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Lentek monitor speakers?

absolon

absolon

Super Member
Ran across a pair of unusual speakers today and I'm wondering if anyone knows anything about them. Sorry, no picture.

They are Lentek Monitors, made in England and about 48" tall by 15" square. The cabinets were walnut veneered with inset removeable fabric grilles. The drivers were a small tweeter, roughly 4 1/2" mid and what looks like a passive radiator about 5" x 10", all located on the upper third of the cabinet. There is a small rectangular port on the front about 2" x 5" located near the bottom and grey stuffing is apparent..

The store manager commented they were exceptional speakers though I didn't get a chance to hear them. A Google search only turned up some information about a highly rated amplifier built by Lentek but nothing on speakers. Price is $180 Cdn the pair.

This seems to me to be an odd configuration. Does anyone know anything about them or how they might work?
 
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Lenteks were very highly regarded transmission lines in the 70's. I'd scamper right back down there and buy them. While the IMFs might have been more higly refined, with all the multiple drivers and complex crossover they were also either tremendously power hungry or not very dynamic. But if you've never listened to a transmission line, the bass from even small drivers is startling -- not just for amount but for clarity and liveness. Go buy them now!
 
The "passive radiator", if oval, sounds like a KEF "racetrack" woofer. If the drivers are all KEF, they could be magnificent. The description sounds like they might be TL's, like the IMF's which ARE magnificent.

See also www.t-linespeakers.org for more on TL's and KEF drivers (as a matter of fact).
 
Nat, you talked me into it.

Thanks all for the information. I went back this morning and picked them up and am giving them a test run as I type.

Clear, fast, detailed, very open sounding and well worth the coin. Bass is there but not dominating. Seem to handle 100W with no difficulty.

They are four way and the drivers (see attachment) bear a strong resemblance to the KEF drivers shown at the TL link. I'll know more once I open them up. Drivers are in excellent condition and appear to have butyl surrounds. Boxes are not bad but need refinishing, a project I'll undertake while I figure out how to get these in the house. They have low WAF due to the size. They are big and heavy enough to require a hand truck to move.

Found a listing on Orion for Monitor 4s, 78-82 and about $1200.

I'm very pleased with them, thanks for the good advice :thmbsp:

Edit: double checked against the KEF pictures at the TL link and I'd say with 95% certainty that at least the woofer and the mid are KEF.
 
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After an hour of Tchaikovsky's Violin Concerto in D Major and Serenade for Strings, all I can say is:


WOW!
 
I have IMF TLS50's

and your Lenteks look almost identical to IMF TLS80's. :yes: I'll never part with my TLS50's! :thmbsp:
 
Fascinating! a Lot of math musta gone into that design. It takes a brave man to design a TL with a passive radiator, there are so many variables to consider.

Just wish I could hear them. Chances of finding those here is ZERO :cry:

A great deal of VERY good speakers used those drivers :thmbsp: If you open up, will you post pics of the x-overs? I would love to know how they implemented the design

Best regards

gerrit
 
I'll think you'll find the big flat fella bottom left isn't a passive radiator - it's a KEF B139 bass driver.

The top left driver is a KEF B110 and the top right is a KEF T27. not sure what the tweeter bottom right is, but it's likely to be either another KEF or a Coles' unit.

These plus transmission lines equal all the right ingredients for a cracking loudspeaker!! :thmbsp:
 
Beo, you are indeed 100% correct Sir. I just assumed it to be passive 'cause of it's unconventional design (come on admit it, it looks like a passive?? don't it)

We all know assumption is the mother of all screw-ups so I apologise BUT this only makes the speaker even more fascinating... I gotta hear this... Anybody for a holiday in SA?? no...mebe 2010 World cup soccer.... Anybody?? :naughty:
 
Bolly, I understand why you won't part with your IMFs. These are a little bigger than the TLS80s and the organization is a little different but I imagine they are close in sound due to shared components and design. I'm going to have to build a new stereo cabinet as the only possible way to integrate them into our rather compact house, but after that, they're not leaving either.

Gerrit, I'm as curious as you are but due to work deadlines, I won't be able to get at them for a while. I will post pictures when I do. It looks possible that the whole front baffle can be unscrewed and removed, but then again, the screws might have been intended to hold the parts together til the glue set.

Thanks for all the info on the components and the comments :D :D :D . These speakers are remarkable when driven by my Sony's, absolutely invisble. I'll update as I make progress.
 
