TDL Electronics Owners Thread

Also if any one wants to sell a pair of reference standard M version i have cash waiting I have owned two pairs over the years but sold years ago and now would like another pair
 
I've managed to pop out my domes, they are in OK condition, but have figured out why one of the woofers is not working or at least the likely cause, corrosion and oxidation of the terminals and leads. And unfortunately the magnets for the dome tweeters say they are 16 ohm the ones on ebay are 4 and 8 ohm, so have to live with it. Also one cracked dome, such is life. Now time to clean the oxidation off.

Ok perhaps not the corrosion, but the leads are greenish in color, volt meter was dead and too late to change the battery.
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Disintegration of the foam port inserts with TDL RTL2s seem to be a common problem (& probably the same with others in the range). Does anybody know the type of foam that was used, & ideally a source?

Strangely the inserts have gone completely on one speaker - not the other. I don't want to touch the other one just in case it takes offense & breaks down to crumb. Assume it spent less time in the sun :-(

I've generated a template in CorelDraw & need some 10mm thick sheet to (hopefully) cut out replacements.
 

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Found a source of 10mm thick reticulated foam which is sold for facing speakers - so it's acoustically transparent. £5 for a 320mm x 220mm piece.

Used the template to cut out a relatively "square" piece & then cut the radius corners to suit. I'm happy with the results. Not perfect - better if the template was a piece of plywood - but at foot level, they look OK cosmetically.

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Found a source of 10mm thick reticulated foam which is sold for facing speakers - so it's acoustically transparent. £5 for a 320mm x 220mm piece.

Used the template to cut out a relatively "square" piece & then cut the radius corners to suit. I'm happy with the results. Not perfect - better if the template was a piece of plywood - but at foot level, they look OK cosmetically.

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Hi, I have a same pair of RTL2s with the same rotten foam issue. I'd like to know if it affects the sound or not with or without the filler?

And, it is funny that my RTL2s ports are rectangular in shape, different from what's shown on your photo......
TDL%20RTL2%20bottom.jpg
 
Hi all,

I've done a bit of experimenting on my RSPM Mk IV factory "Improveds", in other words "P" prefixed serial numbers that had the Reticulated foam inserts installed in the ports from the factory and I replaced them due to the dreaded foam rot. Honestly I feel that the foam chokes the enclosures and they sound better without. I sourced some 20 grade which is the coarsest grade that's made and all I can say is they improve the looks but not the sound.
 
Strangely, only one of the foam inserts broke down & I didn't want to disturb the (glued-in) other one. So, I've never been able to listen to the speakers with/without inserts. I've not been able to detect any difference to the sound since replacing the second insert.

The foam I used was very open, like the foam that it replaced, & was described as specifically for speakers grills. Not sure what "20 grade" is in the previous post. Assume it must be density.

BTW, the speaker grills on yours look to be almost full height (except the ports) whereas mine are the upper 60% (approx). The plinths are different as well.
 
The 20 is most certainly the density grading. 20 is the coarsest you can get in reticulated foam. It is used for speaker facings and also air conditioner filter inserts.

It goes up in numbers of ten, so there is 20 (being the most open), 30, 40 and 50 (being the densest) if my memory serves me correctly.
 
Hi, I have a same pair of RTL2s with the same rotten foam issue. I'd like to know if it affects the sound or not with or without the filler?

And, it is funny that my RTL2s ports are rectangular in shape, different from what's shown on your photo......
TDL%20RTL2%20bottom.jpg
The TDL Studio RTL-2 is an aperiodic cabinet design where the foam at the port is a acoustic resistive element very important to the loading, thus the bass response of the system. It is made of "medium" density open cell foam. Most speaker grill foam are too open. JimPA may have some suggestion on the source of this foam.

Are the mid woofer and tweeter drivers new? Did you modify the crossover to accommodate them?
 
I do not own a TDL speaker and hope that my post can be accepted.

I was always a big fan of the TDL Studio 3 monitor, which was impossible to find in the US and shipping from UK is prohibitively expensive. A few years ago, I ran into some “Wharfedale M-138 Transmission Line Monitor” from Wharfedale in China (Pic 1). I bought them out of curiosity and found that they were the TDL knock-offs. They have the same aperiodic cabinet design (not Transmission Line) as the TDL (Pic 2) and a 2nd order crossover. The cabinet was very well built, but the drivers were very poor quality. I started a mod project.
wharfedale138_peerless-seas.JPG Wharfedale138cabinet.jpg

(1) I replaced the drivers with a pair of Peerless 850460 woofers and a Seas 22TAF/G ¾” Aluminuim/magnesium dome. (I also tried Seas 22TFF soft dome which is interchangeable as far as the crossover is concerned.)

(2) I modified the cabinet by lining it with 3M 08840 Sound Deadening Pads and replaced the polyester wadding with long fiber wool.

(3) I modified the crossover to 3rd order and added a zobel network for the woofers. (Pic 3) I was able to keep the circuit board and bi-amp input panel. (Pic 4)
wharfedale138_peerless-seas_xover.JPG IMG_2391.JPG

Crossover mod was supported by Jeff Bayby’s PCD software which worked beautifully. The simulation result is shown in Pic 5. I kept the woofer bump to get a bass -6dB cut-off at 35 Hz. It worked exactly as expected. After I fine tuned the driver balance by ears, I made in-site measurement using Ivo Mateljan’s ARTA software. The dip at 450 Hz and the treble drop-off are room effect because I did not make the effort to measure outdoor. (Pic 6)
wharfedale138_peerless-seas_simulation.JPG wharfedale138_peerless-seas_measured.JPG

The woofer section with 2 drivers in parallel is about 5 ohms. The impedance rises higher in the single tweeter section. Below is the PCD7 curve. I did not make impedance measurement.
impedance_wharfedale-Seas_p-2.gif
 
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