk III and RSPM
mk IV? I have Pro Monitor mk III and can buy RSPM mk IV
improved. Is it worth to go for it, or should i stick to my Mk
III. Rspm improved are a bit newer and have different drivers
and crossovers, but do they Sound better than Pro Monitor
mk III? Any help welcomed, as i want to make sure that
i get a better sound with Rspm's before i pull the trigger.
Otherwise, if they are not a improvement soundwise i can spend
money on better amp instead for my Pro's mk III.
Click to expand...

I posed same question on post #702, and think it is answered somewhere in this or a similar thread. For these 2 related brands, I have IMF RSPM MK IV, IMF Super Compact II, and Fried Model R series I. So, don't know answer, also curious.

The Professional Monitor III reaches a low 10 Hz, and the RSPM has a very versatile control switches with very many possible settings combinations to tailor the sound to most rooms. 3 controls each having 3 settings yields many combinations.

Great question, I also wonder the same question you asked. Post #714 has some answers for it.
 
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I believe exactly as posted in #715 and always have, but what recently confused me is the timeline & a model description on the imf-electonics site.

What model is the Professional Monitor which very later emerged in 1981 ? it shares a link also to an even later Professional Monitor III. The PM model 1981 description says - "...new model is a derivative of the widely acclaimed Reference Standard Professional Monitor on which it is based." Made after RSPM.

Then clicking on nearby link for Professional Monitor III, the description says - "The Professional Monitor Loudspeakers were the first to be designed and produced by IMF Products in England."

This is where the confusion enters in the model name.

Was the very first model called "The Professional Monitor" and then the 1981 model called the "IMF Professional Monitor" (I, II, III) ?

I don't think "produced by IMF Products in England" is relating that statement to the original company name before it was called IMF.

This is where the very earliest original IMF speaker coined Professional Monitor gets all confusing with the ? same named ? Professional Monitor issued in 1981 ?

Seems for that name - it may be timelined for starting dates:

Professional Monitor 1968 very 1st speaker made, Professional Monitor MK III 1971-1972, mystery "Reference Standard" version sometime up to 1975, RSPM MK IV 1975-1976, RSPM MK VII 1976-1977, skip smaller models & SACM, then Professional Monitor 1981-1982 very last speaker made (other than 1 more year of CM-3A).

See what I mean, based on imf-electronics site timeline ? The 2 or more versions of Professional Monitors' models seemed to start 1968, and then far later end with the company, but maybe were not made 1971 to 1981.

How do we distinguish the very early speaker and the very late speaker with the same name to distinguish naming them ? Is their some nomenclature (like "earliest PM" versions, "latest PM" versions ) ? , to clear up the models confusion.

Maybe that 1st very speaker made was called "IMF Monitor" 1968, following up to IMF's timeline to 1971 Monitor II, to 1973 Monitor III, to mystery "Reference Standard" time to emergence of RSPM overlapping sales of prior Monitor III (around 1975-1979) and also overlapping far latest Professional Monitor (1982), selling at same time briefly. But if the very 1st speaker ever made was named "Professional Monitor" - we can see the confusion to the very last line-ending speaker model made by IMF with same name "Professional Monitor". Surely others have wondered about this very 1st and very last speakers made.

Note : the smaller CM-3A possibly closed the line in 1987 ultimately, left out of discussion to focus on large models discussed whose production ended in 1986.

What's the delineation ?
 
I'm pretty sure "The Monitor" preceded "The Studio" model. The article using "Ribbon Monitor" is indeed very interesting. Since it seems doubtful any Ribbon-microphone or Ribbon drivers technology was imparted to IMF design (? that we know of yet ?), I'm reading that word " Ribbon" to mean "Award", like securing a 1st place "ribbon" at a competition. Almost then, like synonymous to "Award-Winning Monitor" - which really makes sense as that very-most-earliest speaker was demonstrated at a show as the 1st few prototypes before real-production started. Maybe it also won an award at that inaugural show, thus deemed -Ribbon Monitor.

However, if IMF really explored Ribbon drivers at any frequency -if so - more likely mids & hi's as they embarked in T-line bass seeing stat limits in lo-frequency during that period, then...wow...? where could we be today ? That sparks much interest, say speculating a IMF prototype with T-Line bass under 20 HZ, using their technology for seamlees crossover technology smoothly into a true-Ribbon mid and hi driver(s). Now, that's something to talk about and dream of. Maybe they did look at it ? The ribbon technology existed at the time ! Maybe they toyed with ribbon voice coils. Far less likely is that if they did measurements of that very first prototype with a Ribbon-microphone for testing them, either in the lab or even at that show for displaying measurements - then it could associate name of ribbon to monitor, but that's a more distant association.

It is interesting & also wonder why it was termed as such, maybe it was just an early name like using any other name, such as say - "Absolute Monitor", "Audiophile Monitor", etc.
 
Question - did the absolute very 1st speaker made by the IMF guys (probably at the time of, or before naming the company) have a B-139 woofer ? I thought reading that it did, was it true, or some other round woofer ? The first B-139 emerged in 1962.
 
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