I'm not positive about this, but my memory is that the line in lenteks was formed by two panels that made a cross internally, so that all the walls were more braced than in IMFs where the line was sort of layered.
I'm inclined to think that it might not be a very good idea to open the cabinet up (even if its possible). You probably can get at the crossover through the woofer hole, if you need to, but if they are good as they are, why fix what ain't broke?
 
Have found a little more info from a gentleman named Colin Royle who has actually heard a pair of the speakers and who appears to be associated with this site: http://www.hifiloudspeakers.info/index.html .

These speakers come from Huntingdon in England near both Quad's and Meridian's factories. The supertweeter, bottom right in the photo, is a Celestion HF2000 which was also used in an the early version of the TLS80s. He thinks the crossovers are similar to ones used in the Webb TL and Cambridge 50.

Nat, I'm very curious about the baffle structure but I won't take them apart unless I am absolutely certain I can easily get them back to exactly the same condition they started in. I've burned my fingers often enough to know my limitations.
 
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Just had a look at the site, and nice to see my very own pride and joy mentioned somewhere at last - Ferrograph S1's!! :thmbsp:

They're coming out of storage and into my new listening room soon, so i'll try to post some pics.
 
Found an old (mid 70s) HiFi News Annual with a short review of the Lentek Monitor. Apparently there is a horizontal divider that separates the midrange and tweeter and crossover from the transmission line, which is formed by two panels forming a cross that are fitted at an angle to the cabinet to spread resonances.
Typically transmission lines aren't really all that investigatible -- they need to be rigid and once together can't be taken apart. Wish it were otherwise, since I have a pair made from the active elements of a KEF 104ab kit, which appears to be improperly stuffed (down about 6db from about 120 down to 30 hz and then up about 12 db at 20 hz(!)). Some of that is obviously room acoustics, but only to expansion chamber seems to be stuffed. The rest of the line appears unstuffed. While is is interesting that an 8 inch woofer can produce very strong 20 hz tones, it would be more interesting to me to have flattish response down to 30 or 40 hz. I can think of ways to finesse stuffing through the line, but it sure as heck would be easier to take it apart, but no....
Incidentally, the review suggested the lenteks sounded best away from corners and out about two feet from the wall, with a touch of bass boost, though classical sounded properly balance without the boost.
 
Appreciate the info Nat. I had difficulty picturing what you were describing but Colin supplied a link illustrating the configuration that clears it up:

http://www.hifiloudspeakers.info/An...Gallery/Bailey/BaileyWWW1972/pages/ww72b2.htm

There are screws in the appropriate locations on the front baffle to catch the edge of the vertical line baffle that intersects the front baffle so I am fairly certain the configuration matches. Based on the info, there is not a chance I'm going to try removing it.

Now for the good news. Based on some judicious timing, a well thought out approach, the expenditure of my entire reserve of domestic credit and a day spent washing floors, the speakers have moved into the living room where they will henceforth reside. This is acoustically far better than building them into the stereo cabinet and will allow placement as you have suggested when I have a serious listening session. I've had an enjoyable day listening to a variety of music and like them better and better. To my ear they are very well balanced, which I suppose is an indication of a very flat response and the soundstage seems to reach over and around me. The detail is remarkable; I'm hearing new things in every piece I've listened to.

It's radical surgery, but have you considered cutting an access panel to restuff your speakers? With careful work, a rabbetting bit on a router and some epoxy adhesive, it is quite possible to return the panel you open up to monolithic condition. Depending on where you went in, it would likely require reveneering to hide the repair, but it could solve the problem.
 
Haven't had time to dig in to these yet but have had many hours of listening to them.

Thanks Nat. Some of the best advice I've had in years.
 
Good score, and only $180 Canadian.
I am sure they sound sweet.
my main system I have a Pair of TDL Studio 2 Transmission lines and they are very nice indeed, very laidback sound. But with alot of slam......... bit like a velvet sledgehammer :)

My other speakers that are based on the transmission line is a pair of dynaco A-25, and a Pair of B&W dm-2...

I will have to keep an eye open down here and see if I can find a Pair of Lentek Monitors...
Enjoy the Music :yes:

Cheers!
9090
 
I'm going on memory here.

And I have to admit I didn't look at the reveiw link given earlier.IIRC Lentek was a company which also made amplifiers which were designed by the man who designed the amps for the (later) amplifier company Audiolab(later bought out by Tag-Mclaren).I think his name was Phillip Swift.Don't know whether he designed the speakers or not. :no:
Here's a link to an Audiolab preamp.

http://cgi.ebay.com.au/Audiolab-800...99874861QQcategoryZ109836QQrdZ1QQcmdZViewItem
 
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