|Multi-Way Conventional loudspeakers with crossovers|
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
||Thread Tools||Search this Thread|
|7th June 2011, 04:39 PM||#1|
Join Date: Dec 2007
Location: Melbourne the sunny city!
Vifa DQ25 Phase Shield removal surgery ...!
I'm building a rigid cone version of my dipole panel and decided to use Fountek FW146 and Vifa DQ25. While I immediately fall in love with FW146, the same cannot be said about the popular DQ25. It sounded "hard" for the lack of better word.
I suspected the phase shield is the issue and is a compromise between trying to maintain flat on-axis respose vs. other anomalies. So I removed one and measure it just to see.
On axis response
Measured from about 20cm on-axis, here we can see the effect of phase shield. It brought back the dip of typical rigid cone tweeter, but overall cannot remediate it fully. I'd say it's marginally useful.
Things gets more interesting here. Now we see the compromise, which is poor off-axis response. No phase shield is better by miles.
This one is I think the real reason why original DQ25 won't sound smooth. It's all the resonances, stored energy, and reflection of that hard phase shield.
So I proceeded to remove all the phase shield of the 4 tweeters. The subjective impression is more mellow sounding tweeter and a bit loss of "immediacy" as in steel guitar strings
In case you want to try, be careful in removing the shield as it is very close to the cone. I managed to dent one of the 4 tweeters ...
|Thread Tools||Search this Thread|
|Thread||Thread Starter||Forum||Replies||Last Post|
|Vifa D27 or DQ25 ?||gainphile||Multi-Way||22||6th April 2010 01:25 AM|
|Yamaha Surgery||jackinnj||Everything Else||5||15th July 2009 05:12 PM|
|Vifa DQ25SC16-04 phase shield||454Casull||Multi-Way||1||5th May 2009 03:46 AM|
|Toroid transformer, shield or not to shield?||bays_9a5tt||Digital Line Level||10||21st December 2008 02:10 PM|
|Spider surgery - anyone?||Jorge||Multi-Way||6||11th November 2005 09:11 PM|
|New To Site?||Need Help?|