I just bought a pair of unused Betsy-K's from a fellow that changed direction in his build.
At any rate, set them up to run in a bit to get some before/after TS measurements, and I have to say that just sitting in the open being fed from a Daytom DTA-100a, they sound wounderful on Diana Krall, Emerson Quartet, and some piano jazz.
The high sensitivity really jumps out as well. I only listened for about 10 minutes due to other constraints, but the inital impression was overwhelmingly positive. I am running in some other highly regarded 4" full rangers as well. While they sound good "naked", they certainly don't have the presence that the larger Betsy's bring. Looking forward to getting Betsy in a box.
Looking for suggestions that aren't BIB. I've modeled with w/ factory T/s in some 1 - 2 ft3 reflex and they look good. Haven't revised for measured specs which were close to factory except my measured VAS was quite different (~65liters to factory 81).
At any rate, set them up to run in a bit to get some before/after TS measurements, and I have to say that just sitting in the open being fed from a Daytom DTA-100a, they sound wounderful on Diana Krall, Emerson Quartet, and some piano jazz.
The high sensitivity really jumps out as well. I only listened for about 10 minutes due to other constraints, but the inital impression was overwhelmingly positive. I am running in some other highly regarded 4" full rangers as well. While they sound good "naked", they certainly don't have the presence that the larger Betsy's bring. Looking forward to getting Betsy in a box.
Looking for suggestions that aren't BIB. I've modeled with w/ factory T/s in some 1 - 2 ft3 reflex and they look good. Haven't revised for measured specs which were close to factory except my measured VAS was quite different (~65liters to factory 81).
which highly regarded 4" ?
I often catch flack for not liking the tb 1808 driver.
Eventhough the qts is lower than the betsy, I'd try the open baffle on the website
My wife had no problems with my 5' tall hinged baffles (unfinish baltic birch, driver 36" off floor, center panel 12", left panel 15", right panel 19"). Having the wings barely open beyond straight back with a foam box covering the back of the driver made for a narrow and pretty (sounded fine) setup.
Imagine the wings folded back so they are barely visible. My next hinged open baffle will be 6' tall, wings 24" wide, and center panel 12-16" wide.
Norman
I often catch flack for not liking the tb 1808 driver.
Eventhough the qts is lower than the betsy, I'd try the open baffle on the website
My wife had no problems with my 5' tall hinged baffles (unfinish baltic birch, driver 36" off floor, center panel 12", left panel 15", right panel 19"). Having the wings barely open beyond straight back with a foam box covering the back of the driver made for a narrow and pretty (sounded fine) setup.
Imagine the wings folded back so they are barely visible. My next hinged open baffle will be 6' tall, wings 24" wide, and center panel 12-16" wide.
Norman
Fastbike, have you run them a few hours? That VAS might go up a bit. 1-2 cu ft. seems pretty small for a vented box, but if you built 'em and thought they were boomy, you could always seal them up. Look at the Simple TL if you want something that doesn't take up too much space.
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
They haven't been run in yet, which is why I'm not cutting wood. Based on your recommended sizes, I was a bit surprised at the modeled response in a 29Liter sealed arrangement, but it was a flat curve w/ reasonable output and decent F3/F10.
I also looked at sealed/vented 61 liter and vented 81 liters. Right now vented 61 liters seems to be the sweet spot. As expected, quite a bit more output than sealed. Only a few Hz lower response. OB is out for me, don't have enough space anywhere that I can put speakers.
I have seen the simple TL and the Karlsonette designs.
The 4" FRs I was speaking of were the MArkAudio CHR-70.3 and CSS EL70s. I like them all, but the presence of the bigger Betsy's was immediately "present"
I also looked at sealed/vented 61 liter and vented 81 liters. Right now vented 61 liters seems to be the sweet spot. As expected, quite a bit more output than sealed. Only a few Hz lower response. OB is out for me, don't have enough space anywhere that I can put speakers.
I have seen the simple TL and the Karlsonette designs.
The 4" FRs I was speaking of were the MArkAudio CHR-70.3 and CSS EL70s. I like them all, but the presence of the bigger Betsy's was immediately "present"
although TB's 1772 has an extended and reasonably smooth on-axis treble, I prefer BetsyK's midrange in when both are compared in a small K-coupler
An externally hosted image should be here but it was not working when we last tested it.
Yes, I have seen your build thread and will probably do the XK8. I've never heard a Karlson (type) and am intrigued by the build.
Also, to Paul, I have run them in for about 25-30 more hours and Vas has dropped further (58L on one and 61L on the other). I really do like the sound.
With measured specs, 61 liters vented is a sweet spot.
Also, to Paul, I have run them in for about 25-30 more hours and Vas has dropped further (58L on one and 61L on the other). I really do like the sound.
With measured specs, 61 liters vented is a sweet spot.
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I'm fairly skeptical of the VAS going down with time. It doesn't make much sense to me, unless we're talking a long period of time and the suspension gets drier and tighter. But, your changes are pretty small. 61L isn't a big vented box for the BetsyK, but if it gets boomy you can always tune it a bit lower.
BTW: what 'foam box' are you talking about Robert?
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
BTW: what 'foam box' are you talking about Robert?
Paul
Wild Burro Audio Labs - DIY Full Range Speakers
Perhaps I haven't been clear. My measured Vas values aren't going down. They are consistent, they just haven't ever measured as large as the specs.
Both drivers are marked WBAL 114 w/ a 1/22/10 date on the back.
FWIW, if the box volume doubles to 4 ft# (111 liters), the F3 drops 4 Hz and the output goes up by 1.5dB but f10 doesn't change.
That's not a good trade from my perpsective, no real change in performance for twice the box volume.
Also frankly, if the box is tuned low (~34Hz) the F3 goes way up and the FR isn't nearly as flat. That also doesn't make any sense as a design choice.
Paul, your site says 2 to 3 ft3 ported, so I don't understand why my result seem to bother you so much. You can see the predicted response curve is quite flat so I wouldn't expect it to be boomy.
My experience with this box modeler is that it is a good predictor of results when measured T/S values are used.
Both drivers are marked WBAL 114 w/ a 1/22/10 date on the back.
FWIW, if the box volume doubles to 4 ft# (111 liters), the F3 drops 4 Hz and the output goes up by 1.5dB but f10 doesn't change.
That's not a good trade from my perpsective, no real change in performance for twice the box volume.
Also frankly, if the box is tuned low (~34Hz) the F3 goes way up and the FR isn't nearly as flat. That also doesn't make any sense as a design choice.
Paul, your site says 2 to 3 ft3 ported, so I don't understand why my result seem to bother you so much. You can see the predicted response curve is quite flat so I wouldn't expect it to be boomy.
My experience with this box modeler is that it is a good predictor of results when measured T/S values are used.
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