8 ohm to 100vLine - XLR to RCA input - diyAudio
Go Back   Home > Forums > General Interest > Everything Else
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Everything Else Anything related to audio / video / electronics etc) BUT remember- we have many new forums where your thread may now fit! .... Parts, Equipment & Tools, Construction Tips, Software Tools......

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 21st December 2010, 09:41 PM   #1
diyAudio Member
Join Date: Dec 2010
Default 8 ohm to 100vLine - XLR to RCA input

I am changing an existing system in a retirement village. They have 2 100v amplifiers. I am installing an 8 channel 8 ohm amplifier and than want to use transformers to change the output to 100v line and connect a 250 watt 100v amplifier to each output to connect to each zone of speakers. Will this work, the 8 channel amplifier is 50w per channel.

Also I want to connect the 4 wireless microphone XLR connectors to it. It can either take 2 RCA or a 3.5mm plug. Will this work or will there be sound issues. I will be splitter each input, one connection to the 8 ohm amp, the other connection into the existing Australian Monitor mixer. Will there be any losses or will it be fine. The reason for doing this is to allow the use of mulitple inputs into one output zone at the same time. As the 8 channel amplifier only allows one input to one output at the same time.
  Reply With Quote
Old 21st December 2010, 10:51 PM   #2
dmills is offline dmills  United Kingdom
diyAudio Member
Join Date: Aug 2008
Location: High Wycombe
You need to be a bit careful here, using a transformer to convert from an 8 ohm source to 100V line tends to have some issues (It can be done, but it is usually easier to make 100V line directly).

Why is the 8 ohm amp even involved here? You are running each zone off its own 250W 100V line amp anyway, these should accept a line input each, so no need for the 8 channel 8 ohm amp at all.

Me I would drive each zone off its own 100V amp (taking line level input) and produce those line level signals with the aid of a 'zone mixer' or two which is made for this job.

Cloud electronics make what is (in the UK) the canonical examples together with wall plate remote volume controls, and such, but there should be a local manufacturer of this stuff..

The radio mic receivers can probably be made to output line level which makes this a little easier.

Do note that you may have issues with the NEC here (if in the 'states), it has things to say about 100V line and there may be issues with needing plenum cable depending on how the wiring is run.

Don't try to bodge this with HIFI parts, there are correct tools for this job out there.


Regards, Dan.
  Reply With Quote
Old 22nd December 2010, 10:52 PM   #3
diyAudio Member
Join Date: Dec 2010
The reason for the HiFi amplier is the need to have r232 or IR control over input volumes, and individual zone ouptut zones. They currently have 1 8 channel mixer going into a amplifier off to an Redback A-2080 zone selector than off to wall antennuator volumes switches.
With the setup I am trying to install will give me multiple inputs, control of what input goes to what output and its volume. But the only problem is the switch from Mic XLR to AV input, and than feed 8 ohm speaker cable back into single channel 100v amplifiers to feed each zone seperately. If there is a 100v line system that can allow for zoning with volume control and be controlled via RS232 or IR than I would rather use that system. But I have been looking via Google for over a week and haven't found anything that will work.
  Reply With Quote
Old 22nd December 2010, 11:41 PM   #4
dmills is offline dmills  United Kingdom
diyAudio Member
Join Date: Aug 2008
Location: High Wycombe
Probably because you are looking for 100V line stuff, separate the amplification from the signal processing and the field opens right up.

Some possible examples:
A&H iDR 8 would almost certainly do the job (Has both RS232 in the conventional sense and SysNet for use with Crestron or AMX kit), as would a Soundweb, IIRC Shure have a DSP box as well, or even an old MediaMatrix (Peavey, but the architectural line were actually not at all bad).
Come to think of it, I bet Crestron do something usable as well.

These days this sot of multi purpose DSP based box really is the easiest way to skin this cat.

Regards, Dan.
  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
Amplifier sensitivity for RCA and XLR input Macleod Solid State 20 17th March 2010 01:43 PM
RCA/XLR input ? dejanm Pass Labs 7 17th July 2007 09:37 AM
Help converting an XLR input to RCA connectors chuck22 Instruments and Amps 6 28th July 2005 06:23 AM
Amp Input: XLR & RCA switching Devil_H@ck Digital Source 5 29th May 2004 08:54 PM
RCA to XLR ejmdiscos Everything Else 3 5th April 2004 02:44 PM

New To Site? Need Help?

All times are GMT. The time now is 09:37 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