quality of high pass section of a plate amp

[pforeman]

OK, I've built my H frames, solid maple tops & bottoms, maple plywood sides.
I've ordered the dayton audio plate amplifers (one 250 W for each channel.
I haven't ordered the crossover caps for my full ranger yet.
I was wondering what people think of the quality of the sound of the crossover thats in the plate amplifier (high pass section that is)
Thanks,
Paul

[planet10]

Most of them are somewhat lacking.

dave

[ashok]

Considering that the typical plate amp is a mass market product one couldn't expect it to be populated with expensive/exotic parts.
However if the conditions are right you could probably upgrade some sections to 'improve' the sound of the high pass section.
I have seen some plate amps using SIL small signal chips and that will not be suitable for a 'high grade' DIP chip replacement.
The option might be to copy the high pass section and input stage and implement it with good DIP 'audio grade' chips and PP film caps ( if any ) and BG elco's and put it on a small pcb and mount it piggyback on the main board.
Not simple ,but doable I think.

[pforeman]

Thanks, but it would be simpler, I think to just do a passive second order for the high pass, I just havent ordered them yet.
Paul

[planet10]

Originally posted by pforeman
Thanks, but it would be simpler, I think to just do a passive second order for the high pass, I just havent ordered them yet.
Paul

Most of the time to do 2nd order PLLXO requires a HF amp with sufficiently high input impedance.

A passive XO after the amps is a nightmare because of the rising impedance due to resonance (not to mention the cost)

What HF speakers are you wanting to XO and what amp do you plan on driving them with?

dave

[pforeman]

This is a amp/speaker build. I'm next going to build the tubelab simple se . Because it will probably mainly be used by my daughter (high spl's) I wanted a bigger full ranger, so I've ordered, but have not yet received the 10 inch audio nirvana.
The bass will be made by the H frame powered by the plate amp.
I've also considered a crossover like my vandersteen subwoofer (acoustat 2+2 with new york audio labs moscode).
with the vandersteen, the high pass to main speaker is crossed over with a input cap on the amp. This, of course only gives a 6 dB / octave high pass section.
But if I set it at 400 Hz (as in MJK's recommendation ((12 dB / octave)) with a 10 inch full range, I think it still might work, if not I can remove the input cap at that small value it won't be too expensive. Then I'd do a conventional speaker crossover.
Thanks,
Paul

[planet10]

Originally posted by pforeman
with the vandersteen, the high pass to main speaker is crossed over with a input cap on the amp.

The simpliest of PLLXOs.

dave