Triangle 202 tweeter hi-pass upgrade

I saw that several folks here use Triangle 202 series speakers (I use Tituses).

I think *probably* all the tweeters have ~6.2kHz hi-pass filters on them, and the mid/woofers run with no filter (or just a hi-pass filter in the case of the 3-way systems).

Several years ago, I upgraded the parts in my filters, and would highly recommend it for a nice increase in smoothness & detail. I would say the cap is BY FAR the most important, but I went 'whole-hog' & did the inductor and resistor as well (and eliminated the protection widgets). I did the widgets first (no change noted), then the cap (rather large change), then the others (very little if any change).

The stock parts are glued on as well as soldered, so it is a small challenge to pry the darn things off, but it can be done. I actually cut up the stock coil with big dykes to help get it off ...!

I used AudioCap caps, but probably would use Auricaps if I did it now (~$26 for a 3uF 200V). I see they now make teflon versions for $200 !!!!!

A few minutes with some needlenose pliers, a soldering iron, & a glue gun (and $60 for the caps) is well worth it, IMHO.

 

Thanks for posting this Rick. I was going to PM you about it after you mentioned it in the triangle thread.

 

I just wanted to add (for those who want to try this) that I did try the filter as a simpler first-order (just the cap and resistor, no inductor, reverse leads to tweeter (I did also try both polarities)). I wondered if the first-order would give even more openness, etc..

I did not like the sound, it was more sibilant or something ... So I went ahead & did the inductor upgrade, etc.. There! Good sound again ...

I think the Triangle designers do know what they are doing!

Hmmmm ... do the upper-end models (Zerius , Antal, et al) have better components to start with? I bet the Comete had the same ones, but maybe they spent more than $0.50 on the caps for the better models in the line ...?

Also, again: the parts are glued on (I seem to remember it looked like they were sprayed with maybe very low-viscosity (hot?) glue or something?) so it is a challenge. I think I cut around the base of the cap to help in the process. It has been a long time since I did this. I think the board is thick enough to resist breakage, but be careful (use slow & steady prying), and proceed at your own risk ...

 

I'll get into my Zerius's in the next week or so and let you know.

 

....or maybe today

Here's the Zerius. EE202ZE instead of EE202TI. I have no idea what I'm looking at, but the Zerius looks a little "beefier".

 

Aha ... 'ZE' for Zerius, 'TI' for Titus. It certainly is a bit more 'stuffed'. I'm certain the black rectangular-cubic thing to the left is the tweeter cap. The white-bobbin coil (inductor) next to it is also part of the tweeter circuit, the white ceramic-coated (level matching) resistor is underneath, and the other larger inductor and ??? parts are the crossover for the midrange & woofer. The orangeish ceramic-cap looking thing (there may be two or 3 of them scattered around) are the protection 'widgets' I was talking about; they are auto-resetting thermal fuses, basically.

I am not certain of the exact crossover (hi-pass) frequency in this application. In the Titus, it was 6kHz. I actually tweaked this to 6.2kHz due to parts available at the time from Parts Express ...

Coil 0.260 mH (original); 0.22 mH (replacement)
Capacitance, uF 2.700 uF (original); 3.0 uF (replacement)
Xover F (spec) 6.00 kHz (original); 6.2 kHz (replacement)

With the cap tolerances, the change in frequency may not actually exist; I certainly didn't notice any problems.

I wonder if the Zerius spec F is a bit lower, due to a larger midrange driver? I think the driver is larger than in the Titus ... and I seem to remember the cap is NOT marked ... I don't remember how I arrived at the 2.7 uF spec for the original cap - maybe it was posted or something? ack, too long ago ...

Looks like a bit more of a challenge to put in a large cap in place of the original, and secure it by other than just the soldered leads. I could imagine hot-gluing the new cap onto the top edge of the white 'bobbin' of the smaller inductor (coil), then ty-rapping or simply tying it with twine or string onto the bobbin for added stability. The darn coil is soldered and glued onto the board, and it AIN'T going anywhere, even with a cap riding along ...

Anyway, I doubt the cap would pull loose even if it was just soldered in, but a little security/vibration suppression can't hurt.

So, the questions are: what is the design frequency/capacitance? and, if you want to go forward, do you have confidence in doing the mod? (or the naivete as I did just to go for it??!!!). Do you have a bud who has done some soldering/electronics work, maybe, that could help out?

I HAD done a bunch of mods on a tube amp before I did mine, so was pretty sure I could do it & get myself out of trouble if something went wrong (but THANK GOODNESS nothing really did go wrong, like a broken circuit board !!!). And I wasn't overly concerned about scratching things up a little, as I was definitely going to keep these forever ...

Well, I donno if I helped here or not, but I hope so. It may be better to wait in this case rather than mess up your new speakers (and especially before you get your new amp! )

Reply, PM or e-mail me at [email protected] if I can help further. - Rick.

 

Aha! "Sam" says the tweeter does come in at 6kHz in the Zerius as well. So it is most likely a 2.7 uF cap. I think a 3 uF might possibly work as well, but it would lower the design F to 5.7 kHz.

I would *think* this would be OK, but am not 100% certain. I think going higher (as I did) is OK since you aren't asking the tweeter to reproduce outside the original design band, but 5.7 kHz IS a little lower than originally intended ... probably best to stick with 2.7 uF.