How can I connect my subwoofer?? - diyAudio
Go Back   Home > Forums > Loudspeakers > Subwoofers

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 18th November 2005, 12:20 PM   #1
kayjayw is offline kayjayw  Scotland
diyAudio Member
 
Join Date: May 2004
Location: Athens, Greece
Default How can I connect my subwoofer??

Hi! I wonder if anyone can help me with a small speaker dilemma… I have been given a subwoofer with cab (Adire 12” – don’t know specs as I can’t contact the guy who gave it to me!). I’d like to hook it up to my system (NAD 3020 amp connected to Humble Homemade HiFi Tempo speakers each with Seas H831 tweeter & Vifa PL18WO-09 midwoofer) to increase the bass. The problem is how to connect the subwoofer. My amp only has one set of speaker outputs. Is there a splitter device that can allow the subwoofer to be connected to these – and will there be an impedance conflict or a volume differential? Alternatively, someone suggested connecting the subwoofer via a dedicated amp to the tape out (pricey?). I am obviously no genius when it comes to these matters so any help appreciated!
Regards, Kevin
  Reply With Quote
Old 18th November 2005, 12:37 PM   #2
simon5 is offline simon5  Canada
diyAudio Member
 
Join Date: Nov 2004
Location: Québec, Québec
It's probably a Shiva if you paid a low price for it. It's a dual 8 ohms voicecoil, probably wired in parallel to make a 4 ohms load. I'm quite sure your NAD amplifier wouldn't like a 4 ohms load in parallel of what you already have, but I could be wrong.

You should buy a separate plate subwoofer amplifier. To power a Shiva, I would shop at Rythmik Audio for a 250W (109$) or 350W (149$) amplifier. I used a 250W on the one I built and the owner, besides hitting the protection circuit often (115+ dB measured with a ratshack using a correction sheet), she loves it. I guess if I went with the 350W version, she would burn the poor woofer, she's a heavy user hehe! If yours is in a smaller box, then you could use the 350W version without problems, but it is worth it? You'll gain about 2 dB in output, you decide.

You could also get the audiophile version, you decide if it's worth it also.

Link:
http://www.rythmikaudio.com/nonservo_product.htm

There you can buy it too if you don't want to order directly from them (price is slightly higher):
http://www.acoustic-visions.com/~aco...rs/index.shtml

EDIT: Just saw your were in Greece, I don't know if they ship there or if there's great local alternatives, you might want to look around. Anyway to connect the subwoofer with your NAD, you'll need to build a nice lowpass x-over anyway if you don't go the separate plate amplifier route...
__________________
DIYaudio for President !
  Reply With Quote
Old 18th November 2005, 01:20 PM   #3
DorinD is offline DorinD  Romania
diyAudio Member
 
DorinD's Avatar
 
Join Date: Jan 2005
Location: Bucharest
Why don't use something like this:
http://www.visaton.com/english/bildg..._bweiche1.html
So, for an uniq sub you can make a "mechanicaly" L and R channel sum using both voicecoils and without lowering the impedance seen by your oldy NAD.
  Reply With Quote
Old 18th November 2005, 01:38 PM   #4
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
But that will lower the impedance seen by the amp, not to mention that the passive filter will offer pretty poor performance and no way to match level between the sub and main speakers.

IMO passive subs should not be considered, especially with decent main speakers like what he has.
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more.
  Reply With Quote
Old 18th November 2005, 01:53 PM   #5
DorinD is offline DorinD  Romania
diyAudio Member
 
DorinD's Avatar
 
Join Date: Jan 2005
Location: Bucharest
Quote:
Originally posted by richie00boy
But that will lower the impedance seen by the amp, not to mention that the passive filter will offer pretty poor performance and no way to match level between the sub and main speakers.
He could use the same sub crossover to cross-high the mains and get them sattelites (by taking signal parallel with the inductors). In this case impedance will never being lowered.
Using a passive sub is a challenge but is worth trying if the mains a not so sensitive. I use such setup with horn mains (sensitivity about 100dB) crossed @80Hz but woofers were 2x4 ohm in an unstuffed strait TL of 2.5 meters.
  Reply With Quote
Old 18th November 2005, 06:37 PM   #6
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
The problem is twofold:

1. Lack of damping at the filter -3dB point, making the bass flabby.

2. The impedance of the main speakers and possibly also the sub will be all over the place through the crossover, so the response will be all over the place.

Try it, but it's certainly not high fidelity.
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more.
  Reply With Quote
Old 21st November 2005, 07:24 AM   #7
kayjayw is offline kayjayw  Scotland
diyAudio Member
 
Join Date: May 2004
Location: Athens, Greece
Thanks everyone! I got a bit lost with the technical advice, but what I gleaned was that it seems preferable to buy a separate plate amp. The driver I have must be a Shiva as the cabinet design is a Shiva one. The point is to have an element of HiFi - not just a botched together setup. Simon5 mentioned building a low pass crossover. Where can I get a design drawing of one of those? Where will the subwoofer amp actually connect with my main amp?
Regards
  Reply With Quote
Old 21st November 2005, 08:43 AM   #8
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

get a decent plate amplifier - it will include the low pass crossover.

For a NAD3020 you can connect the Sub to either the speaker outputs,
which will not be additionally loaded, or split the pre-amp out connection
to provide output to the sub and the 3020 power amplifier section.

/sreten.
  Reply With Quote
Old 21st November 2005, 09:37 AM   #9
sumacSK is offline sumacSK  Slovakia
diyAudio Member
 
Join Date: Jun 2004
Location: Prague
Send a message via ICQ to sumacSK
Hi sreten,

What do you mean with " split the pre-amp out connection" - just run 2 wires from where should be only one? I'm really interested in thist because I have the same problem.

Thanks Martin
  Reply With Quote
Old 21st November 2005, 11:38 AM   #10
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Quote:
Originally posted by sumacSK
Hi sreten,
What do you mean with " split the pre-amp out connection"
- just run 2 wires from where should be only one? I'm really
interested in thist because I have the same problem.
Thanks Martin
Yes, exactly that.
Though I will note that doing this on my Audiolab 8000A turned out
not to be a good idea as the extra loading (presumably the capacitance
of the long stereo sub cable) degraded the treble performance too much.

/sreten.
  Reply With Quote

Reply


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
How connect the Gnd. samsagaz Chip Amps 50 19th May 2008 05:09 AM
how to connect a non powered subwoofer to a stereo system without a subwoofer output JSD777 Multi-Way 4 20th September 2005 03:19 PM
how connect to subwoofer? alejo Subwoofers 8 29th November 2004 12:06 PM
HELP to connect a subwoofer cristiano Subwoofers 2 16th April 2004 02:14 PM
Best way to connect a sub to a GC? sounder Chip Amps 5 13th October 2003 04:40 AM


New To Site? Need Help?

All times are GMT. The time now is 08:55 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2