I ran it off a different circuit on the opposite phase, what else do you mean?
Don't you have different groups of electricity in your home? One for the kitchen, one for the washing machine, one for the living room and so on??
That's what I was referring to. In the US, home wiring has two phases, each 120v and 180 degrees out of phase with each other, and a neutral. Most outlets, unless for appliances, use one phase and a neutral. Not only did I put it on another branch circuit, I put it on the entire opposite phase as well.
Nevertheless I'd think of an EMI problem. Signal interconnecting is straightforward; when not done properly you might have hum, not noise.
I mailed hypex and motu, will see if either get back to me with something workable, otherwise it looks like I'll just be getting a few emu 0404s to use instead of the motu, which would be a shame.
That's assuming the emu has the same noise floor as the motu, which it doesn't. Also, the motu has trim which can adjust the output levels when the receiving a 0dbfs digital signal.
Anyway, here's the motu 16a output into emu input, and the emu output into emu input. It's not a noise floor issue. The motu into another amp with similar gain is dead silent. I'm only able to detect the noise when the motu is paired with the hypex.
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Did you try to lower the output setting of the Motu? I think it is actually a digital controlled gain stage like the inputs.
I have used a Motu 828Mk3 with my ncore400 and ucd400 amps.
I too observe large noise from Motu. I had assumed it was just the inherent noise in the anaolog stage in Motu.
Are you using an USB interface on the Motu, it isnt really isolated from the PC powersupply, so that could be another source.
Another thing i had notice was the Motu outputs are all DC coupled and can push quite a bit of DC through the ncore.
I noticed around 30mv on some channels.
I too observe large noise from Motu. I had assumed it was just the inherent noise in the anaolog stage in Motu.
Are you using an USB interface on the Motu, it isnt really isolated from the PC powersupply, so that could be another source.
Another thing i had notice was the Motu outputs are all DC coupled and can push quite a bit of DC through the ncore.
I noticed around 30mv on some channels.
a word on what is "pro" audio
NO *PRO* audio uses 1/4" TRS connectors, they use XLR, or some mass connector like ELCO or DL. If its 1/4", its prosumer.
There is a big difference, as well as the price difference.
I've dealt with a lot of MOTU gear over the years, its not the best built shall we say. My most complimentary remark is that some of it works fine.
Alan
NO *PRO* audio uses 1/4" TRS connectors, they use XLR, or some mass connector like ELCO or DL. If its 1/4", its prosumer.
There is a big difference, as well as the price difference.
I've dealt with a lot of MOTU gear over the years, its not the best built shall we say. My most complimentary remark is that some of it works fine.
Alan
I also see the dc offset on this, 32mv. The noise is present even when USB is disconnected. More fun is that when USB is connected, if I power it off my PC decides to BSOD. Probably stray voltage over USB or something.
Looks like a couple of capacitors from signal to ground on the xlr clear it right up. That said, the Motu is likely going back. Going to try a usbstreamer and an adat converter.
going with optical TOSLINK spdif or ADAT mux can give you the most galvanic isolation between the computer and the audio portion of your rig.
If you need multi channel support then ADAT can work.
If you go with USB you can get solutions that include galvanic isolation (that's called a correctly installed transformer or LED isolator), but they require more work to identify as many are not isolated.
Cheers
Alan
If you need multi channel support then ADAT can work.
If you go with USB you can get solutions that include galvanic isolation (that's called a correctly installed transformer or LED isolator), but they require more work to identify as many are not isolated.
Cheers
Alan
If the Hypex DIY stuff is overpriced, that means there's better elsewhere for cheaper. If so where's all the threads on this gear?
... no.
residential power in the US is delivered as 3 wire split phase. It's 240v with a center tapped neutral. L1 is 180 degrees out of phase from L2.
3 phase industrial power is 120 degrees, that's not what's used for residential.
Absolutely correct.. I didn't realize the step-down transformer was also a phase spliter and power balancer..
Delivered to your pole this way:
https://en.wikipedia.org/wiki/Electric_power_transmission
Delivered to your house this way:
https://en.wikipedia.org/wiki/Split-phase_electric_power
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