CHBW-70 Markaudio's new bass-wide

[markaudio]

Hi Guys,
Here's the data for the CHBW-70 Gen. 1.
I've based it on the CHP driver but with subtle changes inside the power-trian to make a driver suited to crossing around 4-kHz to 5-kHz. I've clear the upper ranges by changing the coil design. For the 2 way guys, this driver will make a nice unit for small to medium sized applications.

Like the CHP, the vocals are its main strength, (classic-semi vintage) sound. Anyone with my Tweet No.6 will find the CHBW a nice partner driver.

Cheers

Mark.

CHBW-70 Gen. 2 Data
REVC 7.2 Ohm
Fo 66.4 Hz
Sd 5.02 K mm/2
Vas 4.60 Ltrs
Cms 1.26 uM/N
Mmd 4.30 g
Mms 4.50 g
BL 4.43 G/cm
Qms 1.78
Qes 0.69
Qts 0.49
Levc 44.53 uH
No 0.19%
Spl 84.80 dB
Pwr 20w Nom.
X max 4-mm 1 way
Coil Dia 20-mm
Main tolerance +/- 2hz on mean Fo

[ultrakaz]

Based on the graph, this is a driver that really needs to be heard before determining on how to optimize it. It just might sound pretty good by itself, at least on vocals as you have attested to. The "built-in" lowpass probably needs to be massaged to get a balanced integration with a tweeter if crossed <5kHz.

Or, perhaps, used as the rear driver in a dipole with the CHR on the front.

[tresch]

Despite having a falloff in the upper frequencies, what benefits do you feel the new coil design would have?

More power handling? Lower Resonance? (I could certainly look this up myself I know) Perhaps reduced distortion at lower frequencies and with greater excursion?

[markaudio]

Originally Posted by ultrakaz

Based on the graph, this is a driver that really needs to be heard before determining on how to optimize it. It just might sound pretty good by itself, at least on vocals as you have attested to. The "built-in" lowpass probably needs to be massaged to get a balanced integration with a tweeter if crossed <5kHz.
Or, perhaps, used as the rear driver in a dipole with the CHR on the front.

Hi Ult, Guys,
For ANY Diy build 2 way and multiway systems, I'd always recommend gentle break-in and and a good listen to the drivers before installation.

I well remember listening to my Tweet No. 6 and comparing it to other budget tweets before going to production. I modeled No.6's tone and pitch by comparing to the wonderful 3.5 cm HF driver in Vintage Victor SX 500's (I have 2 mint pairs of these speaks).

Anyway, I'd personally start with a 1st order and work up from there. The CHBW's response is pretty much flat to 5-kHz, deliberately so to make it easier to partner.

Thx
Mark.

[markaudio]

Originally Posted by tresch

Despite having a falloff in the upper frequencies, what benefits do you feel the new coil design would have?

More power handling? Lower Resonance? (I could certainly look this up myself I know) Perhaps reduced distortion at lower frequencies and with greater excursion?

Hi Tresch,
Controlling distortion/linearity is the main gain. The objective is to make the response as flat as possible to help the matching process.
Thx
Mark.

[rikvancoolwijk]

do you have a Tweet No.6? I'm familiar with your Tweet No.3(great value for the money!)

Rik

[markaudio]

Originally Posted by rikvancoolwijk

do you have a Tweet No.6? I'm familiar with your Tweet No.3(great value for the money!)
Rik

Hi Rik,
My mistake, I meant Tweet No. 3. I'm hoping to make another batch soon as we've sold out. Paired with the BW in an 8 litre 2 way box, should be a nice combo.
Thx
Mark.

[rikvancoolwijk]

still have 2 pairs laying around, nice tweeters as they pair up with a lot of speakers so eazy!

Cant wait for the new gen CHBW, CHR, CHP and the new alpairs to come to Holland

Rik

[CSS/XBL]

Hi,

We are playing with this pair using a first order crossover at 4200kH in a 7 litre cabinet. Will also have to experiment with different port specs to see how it sounds best.

Stay tuned.

Bob and Jim

[roger_lew]

Bob and Jim. Thanks for verifying that the ERT26 is the Tweeter No. 3.

I've been thinking about a 2/3 way active system with Usher 8945p woofers up to 350Hz and either the CHBW/ERT26 or the Alpair 6p. I'm thinking the Usher 8945p would be ported in a large vintage-style bookshelf (e.g. Harbeth HL5 size: 25"T x 12.5"W x 12"D) where baffle step would coorespond to match the XO frequency. For amplification, I'm envisioning a LM4780 (stereo chipamp) with +/- 28 VDC rails for each channel with line level crossovers. For the price of decent passive components, I figure I might as well just build amplifiers into the cabs. The chipamp should be fine with 4 or 8 ohms and have enough power for the Usher.

Any thoughts on the CHBW/ERT26 vs. the Alpair 6p? Another contender was the Fostex FF85WK, but the power handling and excursion isn't up to snuff for this particular application. The goal is to have a reasonably compact speaker with decent extension and superb midrange that also has some headroom (100-102 dB peaks). They will be in a decent sized room and have a listening distance of 3 to 4 meters.

Thanks,
Roger