I thought the Fried Model H was a <very> good speaker but I thought the big IMFs sounded tubby and wooly--nice highs and mids but the bass threw me off. These were my impressions at the time, I haven't heard these speakers since they were new.
IMF owners thread!
- Thread starter canuckaudiog
- Start date
canuckaudiog
On a quest for high fidelity
Your account of IMFs like this isn't the first I've read. However, I haven't heard that presentation in my experience so I imagine there was something else going on there. If the bass sounded like that, I definitely wouldn't be such a fanatic about them. :yes:
Hopefully one day you'll get to have a chance to experience what the incredible, articulate bass from an IMF is really like. I recall when a gentleman who was offering a pair of Carver separates to me (M1.5t and C4000) came over to try them out on the IMFs, his comments were "Wow, I've never heard IMFs sound like this before. When I heard them new in the 70s they were very slow in the bass regions making them sound bloated and muddy. These sound clean, quick and articulate."
Those carver separates were a wonderful pairing with the IMFs. I am still kicking myself for letting those go!
sheltie dave
Addicted Member
Tom, the MkIIs had a little different rock wool formulation, and the Hs were quite, quite good.
I picked these up from an estate sale where I submitted a low bid. Didn't hear anything for two months, and then suddenly got a call out of the blue asking if I still was good for paying the bid amount. Other than being in San Diego and the speakers being in St. Louis, I was good to go and a friend picked them up the next day.
They are supplanting a pair of Thiel Cs1.2s in the family room, to my wife's dismay, but I really like the bass. They aren't nearly as bloated as the AR3s were in the same spot, but not as nimble as the KHorn bass. The best part is I can't hear the box, and they are more efficient and hit heavier than the Vandersteens that were under consideration.
I picked these up from an estate sale where I submitted a low bid. Didn't hear anything for two months, and then suddenly got a call out of the blue asking if I still was good for paying the bid amount. Other than being in San Diego and the speakers being in St. Louis, I was good to go and a friend picked them up the next day.
They are supplanting a pair of Thiel Cs1.2s in the family room, to my wife's dismay, but I really like the bass. They aren't nearly as bloated as the AR3s were in the same spot, but not as nimble as the KHorn bass. The best part is I can't hear the box, and they are more efficient and hit heavier than the Vandersteens that were under consideration.
JimPA
Distinguished Member
The IMF designs were more heavily stuffed in the last fold of the T-line compared to the Fried designs.
Having the last fold of a T-line too heavily stuffed will cause impedance peaks in the lower frequencies
This could account for Tom's observation as a tubby wooly sound.
The Kef B139 was not the beast choice for use in a T-line.
This driver has a heavy cone mass and large Vas which made it best suited for a closed box.
canuckaudiog
On a quest for high fidelity
I think you might be thinking of a different driver Jim, everything I've read about the B139 states that it has a lightweight cone, which is part of why it bottoms out in t-lines.
I agree it is not the best t-line driver out there, but there is a reason it was used in transmission lines.
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JimPA
Distinguished Member
The moving mass of the Kef B139 is 54 grams.
The stock Dalesford 10" moving mass is 35 grams.
The specs for the moving mass of the Fried oem Dalesford 10" I do not have.
Below is a Dalesford spec sheet for their stock models.
The oem Fried versions have a different voice coil geometry and larger magnets compared to the stock versions
I am using this as a reference to illustrate my point that the Kef B139 drivers have a heavy cone mass.
The main reason the Kef B139 driver was used for a T-line was due to it's high compliance compared to the other drivers available back then.
http://p10hifi.net/TLS/drivers/images/B139B_newer.gif
http://audiokarma.org/forums/attachment.php?attachmentid=330525&d=1329620902
Hi,the B139 because of is styrofoam cone (solid block),it have the flatest,no distinctive sound coloration and the best to achieved what is use for,reproduce low frequency,the weight of the cone is okey and this woofer is fast enough to make you feel any music instruments at any lower frequency.no fla fla just the right tonal sound.I'm very satisfied with my IMF and hope many membe'sr thing the same,good listening to all.
luvmusik
HOORAY !...ELECTRICITY !
