Synth-DIY Yahoo! Groups Archives

Thread

Assistance with schematic and pcb- 3way active crossover

2006-12-03 by david.mcauliffe@propadog.com

Hi,

I'm looking for some help with a PCB, and its schematic. I'm not
feeling very confident at the moment.

It comes from a stereo 3-way active crossover, which is twice as many
channels as I need. This send the signal to three amplifiers, not
three speakers. I'm also looking at a couple of little changes as it's
going to be used on an instrument rather than an audio system- 1/4
jacks instead of RCA, that sort of thing.

I've managed to get the schematic for one channel, and the power
supply, and an image of the stereo PCB. I'm looking for some help
putting the channel and the power supply together, and then onto a PCB.

It uses three quad op-amp TL074s, and I was also hoping to get some
advice on whether there is anything newer and quiter. Or maybe even
changing this to six quieter op amps (the chip number escapes me right
at this moment - I've got 5534s or similar echoing in my mind??? My
notes are elsewhere!)

I'm not willing to post the info I've got openly yet. While the design
was originally published in a magazine and the PCB is available on
their web site, I'm not too sure about the copyright status and
throwing it open to the group.

If anyone feels like they want to and can help, can you drop me a line
on this email.

Hoping to hear from someone soon,

Cheers,

David.

Assistance with schematic and pcb- 3way active crossover

2006-12-03 by david_mcauliffe

(Sorry if this is a dupe- I didn't see it show up)

Hi,

I'm looking for some help with a PCB, and its schematic. I'm not
feeling very confident at the moment.

It comes from a stereo 3-way active crossover, which is twice as many
channels as I need. This send the signal to three amplifiers, not
three speakers. I'm also looking at a couple of little changes as
it's going to be used on an instrument rather than an audio system- 1/
4" jacks instead of RCA, that sort of thing.

I've managed to get the schematic for one channel, and the power
supply, and an image of the stereo PCB. I'm looking for some help
putting the channel and the power supply together, and then onto a
PCB.

It uses three quad op-amp TL074s, and I was also hoping to get some
advice on whether there is anything newer and quiter. Or maybe even
changing this to six quieter op amps (the chip number escapes me
right at this moment - I've got 5534s or similar echoing in my
mind??? My notes are elsewhere!)

I'm not willing to post the info I've got openly yet. While the
design was originally published in a magazine and the PCB is
available on their web site, I'm not too sure about the copyright
status and throwing it open to the group.

If anyone feels like they want to and can help, can you drop me a
line on this email.

Hoping to hear from someone soon,

Cheers,

David.

Re: [Homebrew_PCBs] Assistance with schematic and pcb- 3way active crossover

2006-12-03 by \M

I am fiddling with a 2-way active filter with options like phaseshift on the LP-filter and adjustable Q.
I am using standard dual OPAMPs from BB- OPA2134. Not top of the top but enough good to be used in audio equipment.

The idea is to make one PCB with the filter and keep the PSU separated - different chassis to keep noise and hum down.

/M

----- Original Message -----

Show quoted textHide quoted text

From: david.mcauliffe@...
To: Homebrew_PCBs@yahoogroups.com
Sent: Sunday, December 03, 2006 10:47 AM
Subject: [Homebrew_PCBs] Assistance with schematic and pcb- 3way active crossover

Hi,

I'm looking for some help with a PCB, and its schematic. I'm not
feeling very confident at the moment.

It comes from a stereo 3-way active crossover, which is twice as many
channels as I need. This send the signal to three amplifiers, not
three speakers. I'm also looking at a couple of little changes as it's
going to be used on an instrument rather than an audio system- 1/4
jacks instead of RCA, that sort of thing.

I've managed to get the schematic for one channel, and the power
supply, and an image of the stereo PCB. I'm looking for some help
putting the channel and the power supply together, and then onto a PCB.

It uses three quad op-amp TL074s, and I was also hoping to get some
advice on whether there is anything newer and quiter. Or maybe even
changing this to six quieter op amps (the chip number escapes me right
at this moment - I've got 5534s or similar echoing in my mind??? My
notes are elsewhere!)

I'm not willing to post the info I've got openly yet. While the design
was originally published in a magazine and the PCB is available on
their web site, I'm not too sure about the copyright status and
throwing it open to the group.

If anyone feels like they want to and can help, can you drop me a line
on this email.

