Tips for woofers/mics/amplification and impedance - diyAudio
Go Back   Home > Forums > Design & Build > Construction Tips

Construction Tips Construction techniques and tips

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 2009, 02:50 PM   #1
diyAudio Member
 
Join Date: Nov 2009
Default Tips for woofers/mics/amplification and impedance

Hallo everyone. I'm currently working on a couple of projects and i've
got several doubts regarding amplification and impedance. long story short:
i have a DYH-810 8'' woofer and i'm trying to understand what kind of amp should i connect, and that is where understanding impedance really comes into play. Since the woofer is 4OHM, i suppose i should connect an amp with an output impedance which is LOWER than that, am i correct? this statement comes because i used a small tube amp which i have, which has an output impedance of 51OHM and the efficiency of the woofer was *really* poor. also: i've got a number of contact mics(piezo discs) and for another project i have to use one as a mic and one in output, as a sortof speaker. so question is: what kind of amplification should i use for the "output contact mic" and for the "input contact mic", so to speak? should i always follow the low-to-high impedance combination? thanks in advance guys
  Reply With Quote
Old 18th November 2009, 04:48 PM   #2
diyAudio Member
 
thermal runaway's Avatar
 
Join Date: Mar 2007
Location: West Mids , UK
Regarding the speaker , as long as the spec of the amp states that the impedance range is from 4 ohms you won't have a problem. Valve amps are different , they have an output transformer and it's important the speaker connected matches the output impedance of the transformer. Some valve amp transformers have a number of impedance taps so that the speaker can be matched.

Can't help you with the mics , never did much with them.
  Reply With Quote
Old 20th November 2009, 12:09 AM   #3
diyAudio Member
 
Join Date: Feb 2002
Location: Western Sydney
A piezo mic will need a high input impedance, of the order of 1 megohm.
some info on using them as out devices:
Lynn and Steve's Piezo page
__________________
Impedance varies with frequency, use impedance plots of your drivers and make crossover calculations using the actual impedance of the driver at the crossover frequency
  Reply With Quote
Old 20th November 2009, 07:42 AM   #4
Enzo is offline Enzo  United States
diyAudio Member
 
Join Date: Sep 2004
Location: Lansing, Michigan
A 51 ohm output? I have never seen that. Printed on it, or did you determine that somehow? Keep in mind resistance and impeance are not the same.
  Reply With Quote
Old 20th November 2009, 10:58 AM   #5
diyAudio Member
 
Join Date: Nov 2009
PreSonus

go in "tech specs" and it shows it, assuming that i understand the thing correctly...i'm also using this tube pre for piezos, sometimes, and it doesnt work too bad.
  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
Elation mics bernification Everything Else 0 23rd July 2007 11:24 AM
Impedance and current-source amplification 454Casull Multi-Way 77 24th January 2007 01:27 AM
MXL 770 mics - any mods? Wavebourn Instruments and Amps 7 27th October 2006 10:16 PM
Measurement mics bombardon73 Multi-Way 22 28th November 2004 01:56 PM
Calibrating Mics. Link pinkmouse Multi-Way 0 29th January 2003 08:10 AM


New To Site? Need Help?

All times are GMT. The time now is 01:36 AM.


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