Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Multi-Way Conventional loudspeakers with crossovers

Stephens Trusonic 120cx speakers - Best type of enclosure design?
Stephens Trusonic 120cx speakers - Best type of enclosure design?
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 11th August 2019, 09:09 AM   #21
vishalk is offline vishalk  United Kingdom
diyAudio Member
 
vishalk's Avatar
 
Join Date: Mar 2017
Location: North London
trusonic2.png

This is the other driver measurements. The added mass was 135g this time so 1g off, either way the results seem to match. I believe these drivers were hardly used GM they seem almost brand new probably need to be broken in and used.

* This data was exported from the Dayton Audio Test System: DATS
*
* Piston Diameter = 279.4 mm
* f(s)= 41.05 Hz
* R(e)= 7.182 Ohms
* Z(max)= 65.94 Ohms
* Q(ms)= 5.069
* Q(es)= 0.6196
* Q(ts)= 0.5521
* V(as)= 264.8 liters (9.352 cubic feet)
* L(e)= 1.133 mH
* n(0)= 2.819 %
* SPL= 96.6 1W/1m
* M(ms)= 29.97 grams
* C(ms)= 0.502 mm/N
* BL= 9.466
* K(r)= 0.1625
* X(r)= 0.4305
* K(i)= 0.01968
* X(i)= 0.6305
*
Attached Files
File Type: txt trusonic2.txt (11.9 KB, 0 views)

Last edited by vishalk; 11th August 2019 at 09:14 AM.
  Reply With Quote
Old 11th August 2019, 09:33 AM   #22
johnsurnamerobinson is offline johnsurnamerobinson
diyAudio Member
 
Join Date: Nov 2018
If the data is good,It looks more like an instrument or pa speaker, rather than a hi-fi woofer.
  Reply With Quote
Old 11th August 2019, 11:10 AM   #23
vishalk is offline vishalk  United Kingdom
diyAudio Member
 
vishalk's Avatar
 
Join Date: Mar 2017
Location: North London
Found these pictures of some enclosures using the trusonic, other pics are of the goodmans cabinets with the ARU 172


box-l-dj4f6jrhyaw66iuapcvermpbcq-1001.jpg

lion_hi_fi-img599x414-1437573450xvxtyz27166.jpg

lion_hi_fi-img599x338-1437573450dxapbq27166.jpg

646004-321342-img-0283-gthycvlzrnr1am_3nwuo.jpg

646003-321342-img-0282-1vcacescw6gi1qz17qhc.jpg
  Reply With Quote
Old 12th August 2019, 12:24 AM   #24
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
Thanks! Sure seems that way, what with its high efficiency and especially if coupled to a high output impedance tube amp and likely would never break in if used as a [family] room/whole house ~Muzak system like was common [at least in the USA] till hard rock[abilly] came along [not so much Elvis or even the Beatles, but CCR, Pink Floyd, et al].

That said, I remembered having a list of randomly measured drivers dating from back in '71 when T/S was starting to become known to the general public and lo n' behold got close [or so I assumed] with 120FR [CK], 120W woofers, but the specs are so incredibly far off from yours [and each other!] made me wonder, though were measured with a < 30 Hz Fs and otherwise not surprised of these 'world's apart' specs either, so once [re]broken in could in theory drop this much. Then again, the secondary surround may not let it, but 'hope springs eternal'.

This also made me take a look at the DATS screen and immediately saw a potentially major problem depending on how the DATS is programmed, i.e. what all does it use the inputted Piston Diameter for as it's way off? He asks rhetorically since they will need to be remeasured to find out.

Browse this T/S tutorial to see how much effective piston area [Sd] impacts specs: Thiele Small parameters equations - How each one affects the others

11" is wide enough for some 15" with < 10" [9.7"/9.6"] for a 12" frame being the norm for this style surround plus will be even shorter once at least half of the center surround is subtracted.

GM

Vintage published specs: ASHLEY
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.

Last edited by GM; 12th August 2019 at 12:29 AM.
  Reply With Quote
Old 12th August 2019, 12:35 AM   #25
bentoronto is offline bentoronto  Canada
diyAudio Member
 
Join Date: Jan 2008
Location: Toronto and Delray Beach, FL
Stephens Trusonic 120cx speakers - Best type of enclosure design?
Quote:
Originally Posted by johnsurnamerobinson View Post
If the data is good,It looks more like an instrument or pa speaker, rather than a hi-fi woofer.
Then you must be right: the data are bad.

My Stephens 150W (15-inch) was within a few Hz's of stock spec (about 22 Hz) after 50+ yrs (and maybe spot on, had I measured the resonance back then).

