What phase has such shape hehe. I think it is FR intended for a comparison (it belongs to X's 10F FAST). I remembered X mentioned the color as GRAY while in my screen it is LIGHT BLUE.
Look at the legend on the bottom. Light blue is the active LR2 10F/RS225 FAST response with Linkwitz transform for comparison.
The impulse response is obtained from the sweep data. So whatever power you were running the sweep at. An ideal impulse function is infinite power.
Yeah, I got that. I had to adjust the settings to clean it up though, it looked really noisy. I think I got it working
Read that Audiophile article on step response. Your SR actually looks decent - it is supposed to be a right triangle with a slope down like yours, the wider the decay the better. If your speaker has response down to 10Hz then the triangle would be about 100ms wide. When time alignment is not perfect the sharp leading spike is not aligned with the hump from the woofer and mids. You have reflections or diffraction edges near your driver about 3ms from tweeter.
Thanks! Yes, I know about the reflections. You can see the window(dashed line) that I had set. I figured the junk to the right is reflections.
Which is the sharp leading spike and which the hump from the woofers? I assume you mean how it slightly leans forward.
This is from a design from last summer and I doubt these are even final measurements, but more in progress. It's just something I pulled up to see if I could get the step to show in REW
The link in the middle of post #58.
http://www.diyaudio.com/forums/full...4-rs225-8-fast-ref-monitor-6.html#post4310620
Cymbals on soft dome tweeter vs 10F fiberglass cone fullrange
Here is an 11 second sound clip of some drums and cymbals action in .mp3 recorded from 2 sources:
(1) the JBL LSR305 which has a textile soft dome tweeter mounted in a waveguide with bass provided by a 5in woofer in a bass reflex cabinet, active internal DSP XO @ 1725Hz;
(2) the 10F/8424 and RS225-8 FAST with an active LR2 acoustic XO at circa 350Hz.
Change the .asc extension to .mp3 in order to listen.
Edit: previous file versions were incorrect.
Here is an 11 second sound clip of some drums and cymbals action in .mp3 recorded from 2 sources:
(1) the JBL LSR305 which has a textile soft dome tweeter mounted in a waveguide with bass provided by a 5in woofer in a bass reflex cabinet, active internal DSP XO @ 1725Hz;
(2) the 10F/8424 and RS225-8 FAST with an active LR2 acoustic XO at circa 350Hz.
Change the .asc extension to .mp3 in order to listen.
Edit: previous file versions were incorrect.
Last edited:
xrk971,
Congratulation new waveguide toys
and thanks sharing data. Will you break guarantee by taking it apart and try improve the distortion parameters .
Think both sound clips sound good, cymbals has very different contour the two between and impossible to judge which is the right one but leaning to 10F because expect that has 180º phase turn down about 500Hz area and the new one has double 360º phase turn around 1725Hz. The contour difference for me is like being in a music store testing sound differences cymbals between.
satx,
Own you a answer why it was about 3" offset. The minDSP setup slopes that i tried to target with the simple cap/coil had 10F setback if remember right 0,22mSec. Then when xrk971 did setup the passive XO live it had that awful mid boost, and when in XSim i did set back woofer 3" (0,22mSec) it showed same response as xrk971 did measure live.
Congratulation new waveguide toys
and thanks sharing data. Will you break guarantee by taking it apart and try improve the distortion parameters .Think both sound clips sound good, cymbals has very different contour the two between and impossible to judge which is the right one but leaning to 10F because expect that has 180º phase turn down about 500Hz area and the new one has double 360º phase turn around 1725Hz. The contour difference for me is like being in a music store testing sound differences cymbals between.
satx,
Own you a answer why it was about 3" offset. The minDSP setup slopes that i tried to target with the simple cap/coil had 10F setback if remember right 0,22mSec. Then when xrk971 did setup the passive XO live it had that awful mid boost, and when in XSim i did set back woofer 3" (0,22mSec) it showed same response as xrk971 did measure live.
Byrtt,
I know a lot more mid and HF power comes from the 10F as you can really feel the cone move and vibrate. The dome on the other hand, has no perceptible vibration as sound above 1725Hz doesn't require much movement. A more fair test would have been to XO the 10F at 1725Hz as a pure tweeter rather than mid tweeter. But that is part of the magic of FAST - to keep all the phase coherency in one driver through the telephone band. I just find the 10F to be more impactful and have authority behind its percussion. Part of it may be the better step response compared to the LSR305.
I won't mod the LSR305 - it is what it is and I need to accept its limitations and what it can do very well: Polars. It had given me an appreciation for how much technology and engineering one can get for a very reasonable price. JBL did a very nice job here.
I know a lot more mid and HF power comes from the 10F as you can really feel the cone move and vibrate. The dome on the other hand, has no perceptible vibration as sound above 1725Hz doesn't require much movement. A more fair test would have been to XO the 10F at 1725Hz as a pure tweeter rather than mid tweeter. But that is part of the magic of FAST - to keep all the phase coherency in one driver through the telephone band. I just find the 10F to be more impactful and have authority behind its percussion. Part of it may be the better step response compared to the LSR305.
I won't mod the LSR305 - it is what it is and I need to accept its limitations and what it can do very well: Polars. It had given me an appreciation for how much technology and engineering one can get for a very reasonable price. JBL did a very nice job here.
hello X - guess you've seen this inductor mod - ? http://www.amazon.com/review/R139AJ7D7DFSAQ