TDL Electronics Owners Thread

There is something about the effortless presentation of the bass in that speaker that is aw inspiriring. At first I took them for weak or a bit shy in bass, but once you get that box bass boom out of your head it's so much better. These speakers completly changed the way I hear bass.
 
Well I guess my budget won't reach those anymore, so I'll have to stick to my IMF RSPM Mk IV's, they're rare enough in Australia, but the TDL's are even rarer.
 
I've come to realize that I so respect the research KEF did to produce some of the best speakers from the 70's, 80's and so on. So many companies used KEF speakers back in the day in their own designs or DIY's. My hat off to you KEF!

As IMF_Pioneer has stated, TDL are rare in Australia. Would like to hear a set one-day.
 
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I've come to realize that I so respect the research KEF did to produce some of the best speakers from the 70's, 80's and so on. So many companies used KEF speakers back in the day in their own designs or DIY's. My hat off to you KEF!

As IMF_Pioneer has stated, TDL is rare in Australia. Would like to hear a set one-day.

KEF really is an amazing company. Not only were they pioneers in sound reproduction back in the day, they are now. They've managed to adapt their business and continue to develop exciting new technologies that are completely relevant and worthwhile. The IMF/TDL sound was no doubt shaped by their engineering choices since the transmission line was designed around the famous KEF B139.

I too would love to hear those TDL reference models with the dual woofers. It's a shame they are rare. But I've always believed that if you are meant to have them, they will find a way to you!
 
Hello all -

(Hi Geoff, hope you are well!)

First post here - very happy to find you guys!

I've just picked up a pair of TDL Studio 4s - Very excited! Cosmetically they're in great shape and the drivers all appear to be in pretty good condition (there's even a spare mid and bass units) - but they're very bass light (I'm guessing the bass drivers on both sides are down around 6 dB)- I'm thinking that as the drivers themselves all appear to be working OK and moving freely, this may be something to do with the crossover. Might need new caps?

There was an annoying rattle coming from the back of one of them which I tracked down to a loose nut on the back of (inside the speaker) one of the terminals - However - as I was removing the terminal panel, the internal wiring broke off of a couple of the terminals - I have to say, the quality of the soldering job was absolutely dire, which made me start to wonder what else was going on "under the hood" - Also, it surprised me to find that the wiring from the terminals to the crossover (all the wiring in fact) is solid/single strand wire - is this normal on a TDL of this era? My Studio 0.75Ms certainly aren't like this
I took the bass driver out to have a look at the crossover (again, the very poorly soldered single strand cable broke straight off the driver as I was carefully moving it away from its' orifice.)
Anyway - the crossover is very home-made looking - a piece of MDF with components soldered to what look like nails. Apart from the inductors hanging off by their wiring, does this look normal to you guys? I've not a huge amount of experience with vintage hifi, but I was expecting something a little more "manufactured" looking - again, the crossovers on my Studio 0.75Ms don't look like this.

I've had a look online and can only find one image with a wiring diagram for a Studio 4 crossover... (although it does say TDL Electronics Monitor Studio 4? which isn't a model designation I had come across, I am assuming the implication is that this crossover set up is applicable to the Studio 4 and maybe the 3-way version of the Monitor/Monitor Compact that was sold in Europe?)

http://www.cma4ch.org/chemo/image/hifi/TDL-Monitor-Studio4.png

The layout and values differ substantially to what I'm looking at here....
TDL Studio 4 xover.JPG


By any chance, does anyone have a wiring diagram for the TDL Studio 4 crossover? Or any idea where I might start to look? I've googled it to death and I'm getting no-where. If I'm going to rebuild the crossovers from scratch I'd like to be sure I've got the right components/values.

many thanks,

Dan
 
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I think you'll find that TDL was a tad more professional than what you have sadly fallen across. What's in the photo is what many Project Magazine DIYers did back in the 1970's in their garden sheds.

Solid copper strand wiring was totally out of usage by the time TDL took over from IMF in the 1980's.

If you have no luck online please contact Jerry Bloomfield at "Falcon Acoustics" in the UK and I'm sure he'll be able to help you out.
 
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I think you'll find that TDL was a tad more professional than what you have sadly fallen across. What's in the photo is what many Project Magazine DIYers did back in the 1970's in their garden sheds.

Solid copper strand wiring was totally out by the time TDL took over from IMF.

If you have no luck online please contact Jerry Bloomfield at "Falcon Acoustics" in the UK and I'm sure he'll be able to help you out.
Thank you IMF_Pioneer - I'll try messaging him.
 
Hi!
I build my TDLs in the early 80's and I have been more than satisfied. The tweeters have not been treated well over the years by the younger members of my family, but they sound much better than they look! Also the midrange surrounds are starting to crack up so I am considering buying replacements.
The TDL Monitor has a fabulous bass and I find the overall sound balanced and smooth.

Here's a link to my TDLs

Lately I started a 3-way TL project using 12" bass, but the first listening test was not promising! Guess I'll stick to the TDLs!
 

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Please let us know how you go with Falcon.

