• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Tangent TM-3 Crossover

exhilaration157

exhilaration157

Active Member
Well I'm on a Christmas break crusade to fix everything.

So yet another crossover thread.

My Dad has a pair of Tangent TM3 bookshelf speakers purchased in 1977. They are in great shape, but they could definately benifit from replacing the capacitors. I just replaced the capacitors in my Advance V-IIs (with 10 uF solens), which had a much simpler crossover. So, I have a few questions on what capacitors to buy: polypropylene vs. electrolytic.

One of my main concerns is the 50uF cap. That would be a rather large polypropylene cap. Anybody try the Dayton metalized PP? Also, replacing the inductors with higher quality inductors should help the sound quality but the inductors don't degrade do they?

I've attached a crossover schematic. Here is a website with the pictures.

TM3 - http://www.thunders.ca/tangent/tm3.php
TM1 - http://www.thunders.ca/tangent/tm1.php (better pictures, same but larger ported cabinet).
 

Attachments

  • Tm3 XO.jpg
    Tm3 XO.jpg
    27.5 KB · Views: 406
Register to hide this ad
For the record, I'm not familiar with these particular speakers...

The 50uF cap is in the woofer circuit. It's unlikely that using a poly cap will net you anything, sonically. I'd stick with an electrolytic. Besides, it's cheaper.

I'd also leave the inductors alone. They tend to be pretty bulletproof. Better quality inductors will likely have a lower DCR which could alter the speakers' sonics. You can compensate with resistors, but why go to all that trouble?
 
I took out the crossover. It has strange color coded caps on it. I'm pretty sure about their values from the schematic. I'm pretty sure the Christmas coloured ones are 2.2 uF based on the schematic.

The one that is supposed to be the 50 uF one may be 5 uF, since I could have sworn I saw 5 on it when I had it out. I will have to check again.

attachment.php
 

Attachments

  • Tangent XO.jpg
    Tangent XO.jpg
    84.7 KB · Views: 283
The colourful capacitors are 5% Mullard 250 volt Polyester components, so you do not :nono: need to replace them!

So you can spend lodsa money on the other four :D.

Only replace the resistors like for like as their inductances are important to the circuit.

The values on my schematics are correct btw and you read the Mullards like resistors i.e. black, brown, red = 2, orange = 3, etc.


:music:
 
Last edited:
Ok, cool thanks. Mullard... I thought they were just famous for their 12ax7. I just assumed 30 yr old + capacitors were a little tired. Apparently these were relatively expensive speakers at one time.

There are only 6 caps in the circuit. You mean the other 2? The red and black ones are the ones you should replace? I wasn't planning on replacing resistors since they don't really drift. The black and red ones are the 6 uf and the 50 uf, I confirmed those last night.

These speakers just seem a bit dark. I thought it was the caps, maybe its because they are British.

Upon google search I see that they are indeed "legendary Mullard tropical fish caps" Apparently I should be putting them in my guitar amp. Thanks again for the input.

Apparently the first two bands are the numbers, so a wide red band is two 2s, so 22. The next band is the number of zeros for a value in pF, so 5 zeros is 2200000 pF = 2200 nF = 2.2 uF if I have my SI prefixes correct. Which I believe I do, because I get to practice them with pico, nano, and micro molar DNA solutions all the time. Hooray PCR.
 
I was referring to the 50uF and 6uF electrolytics, you'll need 2 for each speaker 4 in all.

I'd replace the 50uf with another electrolytic (although you have got space for a fat component if you're using 100 W + amplifiers)) and use a 5.6uF Solen plus 2*0.2uF to make up the value to 6uF if you feel the need on listening.


:music:
 
Those black and red ones are in the woofer circuit it looks like. Should I expect to brighten up the speaker. Right now I am A-Bing it against my Advance V-II with the Solen caps.

I find the tangents are lacking mids really bad. They sound like the vocalist has a hand in front of his face.

I guess that makes sense if the crossover frequency is as high as 3 kHz.

That would be a 5.6 uF and two 0.2 uF caps in parallel. Capacitance is additive in parallel I'm pretty sure, its 1/x= 1/a +1/b in series. Am I right?
 
A new 6uF will brighten things up, as the red/black electrolytic turns into a resistor over time you loose bass/mid output.


Parallel banks of capacitors do allow larger values to be "made-up".


Solen have a Canadian website www.solen.ca/ so you can buy them direct from St Hubert, Quebec.

:music:
 
Last edited:
exhilaration157 said:
And now to find a store that is in Canada so I don't have to pay Customs and Brokerage fees of $30 for a $50 order!!!

and yes I did find one pretty close to home too. http://www.partsconnexion.com/
Click to expand...
The prices at the place you mentioned are outrageous!! Talk about diminishing returns! Check out Lee's Electronics in Vancouver. They do a booming mail order business. They sell Solen caps, 100V, 250V, or 630V at quite reasonable prices. They also sell Bennic, Orange Drop, metallized polyester caps, Wima and others.

www.leeselectronic.com
 
Haha, yeah I did see some pretty outrageous parts on there.