IMF RSPM MK IV for sale today on ebay (no affiliation). Not sure of reserve price. Possibly nicest set of these ever seen other than when they sold new decades ago. Mentioning as someone near Meridian, Idaho can pick up, or he will ship (expensive). Maybe these are selling from an Ak'er, or hopefully an AK'er will get them. These need no work at all, which is a blessing and the best way to go; what we all wished was ours; the tops may have some water spots only. Beautiful condition. No bids so far, he opens at $10 with a reserve. If anyone gets these here, let us know how you like them.
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michigannick
Well-Known Member
drool
:jawdrop:
:jawdrop:
c-atle-79bay
Super Member
Hum, Idaho is not far from Seattle.
c-atle-79bay
Super Member
Also a set for sale in Florida for a nice price.
luvmusik
HOORAY !...ELECTRICITY !
Another different model up for sale today on ebay (not affiliated). Older early model, add title is "RARE Vintage IMF Transmission Line Studio Monitors Speakers Split 1OWNER England". Area is Albuquerque, New Mexico. Appears to be a Studio I model (the Studio) possibly, rather than the model add is stating as a Studio Monitor, which is different.
Uhmmm, right in my neighborhood! But I do believe I have more speakers than space right now!!! :sigh:
luvmusik
HOORAY !...ELECTRICITY !
Can't believe these didn't sell nor meet reserve with 9 bidders. Bids only went to 669, I believe these are worth 900 to 1200 for pickup, unless shipping (expensive) needs to be figured in. Guy relisted them; now at a steal for 750, IMO. I paid more for mine really beatup and all drivers needed replacement other than 2 good mids, worst financial decision I ever made in audio over 46 years in it. I did acquire all but 2 of the needed drivers (6) so far, but just don't have time to rework them; and still need to buy 2 Coles supertweeters. All said, I laid too much into my set so far & time is money also. When mine someday are done it will be close to 1200 finished, with scratched cabinets, but I have stands which also need repainting. That 1200 did include buying set, gas, suv rental and 4 OEM drivers bought to replace bad drivers (still need to buy 2 Coles from UK shipping to USA). The set in add is mint, near new-condition; I think it is a sensational deal. I should've waited for a deal like that; after I got mine, 6 sets sold near me in far better shape (3 were mint) for less or the same amount (700) I had paid, within 2 years.
I did get 1 xtra woofer (spare) and a wider-tolerance recap set with mine. If I put all the time into a recap someday (doubtful), I would then only do it with the tighter-tolerance recap set I would need to buy, to get closer to original spec (making the time involved more worthwhile to best completion), and at that point my total outlay would be over 1300; keeping poorer recap set just for emergency spares; still needing much time for any refinishing of veneer scratches and steel stands repainting to be involved. That 1300 does figure in compensation for the 1 xtra woofer & wide-tolerance cap set. I bought them thinking I'd never see a set come my way, and it is the only piece of gear that needs work I own other than some replacement mids in IMF SC II... I also have now to put in, as a project on back-burner (interesting Brit speakers & IMF often require work) in future with time. Don't have time to work on fixer-uppers, so I only buy all my other gear mint; learning lesson for me, will never buy a DIY again, but that's just me -very little time here even for listening, which is top priority over fixing. Overall my outlay dollars to completion is near double of the set in add, which is ready to plug & play -what a blessing. Hope an AK'er gets 'em.
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Sheltie, are you in San Diego now, or still in St. Louis as your location states? If you ever need any other IMF's, let me know, I'm in Northern OC, only 90 minutes away.
michigannick
Well-Known Member
Someone needs to put a call into all the Idaho AKers thats a nice price but a long haul for most everyone
Mart Mccall
Active Member
I just joined the IMF owners club. These pair of TLS Mk1 arrived this morning.
Sorry about the light in the photo, it is unusually sunny here today:
I've never heard any IMF before. First impressions: refined, polite, clean in the mids, impressive bass response. Effortless, but deep and tuneful too.
Sorry about the light in the photo, it is unusually sunny here today:
I've never heard any IMF before. First impressions: refined, polite, clean in the mids, impressive bass response. Effortless, but deep and tuneful too.
Welcome Mart Congrats,look pretty clean,very complete speakers full range
