Member
- Posts: 56
- Joined: Mon Mar 23, 2009 5:03 pm
- Location: North Wales (Bangor)
On the recommendation of people here, I have bought a Motu 24ao to split the optical signal from my PC into a multi-channel system of speakers, to create a more three dimensional sound. But I am not clear how to connect the amps to the back of the Motu24ao. I have written to Motu and had ambiguous reply. The manual is very vague about the rear end connections so it seems that they expect anyone using this equipment to be familiar with line level sound connections.
The rear of the Motu has a row of six twelve pin sockets, each with a single pin, numbered in groups of three from 24 to 1. I have used Phoenix connectors with screw blocks to attach the connecting lines to the input of stereo amplifiers.
They are grouped in threes to give 24 three wire channels, marked on the chassis G + - . But to me the symbols + and – relate to Direct Current, not to an oscillating audio signal. I am not clear whether to wire each group as either ...
A) with every numbered channel group of three pins providing a stereo signal using the – and + as the signal line for Left and Right, and taking the G as the return. This would give me 24 stereo channels (48 speakers).
Or …
B) with every numbered channel group of three pins provides a mono signal between the + and – pins and the ground is connected to any braided shield over the line signal. This would give me 24 mono channels, (24 speakers). (In fact, none of my line connections have a braided shield – and I would have thought this form of screening only applies to very high frequency signals such as the cable from a TV aerial to the TV receiver).
I would like to make contact with anyone who is already familiar with audio line level connections. To therm the answer to this may be obvious! I am novice to audio technology, but I am experienced in the software side of the project and also the organ building needed to build and set up the console. I expect I will also need help connecting the Motu to the PC.
The amps I am using in my experimental organ are TPA7498E 2 * 60 watt 15 – 34 volts. They are not expensive and seem to give plenty of power, and they will actually run on 12 volts DC. I have a car stereo bass boost amp for the deeper pedal organ stops, driving two 20" Ambassador speakers that were thrown out of school 60 years ago. I plan to run the whole organ from a heavy duty car battery which will be re-charged from mains when the organ is not playing.
I would appreciate views and advice.
Many thanks!
John Nicholson (North Wales UK)
biopoweruk@hotmail.com
The rear of the Motu has a row of six twelve pin sockets, each with a single pin, numbered in groups of three from 24 to 1. I have used Phoenix connectors with screw blocks to attach the connecting lines to the input of stereo amplifiers.
They are grouped in threes to give 24 three wire channels, marked on the chassis G + - . But to me the symbols + and – relate to Direct Current, not to an oscillating audio signal. I am not clear whether to wire each group as either ...
A) with every numbered channel group of three pins providing a stereo signal using the – and + as the signal line for Left and Right, and taking the G as the return. This would give me 24 stereo channels (48 speakers).
Or …
B) with every numbered channel group of three pins provides a mono signal between the + and – pins and the ground is connected to any braided shield over the line signal. This would give me 24 mono channels, (24 speakers). (In fact, none of my line connections have a braided shield – and I would have thought this form of screening only applies to very high frequency signals such as the cable from a TV aerial to the TV receiver).
I would like to make contact with anyone who is already familiar with audio line level connections. To therm the answer to this may be obvious! I am novice to audio technology, but I am experienced in the software side of the project and also the organ building needed to build and set up the console. I expect I will also need help connecting the Motu to the PC.
The amps I am using in my experimental organ are TPA7498E 2 * 60 watt 15 – 34 volts. They are not expensive and seem to give plenty of power, and they will actually run on 12 volts DC. I have a car stereo bass boost amp for the deeper pedal organ stops, driving two 20" Ambassador speakers that were thrown out of school 60 years ago. I plan to run the whole organ from a heavy duty car battery which will be re-charged from mains when the organ is not playing.
I would appreciate views and advice.
Many thanks!
John Nicholson (North Wales UK)
biopoweruk@hotmail.com