The Solens were are not that bad though. $3.95 for 6.2 uF 400 V metalized polyproplylene.

I guess I deserve a bit of a hard time for some comments I made in another post. But seriously I did not know that such expensive components existed. You can buy a house for what some of these systems cost, $4000 for a capacitor...:scratch2:
 
I got the caps today. It was a night and day difference. These speakers actually sound crystal clear. Wow!

I ordered 250V parts. The 51uF cap looks pretty big, but they fit fine. It's a pretty loose PCB. I ended up using PP caps of 6.2 uf and 51 uf. Those values are within 3% and that is close enough.

attachment.php
 

Attachments

  • solenTM3 XO.JPG
    solenTM3 XO.JPG
    96.6 KB · Views: 217
Hi there, I came across this thread while I was looking up some tangent tm3s that i recently found.
I noticed that the caps in my crossover are a little different than the ones pictured above. I wonder if anyone could help me identify them. Maybe they have been replaced in the past?
 

Attachments

  • tm3xo.jpg
    tm3xo.jpg
    87.7 KB · Views: 139
The UK range of Tangent speakers
I designed ALL the speakers made by Tangent Acoustics Ltd between 1974 and 1979. When the company collapsed I briefly manufactured speakers branded Beam, but then returned to teaching mathematics and physics.
Now I live in happy-but-hectic retirement in the peaceful county of Dorset.

Unfortunately, there is little that can be done for defective Tangent speakers, unless the exact same driver types can be found. Crossovers can be precisely rebuilt of course, but only if charred remains can be identified!

I am re-emerging because I have been quite touched by comments I have read, and because I might still be able to give some helpful advice and clarification. For example, I noticed in a different thread comment about the sound of the RS2 and RS4 being like the BBC LS3/5A. There is a very good reason for this!

I am, for myself, currently finishing off a pair of corner horns, very much like those I designed for Wireless World in 1970 and 1972, but now using Behringer Ultragraph Pro equalisers and class-D amplification.
 
Everyone went quiet after your reply, monteverdi. :) Thanks for a great design. We used to call these the poor man's KEF 104 and I have even heard that the crossover design was better. If you are still around could you answer a few general questions?
Were the drive units matched pairs?
Would you advise adding a tweeter fuse as per the 104ab?
Is it worth doing the ab redesign of the crossover I've seen elsewhere? (I can't find it now)
I assume you agree with the advice above to change only the electrolytics.
I have a pair of these TM1s and have noticed the stereo imaging is a bit vague and smeared. Any suggestions?
The deep bass is excellent, on a par with the 104s, but sounding a bit boxy. Would replacing the foam help?

It's a shame that most of these have been broken for the tweeters.
 
borosphere said:
Everyone went quiet after your reply, monteverdi. :) Thanks for a great design. We used to call these the poor man's KEF 104 and I have even heard that the crossover design was better. If you are still around could you answer a few general questions?
Were the drive units matched pairs?
Would you advise adding a tweeter fuse as per the 104ab?
Is it worth doing the ab redesign of the crossover I've seen elsewhere? (I can't find it now)
I assume you agree with the advice above to change only the electrolytics.
I have a pair of these TM1s and have noticed the stereo imaging is a bit vague and smeared. Any suggestions?
The deep bass is excellent, on a par with the 104s, but sounding a bit boxy. Would replacing the foam help?

It's a shame that most of these have been broken for the tweeters.
Click to expand...
monteverdi said:
The UK range of Tangent speakers
I designed ALL the speakers made by Tangent Acoustics Ltd between 1974 and 1979. When the company collapsed I briefly manufactured speakers branded Beam, but then returned to teaching mathematics and physics.
Now I live in happy-but-hectic retirement in the peaceful county of Dorset.

Unfortunately, there is little that can be done for defective Tangent speakers, unless the exact same driver types can be found. Crossovers can be precisely rebuilt of course, but only if charred remains can be identified!

I am re-emerging because I have been quite touched by comments I have read, and because I might still be able to give some helpful advice and clarification. For example, I noticed in a different thread comment about the sound of the RS2 and RS4 being like the BBC LS3/5A. There is a very good reason for this!

I am, for myself, currently finishing off a pair of corner horns, very much like those I designed for Wireless World in 1970 and 1972, but now using Behringer Ultragraph Pro equalisers and class-D amplification.
Click to expand...
I guess @monteverdi has left the building. :D

I have a pair of TM1s but like the RS4s better.
 
You must log in or register to reply here.
Back
Top Bottom