Right now I have 31" from the front of my main speakers to the back wall. How do these XSD speakers fare when they can't be pulled out into the room 3' or more?
They sound great at 31in. That’s about what I have them at for my lab. Gather out improves stereo image as in any speaker. But the bass is open baffle/dipole so works quite well at this distance.
Some of the components are out of stock so I will need a few weeks before I can ship it. If that’s ok I’ll get it listed for you again.
I´m slowly progressing with my build using 8x 6.5" Dayton DC-160-8 woofers per side, which are 8 ohm nominal. I wanted to check in to confirm my wiring math is correct.
Diagram of woofers:
W1 W2
W3 W4
W5 W6
W7 W8
I will wire the woofers face-to-face in parallel, out of phase so both push in or out. So W1+W2 in parallel will yield a 4 ohm nominal load. same for W3+W4, W5+W6, W7+W8.
Then I would connect W1W2 + W3W4 in series leading to a 8 ohm load, and same for W5W6 + W7W8.
Then W1W2W3W4 + W5W6W7W8 in parallel for a final 4 ohm load for the whole bass section.
Is this correct?
What would be the math for the nominal sensitivity of this array? Each woofer has a nominal sensitivity of 86dB @2.83V/1m.
Thanks in advance!
Diagram of woofers:
W1 W2
W3 W4
W5 W6
W7 W8
I will wire the woofers face-to-face in parallel, out of phase so both push in or out. So W1+W2 in parallel will yield a 4 ohm nominal load. same for W3+W4, W5+W6, W7+W8.
Then I would connect W1W2 + W3W4 in series leading to a 8 ohm load, and same for W5W6 + W7W8.
Then W1W2W3W4 + W5W6W7W8 in parallel for a final 4 ohm load for the whole bass section.
Is this correct?
What would be the math for the nominal sensitivity of this array? Each woofer has a nominal sensitivity of 86dB @2.83V/1m.
Thanks in advance!
You have the wiring correct. The way to check is use a 1.5v battery to confirm movement of each section and then final check. All drivers should snap in and squeeze air out when positive battery to positive wires. It will be about 92dB at 2.83v so about same as using the nominal specified drivers.
Hello @xrk971
Slowly getting there. I have the first one wired.
Front panels are screwed to allow testing different widths.
Back wings are to be tested in different lengths/shapes, as I don't need to get supper low because I run subs.
Tomorrow I should be able to take some measurements. Measuring OBs indoors is always an issue for me. How did you take measurements? Speaker on the floor (vs elevated on a chair or something), mic at 1m from front panel, at mid height, no windowing when measuring and later apply a window?
Looking forward to this!
Slowly getting there. I have the first one wired.
Front panels are screwed to allow testing different widths.
Back wings are to be tested in different lengths/shapes, as I don't need to get supper low because I run subs.
Tomorrow I should be able to take some measurements. Measuring OBs indoors is always an issue for me. How did you take measurements? Speaker on the floor (vs elevated on a chair or something), mic at 1m from front panel, at mid height, no windowing when measuring and later apply a window?
Looking forward to this!
I’m guessing the panel is about 32 inches tall with 4 pair of 6.5” GRS…maybe the slot is 30 inches tall?
If he’s “rule of thumbing” the slot from the article Pa wrote it should be approximately 1/3 Sd (8 X 21.75 square in or 140.3 square cm).
At 30 inches tall the slot should be about 2 inches wide? Looks about right.
I’m curious to see the measurements with no/various wings.
If he’s “rule of thumbing” the slot from the article Pa wrote it should be approximately 1/3 Sd (8 X 21.75 square in or 140.3 square cm).
At 30 inches tall the slot should be about 2 inches wide? Looks about right.
I’m curious to see the measurements with no/various wings.
The total baffle height is about 45in tall. The woofer slots are 5.5in high x 2.25in wide and CTC spacing between woofers is 7.0in. Slot depth is about 6.5in.
I typically measure at 0.5m to mimimize floor bounce cancellation. Keep speakers at least 4ft away from a back wall. Set voltage drive to 2.0 vrms. This will be same as 2.83vrms at 1.0m.
Finally got around to measuring. I tried without wings and later with 6"wings (the panels from speaker #2) to get a feeling of the behavior, and measured on-axis, at 15°, 30°, 45°. Mic at 50cm and amp at 2V while checking level on REW turned out to be 90dB SPL at the mic measured with the handheld SPL meter.
Setup without wings:
With 6" wings:
Comparing on-axis with wings I get 2dB additional SPL at 70Hz.
As predicted by @xrk971 the response falls abruptly at 470Hz. At 470Hz the response is still 9dB higher than at 70Hz. This has me wondering if I should xo around 550Hz. I will be using active xo and Acourate to hammer down the response into the targeted house curve.
Setup without wings:
With 6" wings:
Comparing on-axis with wings I get 2dB additional SPL at 70Hz.
As predicted by @xrk971 the response falls abruptly at 470Hz. At 470Hz the response is still 9dB higher than at 70Hz. This has me wondering if I should xo around 550Hz. I will be using active xo and Acourate to hammer down the response into the targeted house curve.
I’m not sure why this has such a rising response. On my XSD, the raw response was relatively flat. Are you using the GRS 6.5in drivers?
I was wondering about the rising response as well. Drivers are Dayton DC160-8 6.5". The near field response of the drivers, from Dayton spec sheet, rises about 3dB from 70 to 200Hz. It doesn't seem to be the inherent response of the driver.
The DC160-8 has a powerful magnet and rather low Qts. This is probably making it behave differently under slot loading designed for a high QTs woofer. Since you are using DSP and EQ it would be easy enough to flatten. However, this would be a lot of attenuation and power thrown away in a passive crossover.
Recently wasnt feeling all the magic, attributed much to temporary demise of XA 252. Then while listening to some closely recorded
stand up bass, thought I heard the fluttering here or there of a damaged woofer. At first I thought it was an artifact of the recording,
but no something amiss.
Closer examination, I could hear the "roar" off the bass hit in the three lower vents, but the top vent was "roarless." I took off side panel, and while looking into the vent I could see the end of a wire that should have been connected to the outfiring woofer. I had turned the woofer to a less than ideal position for the wires to reach, and it eventually came off. Re attaching it and properly positioning.the woofer corrected all. Magic back!
Such a nice speaker.
Russellc
stand up bass, thought I heard the fluttering here or there of a damaged woofer. At first I thought it was an artifact of the recording,
but no something amiss.
Closer examination, I could hear the "roar" off the bass hit in the three lower vents, but the top vent was "roarless." I took off side panel, and while looking into the vent I could see the end of a wire that should have been connected to the outfiring woofer. I had turned the woofer to a less than ideal position for the wires to reach, and it eventually came off. Re attaching it and properly positioning.the woofer corrected all. Magic back!
Such a nice speaker.
Russellc
Firing 6 cylinders on a V8 (I meant flat 8 boxer) will do that to you! It sounds a lot worse than 25% drop for some reason.
Crazy Porsche 917 was a flat 12 boxer with turbo.
Crazy Porsche 917 was a flat 12 boxer with turbo.