Beautifully crafted transmission cabinets, disappointing sound. Upgrade?

Jump to Latest
S

skyfire

Member
Joined 2022
#1
So i bought these beautiful locally crafted 8" transmission line speakers. The company is now extinct sadly. (but i got them for an amazing price because of that.)
The cabinets are stunning and very inert. Made out of Plywood with a native real wood veneer.

nRSHi5I.jpeg

Tweeter is a Dai-ichi DT-81 https://mega.nz/file/kQBQTDoS#qX3DtvMSzE9EnrmaVq-fWHBuMZocYfgWJGqBjSZi4M8
Mid - Response CW2192
Woffer - Response CW2196

Picture of the crossover for the mid and tweeter. Woofer just has a 9mH inductor in series.
https://mega.nz/file/sYQhWQRT#mv9-vGMiIxP4TJ5KTRLhibM3HcwISKbt7qlCMhEtpf8

Link to way-back machine achieve of Pure-sound websight.
https://web.archive.org/web/20160801014151/http://puresound.co.nz/?page_id=204
Unfortunately the High's somehow sound veiled, and also a bit fatiguing as well?

Because i got them for such good price, and the cabinets are so nice, i think upgrading them would be a good option.

Is this just a case of Finding a new tweeter that will physically fit, has a similar sensitivity, and desirable frequency response?

Any thought welcome.
Skyfire
 
Last edited:
#5
I would measure the speakers to see what's wrong. Changing the tweeter would be low on my list of priorities as long as it doesn't turn out that it was an inappropriate choice for the job. The same goes for the capacitor brands.
 
  • Like
Reactions: dangus
#6
AllenB said:
I would measure the speakers to see what's wrong. Changing the tweeter would be low on my list of priorities as long as it doesn't turn out that it was an inappropriate choice for the job. The same goes for the capacitor brands.
Click to expand...
I did do some VERY crude frequency sweeps just using my phone and the Spectroid app. The Dai-ichi tweeter doesn't really strike me as great quality. very plastic, and average motor.

The marketing material also goes on about a deflation circuit?

A diffraction circuit is also used in the SGM380. Diffraction occurs when frequencies which have a wavelength equal to or shorter than the width of the front baffle (usually 1KHz and above) diffract, thus boosting their loudness by 6 dB’s. This occurs in 99% of speakers which is why most speakers sound artificially bright when compared to live music. The circuit uses resistors and chokes to correct the diffraction, giving the speaker a far more transparent and natural sound.
Click to expand...

https://imgur.com/jiHEgEE
https://imgur.com/a/NRpUbAb
 
#8
Yellow is the noise floor (hot day, every fan going:hot:), red is the peek. I'll have time tonight to do a better screen capture.

Would just bypassing that final inductor on the tweeter circuit give me some more hi-end detail?

Thanks
 
#9
You should try it, no guarantees.

This is an expanded plot. Ignore the bass below 100Hz (on this plot). Up to just beyond 1kHz is OK for now.

Is it possible for you to take multiple plots, and overlay them on the same graph while not moving the microphone between measurements?

ru.png
 
Last edited:
#11
The outer dimensions of the box is 240mm x 240mm x 970mm that dosen't count the skirt/plinth. The tweeter and mid are in their own seald Enclose that's stuffed with poli-fill, so it's going to be a real challenge to give you an accurate volume.
 
#12
18mm material? Where is the terminus? Any insde partitions? We can ignore the little box for the mid. I am more interested in the line length and cross-sections. J can work that out from dimensions once you get inside. And the driver offset (distance from either end will do).

dave
 
#16
picowallspeaker said:
Probably the 1.8mH-30 Ω cell coes to the mid...
🤔
Click to expand...
I did have it in a fifferent place, but that combo sits just before the 32Ω 8Ω and the the 3.3µF cap to the tweeter.

Some of the connections are hard to make out and the shagows don’t help.

I expect the OP will need to go move some wires around and check to see what really hooks up to what.

The 0.05 fell into place at the end, it is strange,

dave
 
Last edited:
You must log in or register to reply here.
Top Bottom