Questions regarding betsy's

[crazymexican]

Hello guys,

Well after a forced break from the forums ( gotta love that work stuff ) I'm back. Well a couple of weeks ago I bought a pair of betsys and this weekend I was finally able to put them to use.

I built the baffle that appears on the wild burro web page. so far I'm liking them but I am wondering, do these guys improve with burn in ??? and if so after how many hrs???

[zimmer64]

Mine have not after a about 100 hours. They have a significant peak starting from 1Khz to about 6Khz and drop a lot from about 12Khz, which makes voices sound forward and nasal. I am currently playing around with a miniDSP and two stereo amps to tame the midrange. On axis the highs are ok. Off axis a super tweeter might help. For bass support I am trying Eminence Alpha 15. I use a crossover freq. of 200Hz at the moment.

Best

Michael

[pjanda1]

Michael,

Are you sure your crossover phase is sorted? It sounds like you might have a problem with the upper bass.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers

[fastbike1]

FWIW, I don't have the same impression of forward, nasal vocals. I have found the BetsyK's to be pretty pleasant listening.

[zimmer64]

Originally Posted by pjanda1

Michael,

Are you sure your crossover phase is sorted? It sounds like you might have a problem with the upper bass.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers

I am a beginner in DIY, so bear with me :-)

I low pass the Eminence Alpha and high pass Betsy. I set the miniDSP to 12 db Linkwitz Riley filter at 200Hz. Is there anything wrong with that?

Best

Michael

[pjanda1]

Michael,

Keep in mind that the electronic slope will combine with the acoustical slope. Depending on how wide your baffle is, the Betsy will be rolling off somewhere on it's own. The Alpha could be doing any number of things. I'm aiming for a second order crossover at about 165 hz. To accomplish that, I have a first order crossover (single cap) on the Betsys (at line level) at right about that point (in combination with the baffle width), but on the woofers, I'm using the miniDSP with a 2nd order slope set much lower (maybe 80hz?), due to their rising response.

It really sounds like it isn't working for you, so there are three ways to approach it.

One is to measure. You can measure the system in whole and the drivers individually, both with and without the crossover. That'll give you an idea of what's happening. Of course, measuring is hard to get right, and you can misinform yourself that way too!

Second would be to run some models of the drivers on the baffle and see what it looks like. There are various software solutions, and I'm probably out-of-touch as to what the best free solutions are.

Third would be to experiment and see what happens. Try different slopes and crossover points. It does help to think about what you are doing a bit, especially regarding the fullrangers. You can end up working them too hard electrically to make up for acoustical problems. So, before you do any crazy EQing on them, I'd run through a bunch of different options on the woofers.

I did sort of a combination of 2 and 3, first looking at some simulations to see what was most likely happening, then playing with the miniDSP until it seemed to work out.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers

[zimmer64]

Paul,

Thanks for the tips. I shall give it a try and report back.

Michael

[zimmer64]

Hello,

I did indeed have a phase issue. So here is what I did. I changed to 4th order Linkwitz Riley and x-over at 200Hz. 4th order LR is in phase again..... That resolved the nasal sound. I also defined a +10db low shelf filter below 200Hz plus an additional +6db peak EQ at 100Hz for the woofers. I tamed Betsy at 2800Hz a bit and also applied a high shelf of +8db above 7000Hz. I have attached the frequency response at the listening position.

I am much happier with the sound so far. Staging and imaging are very good. Voices equally well so far. I will need to listen to more stuff now and see how I get on.

Again, thanks for your help.

Michael