ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1]   Go Down

Author Topic: A little surgery :)  (Read 3683 times)

John Fiorello

  • Full Member
  • ***
  • Offline Offline
  • Posts: 176
A little surgery :)
« on: October 05, 2009, 03:06:50 pm »

This is probably an easy question for most people here, but I have this older Peavey monitor that I want to use, but the old L-pad needs to go.


My question is, what do I need to do to bypass the L-pad?  There's only 3 wires going to the thing (it's kinda like defusing a bomb, I just need to know which wires to cut Smile ) and I'm assuming that I can just solder 2 of the three together and I'll have a direct feed to the speakers?   Or just go from jumper to jumper on the PC board and totally bypass everything?


Can anyone tell from the pictures which wires would need to be connected?  I put numbers by each wire to make it easier to refer to, and I labeled where the input and output jacks are.


Thanks!!!!


JF


index.php/fa/443/0/
Logged
Stop. Think. Speak.

Tom Young

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1174
Re: A little surgery :)
« Reply #1 on: October 06, 2009, 05:29:44 pm »

A few things about that photo:

1) It looks like the transformer on the bottom of the photo is the inductor (or one of 2 inductors) used for the crossover.

2) the circuit board at the top of the photo is the crossover. (see where it says "X-OVER" ?) Underneath that circuit board there will be miscellaneous parts such as capacitors, a smaller inductor and possibly a few large, square resistors.

More than likely the L-pad is being used as an attenuator for the HF horn. You do not want to bypass it. Take my word for it.

Use the L-pad to balance between the cone and the HF driver. Rotate it from full "off" (no HF's) until the speaker sounds "right".

This assumes everything is working correctly.

HTH
Logged
Tom Young, Church Sound section moderator
Electroacoustic Design Services
Oxford CT
Tel: 203.888.6217
Email: dbspl@earthlink.net
www.dbspl.com

Jordan Wolf

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 87
Re: A little surgery :)
« Reply #2 on: October 07, 2009, 07:09:23 pm »

Tom Young wrote on Tue, 06 October 2009 17:29

A few things about that photo:

1) It looks like the transformer on the bottom of the photo is the inductor (or one of 2 inductors) used for the crossover.

2) the circuit board at the top of the photo is the crossover. (see where it says "X-OVER" ?) Underneath that circuit board there will be miscellaneous parts such as capacitors, a smaller inductor and possibly a few large, square resistors.

More than likely the L-pad is being used as an attenuator for the HF horn. You do not want to bypass it. Take my word for it.

Use the L-pad to balance between the cone and the HF driver. Rotate it from full "off" (no HF's) until the speaker sounds "right".

This assumes everything is working correctly.

HTH


And if you don't want it to move, add some super glue to the edges of the knob to fix it in place.  It'll make future maintenance a little more difficult, though.
Logged
--Airport Circle Sound Reinforcement, LLC--

John Fiorello

  • Full Member
  • ***
  • Offline Offline
  • Posts: 176
Re: A little surgery :)
« Reply #3 on: October 08, 2009, 12:34:42 pm »

Tom Young wrote on Tue, 06 October 2009 17:29

A few things about that photo:

1) It looks like the transformer on the bottom of the photo is the inductor (or one of 2 inductors) used for the crossover.



Yep, Tom you're right

Tom Young wrote on Tue, 06 October 2009 17:29


2) the circuit board at the top of the photo is the crossover. (see where it says "X-OVER" ?) Underneath that circuit board there will be miscellaneous parts such as capacitors, a smaller inductor and possibly a few large, square resistors.



Yep, right again


Tom Young wrote on Tue, 06 October 2009 17:29


More than likely the L-pad is being used as an attenuator for the HF horn. You do not want to bypass it. Take my word for it.


I totally would agree with you, Tom, if it was only attenuating the HF, I wouldn't want to bypass it because I wouldn't be able to balance the two drivers depending on the application.


In this case though, the pad is attenuating both speakers.  But since it's an old monitor, I can't find any info from peavey or otherwise with a wiring diagram to verify that.  It's a 112hs.



That being said, is there a way to bypass the pad?  Or would I end up having to bypass the x-over, rendering the monitor useless?


Does that make sense?  Thanks for your input!



JF

Logged
Stop. Think. Speak.

Benamin John Brunskill

  • Newbie
  • *
  • Offline Offline
  • Posts: 42
Re: A little surgery :)
« Reply #4 on: October 08, 2009, 03:32:54 pm »

I can't view the your picture at work, but here's a diagram of a normal L-Pad wiring:

http://www.pachitalk.com/L-Pad.jpg

Hope that helps,
Ben.
Logged

John Fiorello

  • Full Member
  • ***
  • Offline Offline
  • Posts: 176
Re: A little surgery :)
« Reply #5 on: October 09, 2009, 12:17:43 pm »

Thanks Ben,


So, if I short out pin 2 and 3, it will bypass the pad (according to your drawing) and pin 1 can go directly to the speaker (or in my case the x-over.



I'll give it a try and see what happens Smile



Thanks!


JF
Logged
Stop. Think. Speak.

ProSoundWeb Community

Re: A little surgery :)
« Reply #5 on: October 09, 2009, 12:17:43 pm »


Pages: [1]   Go Up
 



Page created in 0.068 seconds with 24 queries.