SubsonicDan
Member
erm.... I'm not sure you guys are referring to the same picture. The MDF x-over (from my speakers) doesn't have any TDL markings. The PCB one from Chops54 is obviously the correct manufactured part.
TDL Studio 4
- Thread starter Chops54
- Start date
JensenHealey
pfm Member
Yup - I cannot believe the MDF jobby is anything to do with TDL. I wonder if the whole speaker got rebuilt somewhere along the line, by an amateur
SubsonicDan
Member
Or a prototype, or parts bin special after TDL went under? ... I'd love to know, but unfortunately the original owner is no longer with us to ask.
Certainly everything to do with the electrical side is non-standard. All of the wiring is solid core/single strand copper.
Certainly everything to do with the electrical side is non-standard. All of the wiring is solid core/single strand copper.
awkwardbydesign
Officially Awesome
I can see the picture from SubsonicDan now. That's where the confusion was. But Chops54 is the OP in this thread, BTW.
davidsrsb
pfm Member
I believe that the Studio 4 was fairly early in TDLs history, after the transition from the IMF like monsters. The later models all used a pair of conventional circular woofers in MTM
SubsonicDan
Member
I think you're referring to the RTL 3 - Which appears to be the most widely sold late TDL Electronics design (probably accounts for half of the proper, pre - Richer-Sounds TDLs you see on fleabay), but this was by no means the only model they were selling at this stage. The RTL range were at a lower price point, & were not a transmission line design, despite the name, and ran in parallel with the Monitor and Studio ranges. Some had dual bass drivers, as you described (RTL 3 and 4, the later T-Line 3) Some didn't. (RTL 1 & 2, and then the T-Line 2 had a single LF driver below the HF)
The Studio 3 also had this arrangement (2 LF drivers above and below the HF) but the Studio 1 & 2 (2 drivers, LF above HF) and 4 (3-way featured in this thread) did not. The 4-way Monitor, Studio 2 and 3 were eventually dropped. The Studio 1 went though quite a few revisions, eventually becoming the 1m; the very small floor standing transmission line Studio 0.5 was briefly available - and then eventually the Studio 0.75m, 1m, 4 and the RSTLm continued in parallel with the RTL and then the later T-Line range until the rights were sold to Richer sounds, who scrapped the whole range and put the TDL badge (dropping the "Electronics" part of the moniker) onto some budget nonsense of their own design. (Studio 5 & 10, Saturn, Nucleus etc)
In addition, there was a parallel range of TDL Monitors distributed in Europe by A.O.S.- mostly in kit form. Some were a 4 way, like the Monitor here, and some were a three way - similar to the Studio 4, but with the mid above the HF (known as the monitor compact) The distributer's product line started to diverge from the UK line when the Studio 4 was released, and they eventually started selling their own transmission line monitors with ATC & Scanspeak drivers.
Confusingly, the name "Monitor Compact" had been used by TDL a few years earlier in the UK for a bookshelf sized speaker.
SubsonicDan
Member
Sorry chaps, I completely went off on one there...
SubsonicDan
Member
By the way, thanks again Si - those pictures of the x-over you posted yesterday were dead helpful, they exactly match some info offered on another forum - so I should now be able to get a pair of circuit boards made up...
Slowly piecing together the info I need, but I'm still missing the values of some of the components (all of the inductors for example!)
Slowly piecing together the info I need, but I'm still missing the values of some of the components (all of the inductors for example!)
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Chops54
pfm Member
You're welcome Dan. I'm happy to remove a crossover for further investigation if it might help.
I went to see my friend today and came away with this brochure. What you have is not a pair of Studio 4s but a pair of Studio Monitor M's. From the info in the brochure I can only assume that they are a improved version of the Studio 4. Those midrange units in the Monitor M have impressive cast baskets instead pressed steel and have ferrofluid cooling too. Id love to hear what a correct pair sound like.
Scans of the brochure. These show a bit of the crossover and other useful info.
I went to see my friend today and came away with this brochure. What you have is not a pair of Studio 4s but a pair of Studio Monitor M's. From the info in the brochure I can only assume that they are a improved version of the Studio 4. Those midrange units in the Monitor M have impressive cast baskets instead pressed steel and have ferrofluid cooling too. Id love to hear what a correct pair sound like.
Scans of the brochure. These show a bit of the crossover and other useful info.
JensenHealey
pfm Member
You could probably make a good version without a printed circuit board. Point to point wiring will do just fine for one-off.
You need to double, triple check that your speakers have the correct drivers - I am wondering whether a change of drivers (originals blown up?) has prompted the mess you have uncovered.
You need to double, triple check that your speakers have the correct drivers - I am wondering whether a change of drivers (originals blown up?) has prompted the mess you have uncovered.
Chops54
pfm Member
According to that TDL brochure the drivers are correct. I've just had a thought ( dangerous I know 
) but I've just remembered that Lockwoods bought all the TDL parts when they wrapped so that would be a good place to start. You never know, they might just have some crossovers in a dark corner somewhere.
) but I've just remembered that Lockwoods bought all the TDL parts when they wrapped so that would be a good place to start. You never know, they might just have some crossovers in a dark corner somewhere.SubsonicDan
Member
That's fascinating Si - I'd never heard of the Studio Monitor M. It wasn't clear looking at the front of the midrange cones what material they are made from, but from the rear the blue-ish black colour does look like anodised metal. They don't appear to have the pronounced phase plug that's shown in those documents, but they do have cast baskets.
So it seems like hunting for info on the crossover of the Studio 4 and/or Monitor might have been a bit of a wild goose chase, as the crossover point is different (2k on the Monitor M vs 3.5k on the Monitor and Studio 4)
@JensenHealy - Yes, it could offer an explanation, it had crossed my mind - didn't want to look a gift horse in the mouth, but I was a bit suspicious that they were offered with a complete set of spare drivers, (although the spare hf is a standard Audax rather than the original Elac.) But why replace all the wiring with solid/single strand copper? And why go to the trouble of making new crossovers and then get your cat to do the soldering?
SubsonicDan
Member
Ah - good call!According to that TDL brochure the drivers are correct. I've just had a thought ( dangerous I know
I'd forgotten about them - I did try to contact them once before when I was looking for parts for my 0.75Ms - I'll give them a call tomorrow.
SubsonicDan
Member
If I manage to speak to anyone who knows about the TDL spares, I will ask, of course. I assume you just need a diaphragm rather than the whole driver? It might be best to confirm the model number on the driver - 25DT something.
SubsonicDan
Member
Hmm. I wish you hadn't gone there. (I don't mean Malaysia)
Replacing the ferrofluid on an HF driver is painstaking enough, but at least the components are all designed to come apart fairly easily. The same can not be said of these mid drivers.
Replacing the ferrofluid on an HF driver is painstaking enough, but at least the components are all designed to come apart fairly easily. The same can not be said of these mid drivers.