Early IMF

[behind the rock]

I mntioned before about my Transmission Electronics TL speakers being one of the earliest incarnations of these famous loudspeakers marque. I discovered by accident today when I removed the x-overs from the speakers and uncovered on the pcb that IMF TRANSMISSION LINE MONITOR LOUDSPEAKER is etched on the pcb underside.  Apologies that the photos are not crystal clear. The speakers are mounted on castors for easy movement alledgedly so they could be moved about in a studio, but more probably for anyone to save back ache! It raises an interesting question about the involvement of Fried and his initial as part of the company name.  I'm almost certain he was not involved at this earliest stages.  So that means the company name was there even back then when the speakers were built in an electrical store although the label states otherwise. Don't know what MDKT signifies. Does anyone else know Fried's first involvment?







Andy

[physeter]

Can't help,  but I'm on the same boat as you. I also have  a pair of early IMF transmission line and mine are labelled as MDW

[behind the rock]

Does your speakers have three or four drive units?  Can you identify them?

Andy

[physeter]

Hi Andy

Four drive units, they look like the later professional studio monitor and the tls 80



Javier

[behind the rock]

I think thats a Coles super tweeter but I'm not sure about the oblong tweeter.  Peerless maybe?  I'm noticing that the vent at the bottom doesn't appear to be stuffed with wool at that point, unlike mine.  They probably experimented with different line stuffing arrangements to improve the bass end. 

Andy

[physeter]

It just have a green foam inside the bottom vent. Definitely not wool. Sincerely I don't have much info about the speakers; all I can say is that they sound superb and the only part I can easy recognise is the B110.

[Phil Y]

Tweeter looks like a Peerless, Radford also used their tweeters in that era I think.
This is a peerless K010DT that I have a pair of. Looks very similar.



Phil.

[ZM1080]

The bass unit is a KEF B139, and the round tweeter looks like a Coles 4001.

[physeter]

Thanks

Here some pictures of the drive units ( sorry for the crappy quality )

[behind the rock]

The bass unit we have is the KEF B139 SP6171 later superseded by the B139 SP1044 with integrated cast chassis.  Your Coles supertweeter is still available from Wilmslow Audio. Also your KEF B110 midrange has a doped cone to minimise a resonace particular to that unit. 

Andy

[physeter]

The bass unit we have is the KEF B139 SP6171 later superseded by the B139 SP1044 with integrated cast chassis.  Your Coles supertweeter is still available from Wilmslow Audio. Also your KEF B110 midrange has a doped cone to minimise a resonace particular to that unit. 

Andy

Thanks Andy!

[Andrew.R]

Your lucky to have these IMF's, always fancied trying a pair.

[behind the rock]

They're a bugger to transport, mine came on a Euro pallet!  Look out for the Lentek transmissioneline speakers, they were my first speaker.    Marginally more room friendly.  Still sound good as well. Different tweeters, T27 and I forrget the supertweeter.  In my opinion the cabinet is better braced. 

Andy

[Andrew.R]

Andy,

Got your PM, nice surprise! Well you talk about room friendly, I have a pair of 350 litre Tannoy 15" Monitor Golds sitting in front of me  now that's NOT room friendly  .  I've never heard a pair of IMF's so I'm always on the lookout for a pair and I'm a sucker for 70's speakers!

Thanks

A

[ZM1080]

On closer inspection, that white tweeter is not a Coles unit. May be a very early KEF T27?