Author Topic: WL3 going green - an update  (Read 2112 times)

Offline bbe22

WL3 going green - an update
« on: February 24, 2015, 08:20:43 PM »

Offline bbe22

Re: WL3 going green - an update
« Reply #1 on: February 24, 2015, 08:21:36 PM »
WL3  showed me  enough potential to warrant a second version /  further tweak /  upgrade,  in the form of a new tweeter




This is an interesting if not often used variation of the nipple dome , and it performs very well if a higher X-over point can be realized. (3.5 K here). One DIY  speaker guru from the US likened it as having 80% of the performance of a Hiquphon for a third of the price.

Offline bbe22

Re: WL3 going green - an update
« Reply #2 on: February 24, 2015, 08:22:30 PM »
The diameter  of the new tweeter is smaller , so I made a flange insert to accommodate.




and started on the  new crossover.

Offline bbe22

Re: WL3 going green - an update
« Reply #3 on: February 24, 2015, 08:23:15 PM »
These changes happened just prior to the DIY Audio showcase 2014 and the WL3 actually played on a prototype  X-over at the event.

http://www.avforums.co.za/index.php/topic,25344.345.html  see pp24

It was the smallest speaker presented for demo on the day and the result was pretty average.

Ian (Jimgore) was brave enough to point out the mid was the possibly weak link this design.

Later evaluation  back home showed the integration between bass and mid had a considerable suck out with the variation of  X-over as presented. This was as a result of less than optimum (bad) data   (measurement indoors off the ground (400mm))  {time running out before the event}
 Lesson learned - with a bass unit so close to the floor pay special attention........

The grey colour of the box also showed a little wear and tear after travelling and I decided to redo the coating

Offline bbe22

Re: WL3 going green - an update
« Reply #4 on: February 24, 2015, 08:24:29 PM »


Offline bbe22

Re: WL3 going green - an update
« Reply #5 on: February 24, 2015, 08:25:01 PM »


Offline bbe22

Re: WL3 going green - an update
« Reply #6 on: February 24, 2015, 08:25:38 PM »
A fresh set of measurement data was taken

and the X-over was redesigned  from scratch   eliminating the known problem area.

......... measured to make sure

Offline bbe22

Re: WL3 going green - an update
« Reply #7 on: February 24, 2015, 08:26:35 PM »
Xover  Still a tight fit in box  ..........close to 2nd order @ 350  &  4th @3500 , bass connected out of phase


Offline bbe22

Re: WL3 going green - an update
« Reply #8 on: February 24, 2015, 08:27:23 PM »
  Freq and phase  (data  < 300 Hz approx  only)


Offline bbe22

Re: WL3 going green - an update
« Reply #9 on: February 24, 2015, 08:27:58 PM »
Outside 250 ms measurement shows true lower freq graph for  bass -  good output to 35 Hz

« Last Edit: February 24, 2015, 08:34:00 PM by bbe22 »

Offline bbe22

Re: WL3 going green - an update
« Reply #10 on: February 24, 2015, 08:28:30 PM »
and the polar plot  (+ / - 40 degrees) which I am particularly happy with


Offline bbe22

Re: WL3 going green - an update
« Reply #11 on: February 24, 2015, 08:29:04 PM »
Still a nominally 4 ohm speaker but a easy load on various amps tried, and quite benign phase angles   (Re = 4.7 ohm)  Box tuned to 35Hz, also the bass driver's Fs
« Last Edit: February 24, 2015, 08:34:37 PM by bbe22 »

Offline bbe22

Re: WL3 going green - an update
« Reply #12 on: February 24, 2015, 08:29:56 PM »
The version using the Dayton silky tweeter was also updated using the same bass and mid approach as the above.

So.....how does the two versions differ in sound ? I would say its close , but the XT19 is a  polished performer and gives that extra little clarity

This design is now mature / done   / finished and I am moving on to to other projects........

ps

This pair visited Sean S' place late in Jan. His listening  area is well sorted and it was a privilege to listen to his latest  3 ways  reported on recently. ( The WL3's played well too!)

pps
 forum members who would like to hear or try these are welcome to pm me (Western Cape  / West coast )

Brian
bbe22
Feb 2015

Offline Atjan

Re: WL3 going green - an update
« Reply #13 on: February 24, 2015, 08:37:30 PM »
Nice! These are very interesting speakers to me, especially with the near ob arrangement on the mid. I actually thought that was what reduced the lower midbass at the diy gtg. At the time it was a very obvious shortcoming and I would actually like to hear them again with the new xo. From the fr one can see that is now thoroughly sorted out though. :2thumbs:
It's only hifi people....

Offline JimGore

Re: WL3 going green - an update
« Reply #14 on: February 24, 2015, 09:37:36 PM »
Well done!  That transfer function looks decent to me, and the impedance plot looks benign and not too hard to drive  :2thumbs:

I also like that gentle downward slope as frequency increases - it gives the speaker a more laid back and easy character which I prefer.

How does it sound now - happy with it?

Kind Regards,
Ian.