100v amplifier on 70v speakers - AVS | Home Theater Discussions And Reviews
Baselworld is only a few weeks away. Getting the latest news is easy, Click Here for info on how to join the Watchuseek.com newsletter list. Follow our team for updates featuring event coverage, new product unveilings, watch industry news & more!


Forum Jump: 
 
Thread Tools
Old 05-15-2013, 02:48 AM - Thread Starter
Newbie
 
jeroen@bmb's Avatar
 
Join Date: Apr 2012
Location: The Netherlands
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Dear all,

I`m new to 70/100v speaker systems and need some help.

Is it safe to connect a 100v amplifier to 70v speakers?

jeroen@bmb is offline  
Sponsored Links
Advertisement
 
Old 05-15-2013, 01:35 PM
Member
 
ZeGhostbear's Avatar
 
Join Date: Dec 2010
Location: Toronto, Canada
Posts: 91
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Have you contacted terra directly about this issue?

Current commercial audio Crown amplifiers support both voltages. Which amplifier are you using?
ZeGhostbear is offline  
Old 05-16-2013, 02:35 AM - Thread Starter
Newbie
 
jeroen@bmb's Avatar
 
Join Date: Apr 2012
Location: The Netherlands
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hi,

Yes I contacted Terra, they think adding a 70v amplifier to 100V speakers systems is no problem but a 100v amplifier on a 70v speaker system might cause trouble.
Their respond seem to me that they are not realy sure thats why I post here.

At this moment I dont have an install so there is no amplifier specified yet, but I just want to know for the future incase an install allready has a 100v amplifier.

Long time ago at school I learned it didnt matter as long as the total wattage of the speaker line dindnt pass the wattage output of the amplifier it should be good to go.
But that was a long time ago and I`m not realy sure.

Thanks for helping in advance!
jeroen@bmb is offline  
Old 05-16-2013, 06:31 AM
AVS Special Member
 
DonH50's Avatar
 
Join Date: Feb 2010
Location: Monument CO
Posts: 6,737
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 442 Post(s)
Liked: 387
It will depend upon how much design margin the 70 V speakers have. The 70 V and 100 V ratings typically refer to the max voltage, so a 70 V speaker must be able to handle 100 V peaks without damage. Meaning transformers and drivers...

"After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
DonH50 is online now  
Old 05-16-2013, 10:37 AM
 
BobL's Avatar
 
Join Date: Nov 2001
Posts: 3,797
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 54

You can use it as the transformers work at different voltages.  The rated wattage is ~doubled, so if you set the speaker to 16 watts you need to calculate for 32 watts if using multiple speakers and calculating to stay within your wattage limit of the amplifier.  Also, using a 70V speaker with a 100V amplifier will half the rated low frequency extension.  So if the speaker is rated 70hz it will now be only able to go down to ~140hz before distorting.  In general you are better off matching it if possible, but the speaker will work.

 

Another option would be to set the speaker to 8 ohm and use step down transformer for 100V.

BobL is offline  
Old 05-16-2013, 11:28 PM - Thread Starter
Newbie
 
jeroen@bmb's Avatar
 
Join Date: Apr 2012
Location: The Netherlands
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by BobL View Post

You can use it as the transformers work at different voltages.  The rated wattage is ~doubled, so if you set the speaker to 16 watts you need to calculate for 32 watts if using multiple speakers and calculating to stay within your wattage limit of the amplifier.  Also, using a 70V speaker with a 100V amplifier will half the rated low frequency extension.  So if the speaker is rated 70hz it will now be only able to go down to ~140hz before distorting.  In general you are better off matching it if possible, but the speaker will work.

Another option would be to set the speaker to 8 ohm and use step down transformer for 100V.

Thanks for your great answer! I didn't know that the low freq would be half rated, does that only apply to using a 100v amp with 70v speakers or also with a 70v amp combined with 70v speakers?
jeroen@bmb is offline  
Old 05-17-2013, 04:10 AM
 
BobL's Avatar
 
Join Date: Nov 2001
Posts: 3,797
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 54

A 70V amp and a 70V speaker are fine, that is how it is designed to be used and the speaker should work within its rated frequency response.  Only when you are mixing the voltage ratings does the wattage and frequency range change, it is just the way transformers work.

BobL is offline  
Old 05-17-2013, 04:42 AM - Thread Starter
Newbie
 
jeroen@bmb's Avatar
 
Join Date: Apr 2012
Location: The Netherlands
Posts: 8
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Ok thanks for your clear answer.
jeroen@bmb is offline  
 
Thread Tools


Forum Jump: 

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