Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Multi-Way Conventional loudspeakers with crossovers

High Pass filter with 2.1?
High Pass filter with 2.1?
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
Reply
 
Thread Tools Search this Thread
Old 7th October 2018, 01:08 AM   #1
ddu is offline ddu
diyAudio Member
 
Join Date: Aug 2018
Default High Pass filter with 2.1?

Hi All,

So I think this must be obvious somewhere, but I'm having a hard time finding it.

So I built a pair of speakers that range from about 75Hz to 20kHz. They're a little shallow in the low end, so I'm thinking of adding a sub to them, and eventually 3 other speakers to make them 5.1. My impression is the best way to do this is to add a sub driver with a sub plate amp, and a receiver to power it all.

All the plate amp I have found have an adjustable low pass filter, but no high pass filter for the other speakers. Do most receivers have high pass filters already? Do I need a high pass filter on each speaker? That would get expensive. Or do I just run the speakers in their normal range, and adjust the sub low pass down to about 75Hz to meet their range?

Thanks!
  Reply With Quote
Old 7th October 2018, 01:30 AM   #2
Dave Bullet is offline Dave Bullet  New Zealand
diyAudio Member
 
Join Date: Jan 2002
Location: Wellington, New Zealand
Does your receiver have a setting for front speakers to be either small or large?
__________________
"Usual diyaudio train wreck of dubious drivers and just the crossover to sort out. Well, how are you on crossovers and modelling? Pretty green, I reckon" - system7 (Steve)
  Reply With Quote
Old 7th October 2018, 01:33 AM   #3
ddu is offline ddu
diyAudio Member
 
Join Date: Aug 2018
Quote:
Originally Posted by Dave Bullet View Post
Does your receiver have a setting for front speakers to be either small or large?
I don't have a receiver yet. I'm hesitant to buy anything until I have it all planned out. Right now my speakers are just powered by a little 2 way 30W amp board
  Reply With Quote
Old 7th October 2018, 01:59 AM   #4
chrisb is online now chrisb
diyAudio Member
 
Join Date: Aug 2002
Location: victoria BC
Most multi-channel home theatre receivers should provide all the bass management needed - i.e. independent selection of HP crossover frequencies for all of the active surround channels - even if used only in 2.1 mode initially - and the mono-summed output of LFE (sub) channel can obviate the need for LP filter on the outboard sub amp(s), so any decent power amp that you might just have kicking around would suffice. Indeed, several plate amps I’ve seen in the past have a LFE direct / LP filter bypass function when required signal processing is handled upstream. I’ve been using RCA Y- adaptor and variety of stereo power amps to drive a pair of small subs for at least half a dozen years now. Works just fine.

And of course, the other huge convenience feature of current HT receivers is the auto-calibration function. They’ll even stop to warn if any of the speakers are wired with reverse polarity - much easier to do with 7 + channels of DIY speakers than you might think. After the initial pass, they will normally suggest HP points for the mains/surrounds, which can be revised
__________________
you know I canít quit you, baby

Last edited by chrisb; 7th October 2018 at 02:04 AM.
  Reply With Quote
Old 7th October 2018, 02:16 AM   #5
ddu is offline ddu
diyAudio Member
 
Join Date: Aug 2018
Quote:
Originally Posted by chrisb View Post
Most multi-channel home theatre receivers should provide all the bass management needed - i.e. independent selection of HP crossover frequencies for all of the active surround channels - even if used only in 2.1 mode initially - and the mono-summed output of LFE (sub) channel can obviate the need for LP filter on the outboard sub amp(s), so any decent power amp that you might just have kicking around would suffice. Indeed, several plate amps Iíve seen in the past have a LFE direct / LP filter bypass function when required signal processing is handled upstream. Iíve been using RCA Y- adaptor and variety of stereo power amps to drive a pair of small subs for at least half a dozen years now. Works just fine.

And of course, the other huge convenience feature of current HT receivers is the auto-calibration function. Theyíll even stop to warn if any of the speakers are wired with reverse polarity - much easier to do with 7 + channels of DIY speakers than you might think. After the initial pass, they will normally suggest HP points for the mains/surrounds, which can be revised
So if I have a 280W sub driver, I could use a 300W plate amp, just turn the LP filter on it as high as it will go, then let the receiver do the rest?
  Reply With Quote
Old 7th October 2018, 06:36 AM   #6
rabbitz is offline rabbitz  Australia
diyAudio Member
 
rabbitz's Avatar
 
Join Date: Jul 2003
Location: Newcastle, Australia
In the receiver, set your speakers to small, turn the sub volume half way and the crossover all the way up. Then run the speaker setup via the supplied mic. It will set the sub at the correct (suggested) crossover and the bass from the other speaker channels are redirected to the LFE channel. You can play around with the results such as levels, xo and equaliser shaping.
__________________
No longer DIY active
  Reply With Quote
Old 8th October 2018, 12:46 AM   #7
chrisb is online now chrisb
diyAudio Member
 
Join Date: Aug 2002
Location: victoria BC
Or, as noted above, many “plate” amps will have either a separate LFE input, or bypass switch, which does effectively the same thing. It’s the auto-calibration function that takes as much as the guesswork out of the process as is possible. It’s been a while since I’ve run the full function on my Onkyo, but IIRC it wants you to set the subwoofer level to 75Db at the mic position before continuing to cycling the tone bursts to all possible channels, then repeating once it detects how many are actually connected.
Of course every make or perhaps even model year will likely have a different GUI / menu tree.

I recently price shopped for a smallish surround receiver for a family member and entry level mainstream name brands are starting at under $400 Cdn, which I personally consider a bargain, even after de-rating the “optimistic” power specs.

And FWIW, I’d consider the power handling rating of the sub driver to be interesting but almost irrelevant in the context of the likely operating levels of the overall system here.
__________________
you know I canít quit you, baby

Last edited by chrisb; 8th October 2018 at 01:10 AM.
  Reply With Quote
Old 9th October 2018, 05:38 PM   #8
ddu is offline ddu
diyAudio Member
 
Join Date: Aug 2018
Thanks all! Just bought the receiver and excited to finish the other speakers.
  Reply With Quote

Reply


High Pass filter with 2.1?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
The ultimate rumble filter - far more effective than just a high pass filter! monty78pig Analogue Source 64 17th February 2018 09:23 PM
Simplest 1st order high pass and low pass filter LeBurgh Analog Line Level 2 10th January 2017 10:46 AM
High pass filter vrusso123 Multi-Way 7 29th March 2014 04:56 AM
high gain 2nd order high pass active filter topology sreten Solid State 21 23rd March 2006 02:26 AM
Low/High Pass Filter fatpower17 Car Audio 1 28th June 2004 09:45 AM


New To Site? Need Help?

All times are GMT. The time now is 12:07 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki