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Assistance with schematic and pcb- 3way active crossover

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
Show quoted textHide quoted text
  ----- 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: [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.
>

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