Pass Labs B4 crossover questions

[WBS]

I wouldn’t complain. Am awaiting its arrival to bi-amp these beauties (SIT3 on top, Japanese dual mono MOSFET AB on the bottom.

An externally hosted image should be here but it was not working when we last tested it.

dave

Dave, those are BEAUTIFUL!

What's that thing along the edge near the top?

 

[planet10]

A7.3eN in a midTL, 2 x SDX7eN sealed. I sketched up a polygonal box and Chris, wanting to play with curves and vacuum bagging created these beauties.

dave

 

[feds27]

A7.3eN in a midTL, 2 x SDX7eN sealed. I sketched up a polygonal box and Chris, wanting to play with curves and vacuum bagging created these beauties.

dave

You said sealed but what is the dark grey section on n the side? Looks like foam in a side port/vent. Very nice looking baffles remind me of the Infinity IRS. Was there a specific curve used on the baffle? I’ve been debating making a curved baffle for my SLOBs. I believe the TAOB (Tiny Alnico Open Baffles) had a slight curve to their baffle.


Regarding the topic of the thread...
I’m waiting on the B4 too but in all fairness to Nelson, we could technically use the LXMini crossover in the meantime by adjusting some of the values. It may not have the flexibility of the B4 with regards to slopes and on-the-fly pots/dip switch adjustments but it could work.

 

[adason]

dave, for the cabinets so shallow, how do you prevent back reflection?

 

[planet10]

You said sealed but what is the dark grey section on n the side? Looks like foam in a side port/vent.

The top part — parallel to the top and from just below the A7 — is a midTL for the midTweeter. It is damped aperiodically and you do see foam at the mouth.

Was there a specific curve used on the baffle?

It was the curve defined by the 1st 30°, then 45° giant chamfers i had originally sketched.

for the cabinets so shallow, how do you prevent back reflection?

The distance behind the midTweeter turned out to be sufficient, the woofers do not go high enuff for the shallowness to be an issue.

dave

 

[Telstar]

I'm patiently waiting. Other projects took the priority in my queue

 

[noviygera]

I have waited for a while and I will continue to await. But if the possibility of making it a DIY reality comes, I'd be one of those who would embrace it at the first chance.

 

[adason]

No need to wait. Mine is already in the box working perfectly. The board can be adopted to any need.

 

[Telstar]

No need to wait. Mine is already in the box working perfectly. The board can be adopted to any need.

You have the pcb?

 

[adason]

If you're in a hurry and you only need 1 or 2 poles, you can get the LXmini
basic board + fets in the store.

 

[Nelson Pass]

The pc board BIAMP 6-24 XVR V1R1 is out for fab. Should be available in
the store April.

All four optional poles of each filter are independently adjustable by pots
over 2 octaves, and there is only one film capacitor value to select frequency range.

 

[WBS]

Well, my TADs perked up their ears when I read this post to them.

 

[mordikai]

Is there adjustable gain on the low and hi outputs or just the lows? What's the range of adjustment. Very excited thank you!

 

[cubicincher]

This sounds like a Easter present...


Greets
Dirk

 

[Telstar]

This sounds like a Easter present...

Really

 

[Nelson Pass]

Is there adjustable gain on the low and hi outputs or just the lows? What's the range of adjustment. Very excited thank you!

Both.

 

[Kang Kel]

In regards to a simple 2nd order biamp application:

If this is all that I need is there any benefit in holding out for this new release? Even though this new design will have greater adjustability is it going to be audibly better then the lxmini x-over kit?

 

[Studley]

Both.

Excellent, now make my day complete and tell me it supports balanced inputs and outputs, please . . . ?

 

[Nelson Pass]

No. You have to do that externally, or use two of the crossovers.

 

[Kang Kel]

Is any one able to confirm that if I only require a 2-pole high/low pass then there is no benefit in waiting for the DIY B4 Board. Or is the DIY B4 a better bit of kit then a modified LXmini x-over.