Beats me why low resonance drivers are harder to find today when the resonance pretty much defines the low-end reach.

(OK, the reason is so manufacturers can have heavy voice coils and claim the same power handling capacity as my kitchen toaster.)

As far as sealed boxes, the bigger the better and I'll stick with that.

B.
__________________
HiFi aspirations since 1957. "When the toilet paper of experience is depleted, the **** of reason goes unwiped"
  Reply With Quote
Old 12th August 2019, 03:27 PM   #26
vishalk is offline vishalk  United Kingdom
diyAudio Member
 
vishalk's Avatar
 
Join Date: Mar 2017
Location: North London
IMG_20190812_161237.jpg

IMG-20190812-WA0007.jpg

IMG-20190812-WA0009.jpg

Well guess i got to do it the old school way of just using my ears and what i have available.

Pair of folded horn enclosures which i got really cheap, were built by a BBC engineer, originally houses some decca tweeters and goodmans axiom 301's.

Have to rebuild them but for testing purposes the Trusonics will fit straight in and i can do some listening and use REW to do some analysis.
  Reply With Quote
Old 12th August 2019, 03:52 PM   #27
bentoronto is offline bentoronto  Canada
diyAudio Member
 
Join Date: Jan 2008
Location: Toronto and Delray Beach, FL
Stephens Trusonic 120cx speakers - Best type of enclosure design?
With the overwhelming effect of room acoustics, etc. on the final sound hardly worthwhile obsessing about planning every detail. Use REW and see what you have (testing drivers/speakers individually with no XO but at low power*) and use DSP to get what you want.

B.
* the woofer should be great but only guessing how that fancy tweeter will work today; unlikely you'll want to keep whatever thingy Stephens used as a crossover
__________________
HiFi aspirations since 1957. "When the toilet paper of experience is depleted, the **** of reason goes unwiped"
  Reply With Quote
Old 12th August 2019, 09:00 PM   #28
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
Quote:
Originally Posted by vishalk View Post
Well guess i got to do it the old school way of just using my ears and what i have available.
So not going to remeasure with smaller piston diameter?

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
  Reply With Quote
Old 12th August 2019, 09:46 PM   #29
vishalk is offline vishalk  United Kingdom
diyAudio Member
 
vishalk's Avatar
 
Join Date: Mar 2017
Location: North London
Yes will do GM, just want to put these in an enclosure and hear them, as for the piston diameter I followed the dayton online video.



I pretty much measured what they asked which was actually the cone diameter, why they called it piston diameter in not sure.



I didn't measure from the basket just from the outside rim of the surround(apex of the surround) which was 11".


I'll measure from the basket rim and do the measurements again, I'll also try different weights for the mass.



Where will this all lead though, will the results lead me to designing a suitable enclosure based on the measurements?


YouTube


See the parts express how to video
  Reply With Quote
Old 12th August 2019, 10:47 PM   #30
GM is offline GM  United States
diyAudio Member
 
GM's Avatar
 
Join Date: Jun 2003
Location: Chamblee, Ga.
Hmm, they're apparently making the assumption that since it's a tiny signal that it won't move enough to be considered shorter than when measured flat between the gaskets with no holes rather than effective diameter based on [Sd], which will make it narrower, putting it ~ in the middle of the surround and in this driver's case, omitting the same [Sd] for the tweeter and its surround, so at the very least it seems like the tweeter's diameter should be subtracted from the 11".

Regardless, it converts the diameter to m^2, so to my way of thinking this must be the same as its Sd [effective piston area], making my way to get the PD a lot more accurate, though without doing the math not sure how much difference it makes to the specs beyond efficiency.

edit: note that ideally the amount of added mass required will lower Fs by 1.56x [Fs*0.641] and due to its construction put it evenly distributed around the inner surround's point of attachment to the cone.

GM
__________________
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.

Last edited by GM; 12th August 2019 at 10:56 PM.
  Reply With Quote

Reply


Stephens Trusonic 120cx speakers - Best type of enclosure design?Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
For sale Stephens Trusonic 120 CX speakers and cabinets Shoreguy Swap Meet 22 2nd August 2018 11:34 PM
Stephens Vintage TruSonic 120 CX Speakers - What to do? Shoreguy Full Range 27 20th July 2018 10:24 PM
Stephens Trusonic 80fr Enochrome Full Range 28 25th October 2017 12:44 AM
Stephens Trusonic 50FR dobias Full Range 0 12th January 2012 11:59 AM
Stephens Trusonic Recone Bran Kulez Full Range 0 27th January 2011 04:01 AM


New To Site? Need Help?

All times are GMT. The time now is 06:34 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki