Pass Labs B4 crossover questions

[Nelson Pass]

The HPD succeeded the Monitor Gold some time in the 70s. The tweeter / horn remained little changed across many generations of the vintage Tannoys, and the HPDs and Golds have pretty much identical circuits for the tweeters in their crossovers. The earlier Reds didn't have a notch filter, so I guess they had a nice peak in their response.

My error. I have the HPD's, but the frame was painted gold.....

 

[feds27]

I will begin issuing pc board artwork for fabrication next month. The initial
offerings will be pc boards with matched Jfets.

These will likely expand to kits with full parts shortly after.

Excited to see a B5 kit will be made available. Curious if the Galaxy will be offered with pre-punched holes and what brand Jfets will be included in the kits.

Thanks for sharing the design with us.

 

[Nelson Pass]

Excited to see a B5 kit will be made available. Curious if the Galaxy will be
offered with pre-punched holes and what brand Jfets will be included in the kits.

It turns out that the topology of the B5 and the crossover are so similar
that it is trivial to stuff a single board for either way, just one more cap.

At the moment I have a prototype run that holds all the pots and
connectors. I am finishing it up next week for "field" testing.

There is artwork that is designed for the Galaxy 2u 230x230 chassis
and I believe that the store is arranging for the rears to be punched
with 7 holes, 6 for REAN RCA's and also a 2.5mm by 5.5mm barrel
connector for external supply.

Should be pretty sweet next month.

 

[Soundhappy]

Should be pretty sweet next month.

Yummy

 

[Telstar]

 

[MrTie]

@Nelson Pass

Will there be a 3 way kit available? I'm at an impasse building my system and waiting to see what the crossover kits look like before deciding between that or sticking to be a DSP solution.

 

[feds27]

Use two for tri-amping

 

[Telstar]

Maybe someone will mod it and make a 3-way version. I'm not that enthusiast to have the midrange passing two XOs.

 

[Zen Mod]

it's always passing two XOs

 

[Telstar]

it's always passing two XOs

Yes, I'm dumb
The XVR1 is the best XO I ever used, if this gets close in performance looks like I will go active again

 

[Nelson Pass]

Will there be a 3 way kit available? I'm at an impasse building my
system and waiting to see what the crossover kits look like before
deciding between that or sticking to be a DSP solution.

Yes, the rear panel I requested for the store has 8 RCA's.

Should be along shortly enough, designed to fit in the Galaxy 2u 230x230
or eleswhere.

 

[Dennis Hui]

Yippee!

 

[Telstar]

Yes, the rear panel I requested for the store has 8 RCA's.

Should be along shortly enough, designed to fit in the Galaxy 2u 230x230
or eleswhere.

 

[tyman63]

How will B4 differs from B5 and PAP-C1?

The B4 is a First Watt piece. There were 10 prototypes made
and floated around.

The initial design was strictly geared around full range drivers
used with woofers, both in open baffles, which included some
appropriate EQ circuits.

There is another design which is simply a crossover without the
EQ features.

Currently I'm working up the final artwork for a product to
appear in a couple months or so.

 

[Nelson Pass]

B5 and PAP both are 6 or 12 dB/oct biamp with Eq for the bottom and top.

B4 is 6,12,18,24 db biamp with no eq.

Both have level and frequency adjustments.

 

[Telstar]

B5 and PAP both are 6 or 12 dB/oct biamp with Eq for the bottom and top.

B4 is 6,12,18,24 db biamp with no eq.

B4 is what I need, I prefer high slope XOs when done active.

 

[Nelson Pass]

If my ambitious plans for crossovers are realized, then all of these
will be available through the store in kit form, helping to use up the
quarter million Jfets I have in stock.

 

[Telstar]

Awesome!

 

[tyman63]

B5 and PAP both are 6 or 12 dB/oct biamp with Eq for the bottom and top.



B4 is 6,12,18,24 db biamp with no eq.



Both have level and frequency adjustments.

Thanks for the quick response. The bottom eq in B5 is for BSC? In the case of B4, how does one compensates for the BSC? Sorry for the many questions as I am trying to understand how best to fit into my system. Maybe I should get both the B4 and B5 kit

 

[luxwinter]

Thanks for the quick response. The bottom eq in B5 is for BSC? In the case of B4, how does one compensates for the BSC? Sorry for the many questions as I am trying to understand how best to fit into my system. Maybe I should get both the B4 and B5 kit

The B5 has configurable BSC in the high pass section and non configurable low frequency boost for dipole woofers in the low frequency section. I suggest going to the First Watt website and looking up both the B4 and B5 under products. The manual for each crossover can be downloaded with lots of detail on what adjustments are available.