Active crossover suggestion with F5

[anilva]

I am planning to use a Jfet BoZ as a preamp and F5s as my Power amps. I need suggestions to build a 2-way active crossover between JBoZ and F5 for HF and LF. My speakers are Altec 416A in a Onken cabinet and a Altec 808 HF in a 811b horn. Both at 8 ohms.

Cheers.

[Bksabath]

I will be watching this as I am planning on By amp eventualy.

I don't know your speakers so can't comment on the design.

Be handy to know more about the cross over you have now.
I assume is a 6 dB job and maybe going active is not ideal.

I had a brief look at Papa stuff as he has a cross over out on the market it would be a good idea to start there.

I see you mention a Behringer Digital Xover on your list of goodies that and a program like True RTA (there is beter and free stuff out there) may help to decide which way to go.

You can also gogle Bensen Buteworth Salemkey a couple of op amps and few passive can do the job the question is would you like how they sound?

[Zen Mod]

go search for "cottage" - here in Pass Forum

diyAudio - Search Results

[anilva]

Originally Posted by Bksabath

I will be watching this as I am planning on By amp eventualy.

I don't know your speakers so can't comment on the design.

Be handy to know more about the cross over you have now.
I assume is a 6 dB job and maybe going active is not ideal.

I had a brief look at Papa stuff as he has a cross over out on the market it would be a good idea to start there.

I see you mention a Behringer Digital Xover on your list of goodies that and a program like True RTA (there is beter and free stuff out there) may help to decide which way to go.

You can also gogle Bensen Buteworth Salemkey a couple of op amps and few passive can do the job the question is would you like how they sound?

Thanks. The Altecs are high efficiency vintage speakers.

I do have a Behringer digital xover, which i use today and am happy with that. But it is definitely not the minimalist, super high quality "pass" like design.

I need something far simpler but high quality crossover to make.

Yes, i have heard of B5, and from what i have read would have been the right crossover to add, but the design in not published by Papa and i cannot afford the commercial variant as of now.

Cheers.

[anilva]

Originally Posted by Zen Mod

go search for "cottage" - here in Pass Forum

diyAudio - Search Results

Ok will do cottage hunting...

[BobEllis]

You could try a passive line level xo into a B1 or B3 clone. Just a couple RC and a buffer. You may need some gain.

You can also wrap a Sallen Key filter around a jfet Source follower if the passive 2nd order is too lossy.

Are you able to get decent response without significant eq or delay? If not you may need to use an opamp based solution. If you need the bass boost or dipole eq there are buffered passive means, but for simpletons like me an opamp makes life easier.

[Bksabath]

anilva
Did you mannage to gogle up true RTA and such.

That program + your cross over should give you same straigt answers on what you need to start.

Still I think Bob Ellis got it right Just RC and buffer is the way I would go.

At least till Papa give us is blessing to copy is stuff.

[anilva]

Originally Posted by Bksabath

anilva
Did you mannage to gogle up true RTA and such.

That program + your cross over should give you same straigt answers on what you need to start.

Still I think Bob Ellis got it right Just RC and buffer is the way I would go.

At least till Papa give us is blessing to copy is stuff.

Behringer is nowhere close to the kind of sound we are used to from F5. It has hiss, turn on transients and missing detail. This is not to say that Behringer is a write off, but compared to the quality of Pass stuff, the differences magnify.

The right thing to mate a F5 is to connect up to another pass design, or close to that.

Cheers.

[WithTarragon]

Originally Posted by anilva

Behringer is nowhere close to the kind of sound we are used to from F5. It has hiss, turn on transients and missing detail. This is not to say that Behringer is a write off, but compared to the quality of Pass stuff, the differences magnify.

The right thing to mate a F5 is to connect up to another pass design, or close to that.

Cheers.

Actually, this is a perfect DIY project.

A Behringer DCX only costs about $300. Go ahead an snip out the analog output section and take the output of the DAC and directly run it into a buffer, or a fancy pre-amp, transfomer, or into a resistor pot (you will need DC blocking caps and you may want a simple anti-imaging filter).

Then you are only relying on the Behringer DAC (the AKM is a decent DAC, better than most) and the Behringer DSP (the SHARC is better than most). The clock and power supply can always be upgraded, but they are not the weak links in the system.

It has very good functionality, 2 (or 3 ) inputs and 6 outputs, with a variety of filter, delays etc.

Yes, the reliability is not great, but this will be in a staionary configuration. I will repeat, it is only $300. Once you have bypassed the analog out sections, I am not sure the $3000 units sound that much better.

[michal]

I am using miniDSP with F5, and the DSP deteriorates quality a lot (IMO). With a cheap active crossover from my car I can't localize speakers, with miniDSP I can. I am not saying miniDSP is bad, it's still a very good product, but not a good match for F5.

I have no experience with DCX, but probably going full analog after your source is better for F5.

I've seen a comparison of miniDSP to DCX claiming miniDSP being at par or better than DCX.

anilva, did you try using your Behringer Digital Xover to figure out xover points and slopes, and then replicate with analog circuit?