Crossover between pre and power amp for sub - diyAudio
Go Back   Home > Forums > Source & Line > Analog Line Level
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Analog Line Level Preamplifiers , Passive Pre-amps, Crossovers, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 3rd January 2013, 12:16 AM   #1
diyAudio Member
Join Date: Jan 2013
Default Crossover between pre and power amp for sub

I'm trying to figure out what exactly I should be doing in this situation. I am using a NwAVguy Objective2 headphone amp as my pre-amp, and my NAD reciever as a power-amp. I have some bookshelf speakers at the moment but will be getting some new ones soon (if speaker impedance matters?). I also have an active sub that has it's own adjustable crossover (up to 80Hz). I am looking for something that I can put after my pre-amp that will send a signal to my sub, as well as provide a cut-off so that the bookshelf speakers aren't trying to drive low frequencies that my sub can do (partially to reduce stress to the speakers). I presume I should be building a passive crossover for this purpose?
  Reply With Quote
Old 3rd January 2013, 12:50 AM   #2
diyAudio Member
Join Date: Apr 2012
i suppose something like this would work if the subwoofer is a DVC sub Cerwin Vega Sub Woofer 200 watt Crossover
  Reply With Quote
Old 3rd January 2013, 04:27 AM   #3
diyAudio Member
Join Date: Jan 2013
Thanks for the reply. I don't believe it's a DVC sub (as it only has a single line input and 2 wires leading to the driver itself?)
  Reply With Quote
Old 3rd January 2013, 06:35 AM   #4
diyAudio Member
Join Date: Apr 2012
yeah thats not a DVC then if there is only 1 set of hookups on the driver. not sure how else to go about it...but its very late here...if i think of something ill post again
  Reply With Quote
Old 3rd January 2013, 08:08 PM   #5
diyAudio Member
Join Date: Apr 2012
Not sure what else we can do (that I can think of).....does your subwoofer have its own amp or is it powered by your receiver? If it isn't a powered sub it might be easiest to get a plate amp for it and run it off of your LFE output of your receiver. That would eliminate it from the chain wof your bookshelf speakers and solve the issue (if I'm understanding your setup correctly)

oh and then a simple passive crossover could eliminate the lower frequencies from your bookshelf speakers
  Reply With Quote
Old 3rd January 2013, 08:24 PM   #6
diyAudio Member
sofaspud's Avatar
Join Date: Nov 2005
Location: San Antonio
I think this recent thread starter sought the exact same solution:
x'over for a sub?
It is error only, and not truth, that shrinks from enquiry. - Thomas Paine
  Reply With Quote
Old 3rd January 2013, 10:57 PM   #7
diyAudio Member
Join Date: Jan 2013
Pantstain, my sub is active with it's own filter and my reciever is being used soley as a power-amp. I think the thread sofaspud linked was quite relevant however it seems that the OP of that thread had a DVC sub? I think I need a way to get a mono(?) sub line out of the stereo line out of my pre-amp. Then simply a passive filter/crossover to cut out the low frequencies going into my speakers? Thanks for the consideration and replies.
  Reply With Quote
Old 4th January 2013, 06:55 PM   #8
diyAudio Member
Join Date: Apr 2012
Yeah I'm not really sure.... but I did see a thing the other day surfin the web who knows where...but it was a module that converted 2 signals (from a stereo amp) and allowed them to be bridged (even if the amp wasn't bridgeable). But as to where I found it or how it would affect the audio signal I'm not sure
  Reply With Quote
Old 4th January 2013, 07:33 PM   #9
sreten is offline sreten  United Kingdom
diyAudio Member RIP
Join Date: Nov 2003
Location: Brighton UK

One (or two) method(s) :

Reduce the power amplifiers input coupling caps to high pass the satellites.
(You can use external series caps wired into the phono plugs.)

If the preamp can drive the cables to the sub simply split the output cables.

(If it can't - my pre-amp lost too much quality driving the long sub cables :
From the power amplifier speaker outputs design attenuators for the
subwoofer line inputs, include in the attenuators a reverse low pass
passive filter that corrects the the roll-off off applied to the sats,
you can't do this to DC, so pick a low frequency like 10Hz.)

rgds, sreten.
  Reply With Quote
Old 5th January 2013, 10:19 AM   #10
diyAudio Member
Join Date: Jan 2013
Thanks for the replies. srten, I am not sure how this would work as my sub has a single line in, not stereo? If I use input caps for a high pass filter into the power amp for the speakers, then I could [somehow?] design something to get the stereo line and feed it into a single line for the sub and let the sub controll what it's crossover point is (it has adjustment on it's own amp).
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
power suply for Pre & Phono Use tube 6BM8 dia thien thai Tubes / Valves 5 23rd November 2011 04:17 PM
FS: 1626 Tube Amp, Van Alstine pre, tubes, crossover. xecluded Swap Meet 1 30th April 2009 07:27 AM
Seperate power supply for pre-amp section in integrated amp? KevinLee Solid State 8 2nd February 2008 10:20 PM
WIll an X-PSU v1 power an SI T-amp &/or TC754 pre-amp? gnostic19 Class D 7 3rd August 2007 01:26 AM
Using power supply to power pre-amp? preiter Chip Amps 4 11th May 2006 12:52 PM

New To Site? Need Help?

All times are GMT. The time now is 08:24 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2