Hoping to hear from someone soon,

Cheers,

David.

[Non-text portions of this message have been removed]

Re: [Homebrew_PCBs] Assistance with schematic and pcb- 3way active crossover

2006-12-03 by david.mcauliffe@propadog.com

Thanks for that.

What I'm really looking for is some help going over a circuit that has
been hacked from stereo back to mono and making sure that all the
wires connect up (so to speak), on schematic and PCB.

Any takers?

Quoting "\\M" <yahell@...>:

Show quoted textHide quoted text

>
> I am fiddling with a 2-way active filter with options like
> phaseshift on the LP-filter and adjustable Q.
> I am using standard dual OPAMPs from BB- OPA2134. Not top of the
> top but enough good to be used in audio equipment.
>
> The idea is to make one PCB with the filter and keep the PSU
> separated - different chassis to keep noise and hum down.
>
>
> /M
>
> ----- Original Message -----
> From: david.mcauliffe@...
> To: Homebrew_PCBs@yahoogroups.com
> Sent: Sunday, December 03, 2006 10:47 AM
> Subject: [Homebrew_PCBs] Assistance with schematic and pcb- 3way
> active crossover
>
>
> Hi,
>
> I'm looking for some help with a PCB, and its schematic. I'm not
> feeling very confident at the moment.
>
> It comes from a stereo 3-way active crossover, which is twice as many
> channels as I need. This send the signal to three amplifiers, not
> three speakers. I'm also looking at a couple of little changes as it's
> going to be used on an instrument rather than an audio system- 1/4
> jacks instead of RCA, that sort of thing.
>
> I've managed to get the schematic for one channel, and the power
> supply, and an image of the stereo PCB. I'm looking for some help
> putting the channel and the power supply together, and then onto a PCB.
>
> It uses three quad op-amp TL074s, and I was also hoping to get some
> advice on whether there is anything newer and quiter. Or maybe even
> changing this to six quieter op amps (the chip number escapes me right
> at this moment - I've got 5534s or similar echoing in my mind??? My
> notes are elsewhere!)
>
> I'm not willing to post the info I've got openly yet. While the design
> was originally published in a magazine and the PCB is available on
> their web site, I'm not too sure about the copyright status and
> throwing it open to the group.
>
> If anyone feels like they want to and can help, can you drop me a line
> on this email.
>
> Hoping to hear from someone soon,
>
> Cheers,
>
> David.
>
>
>
>
> [Non-text portions of this message have been removed]
>
>

Re: Assistance with schematic and pcb- 3way active crossover

2006-12-04 by jr_dakota

Since most active crossovers are unity gain filters with a fairly high
impedance and input drive level, the TL07x opamps should work just
fine, better than a low impedance bi-polar input opamp like the NE553x
series and as well as a 'boutique' high dollar FET opamp that probably
won't gain you much, if anything, especially at a cost vs performance
ratio

JR

--- In Homebrew_PCBs@yahoogroups.com, "david_mcauliffe"
<david.mcauliffe@...> wrote:

Show quoted textHide quoted text

>
> (Sorry if this is a dupe- I didn't see it show up)
>
> Hi,
>
> I'm looking for some help with a PCB, and its schematic. I'm not
> feeling very confident at the moment.
>
> It comes from a stereo 3-way active crossover, which is twice as many
> channels as I need. This send the signal to three amplifiers, not
> three speakers. I'm also looking at a couple of little changes as
> it's going to be used on an instrument rather than an audio system- 1/
> 4" jacks instead of RCA, that sort of thing.
>
> I've managed to get the schematic for one channel, and the power
> supply, and an image of the stereo PCB. I'm looking for some help
> putting the channel and the power supply together, and then onto a
> PCB.
>
> It uses three quad op-amp TL074s, and I was also hoping to get some
> advice on whether there is anything newer and quiter. Or maybe even
> changing this to six quieter op amps (the chip number escapes me
> right at this moment - I've got 5534s or similar echoing in my
> mind??? My notes are elsewhere!)
>
> I'm not willing to post the info I've got openly yet. While the
> design was originally published in a magazine and the PCB is
> available on their web site, I'm not too sure about the copyright
> status and throwing it open to the group.
>
> If anyone feels like they want to and can help, can you drop me a
> line on this email.
>
> Hoping to hear from someone soon,
>
> Cheers,
>
> David.
>