Cheers,
IP.
Jerry at Falcon was as helpful as he possibly could be - and responded to my email within minutes, even though it was late last night - he sent me the same diagram I had included in my original post, saying it had been sent to them at some stage, but he couldn't guarantee the accuracy. So in an ideal world I'd still like to verify this info somehow, as the origin of this crossover diagram is from an old blog from someone in Italy who was renovating/upgrading a pair of Studio 4s and it is not clear to me whether this is the original crossover design, or his own design. Most of the links in the blog are dead and there's no obvious way to contact the author.
 
Hi!
I build my TDLs in the early 80's and I have been more than satisfied. The tweeters have not been treated well over the years by the younger members of my family, but they sound much better than they look! Also the midrange surrounds are starting to crack up so I am considering buying replacements.
The TDL Monitor has a fabulous bass and I find the overall sound balanced and smooth.

Here's a link to my TDLs

Lately I started a 3-way TL project using 12" bass, but the first listening test was not promising! Guess I'll stick to the TDLs!
Hi Shiva12 - I have a vague recollection that the TDL "Monitor Compact" was sold in Europe in kit form - is this how you built yours?
& thanks for the link to your TDLs - the 4-way Monitor is a similar enough design, it might help me confirm aspects of the crossover design in the 3-way Studio 4 if I can't get definitive information. The values of the inductors (and a couple of the capacitors) are missing from the crossover design in your link - I don't suppose you happen to know these values?
 
Hi Shiva12 - I have a vague recollection that the TDL "Monitor Compact" was sold in Europe in kit form - is this how you built yours?
& thanks for the link to your TDLs - the 4-way Monitor is a similar enough design, it might help me confirm aspects of the crossover design in the 3-way Studio 4 if I can't get definitive information. The values of the inductors (and a couple of the capacitors) are missing from the crossover design in your link - I don't suppose you happen to know these values?

Hi SubsonicDan

I bought the TDL Monitor in Denmark in kit form, with box drawings similar to the ready-made version as shown in my project link.
Sorry about the inductor values. They were not marked.
 
Hi Shiva12 - I have a vague recollection that the TDL "Monitor Compact" was sold in Europe in kit form - is this how you built yours?
& thanks for the link to your TDLs - the 4-way Monitor is a similar enough design, it might help me confirm aspects of the crossover design in the 3-way Studio 4 if I can't get definitive information. The values of the inductors (and a couple of the capacitors) are missing from the crossover design in your link - I don't suppose you happen to know these values?

You mention Studio 4 - is this what you are looking for?
http://www.cma4ch.org/chemo/attivita/TDLstudio4.html
 

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You mention Studio 4 - is this what you are looking for?
http://www.cma4ch.org/chemo/attivita/TDLstudio4.html
Thanks again Shiva12 - that's the same link/crossover design I turned up before - I don't want to look a gift horse in the mouth! but it's not completely clear whether this is the original crossover design or his own design - you understand I want to be as sure as I can be if I'm going to undertake building new crossovers from scratch.
 
Hi SsDan,

Thank you very much for your feedback experience with Falcon. Jerry is a very accommodating gentleman and gives his very best to any Hi Fi enthusiast.
I guess you are not in a better spot at the moment. It's hard to know whether" it's just a jump to the left ?" as sung from a well known movie (Rocky Horror Picture Show) or one to the right ?. I hate being in this predicament.

I must admit if Jerry doesn't know 100% then you are in a spot of bother.

again let us know how you go.

Cheers.
 
Hi IMF_P,

Well, I'm not completely out of options yet. I've been emailing with Axel at A.O.S. - who used to distribute TDL products in kit form across Europe - including the Monitor and Monitor Compact.

It's not exactly straightforward though - the Monitor Compact is not as similar to the Studio 4 as I had assumed; Axel says he started to develop the product line he was selling independently of TDL around this time, starting with changing the mid driver and crossover in the Monitor Compact.

Still, he's a jolly helpful chap and said he would have a dig in his archives and see what he could find for me. Fingers crossed.

Failing that...I'll either have to repair what i have and put up with them like this for a while,

or...

1) I have a pair of Quad 405s, so I could see what I get from bi-amping the Studio 4s. It would certainly help to be able to attenuate the mid/hf section compared to the bass.

2) I have been toying with the idea of bypassing the crossover all-together and running them 3-way active. I'm thinking I'd use the Quad 405s for bass and mid, and i'll probably have to return to this forum for advice on what would be a suitable (& not too expensive!) amp to drive the HF, and also some recommendations & advice on running active crossovers.

eg Would it be best/normal to still employ some kind of passive high pass filter to protect the hf and mid drivers in this scenario? (I'm thinking that many of the amps I have owned produce quite a thump on powering up/down, which I would imagine an hf driver might not survive)

cheers,

D
 
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So - I retrieved my other Quad, repaired the crappy wiring and glued the inductors back onto the "circuit board" and I'm now running the Studio 4s bi-amped. What a difference! They've gone from a 3 to an 8.5 once I got the right balance between the bass units and the mid/highs. Very happy. Oh, the bass!

(I'm sure my neighbours are enjoying them too.)

So, as (definitely) temporary and easy fixes go, quite successful - even with the current crossovers, they're reasonably well balanced - maybe a bit peaky around 1k, and a touch subdued from 2k-4k, but not too far off, and the way the bass joins to the mids is pretty seamless. Result!

(I'd still be happier to find the correct crossover design though, if anyone happens to have that info...)

Thanks for your help & advice guys.
 
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