reamping issue: level too low! (Radial JCR/Behringer UMC202HD)

Kieth, it says "maximum output +3dBu" in the spec sheet. The Berry UCA 202 is a -10dBV device and the input clips at one volt and it is a unity gain converter. That is fair enough because the 202 works better than it has a right to for 25quid, Yes, the UMC range ARE cheap but you would thing they could go $1/2 for an NE5532 and a couple of resistors and caps? SMT would get four outputs on less than a chrissytime stamp!

Dave.
Ok. Well, I guess I missed the MAX part. So, if I compare that to the RME device (Fire something?) I was looking at, its max for the -10dBu reference (i.e., consumer) was +2dBu @ 0dBFS, so we can assume that at least this particular u-Phoria model is only outputting something like a "consumer" line level. If the other models in the lineup are spec'd the same, then a passive reamp box might not be the right solution, at least not one that expects "pro" line level output. (Perhaps we have to assume when the reamp box is 2x the price of the interface there may be a different set of assumptions at work in the design teams.)

Where we got the idea we are supposed to get something we didn't pay for, I don't know...
 
I think one hint could be that the interface is powered from the USB 5V bus power. You can convert that to higher voltage IF you don't need much current and you can get a pretty good deal of current out of it IF you don't need much voltage. You can't have both, though. In order to be legitimately low impedance, it needs to be able to deliver a good deal of current, so it kind of can't be expected to maintain much voltage at all.
 
Ok. Well, I guess I missed the MAX part. So, if I compare that to the RME device (Fire something?) I was looking at, its max for the -10dBu reference (i.e., consumer) was +2dBu @ 0dBFS, so we can assume that at least this particular u-Phoria model is only outputting something like a "consumer" line level. If the other models in the lineup are spec'd the same, then a passive reamp box might not be the right solution, at least not one that expects "pro" line level output. (Perhaps we have to assume when the reamp box is 2x the price of the interface there may be a different set of assumptions at work in the design teams.)

Where we got the idea we are supposed to get something we didn't pay for, I don't know...

Tomorrow Keith I am going to play a track out of this HP lappy via a 202 and feed my HT-20 head (into a Greenback) then check the SPL I can easily achieve. I am pretty certain I will be able to get 90dB SPL at the speaker fret. OP is IMHO doing something very wrongly OR some part of the chain is rather busted.

Dave.
 
I think one hint could be that the interface is powered from the USB 5V bus power. You can convert that to higher voltage IF you don't need much current and you can get a pretty good deal of current out of it IF you don't need much voltage. You can't have both, though. In order to be legitimately low impedance, it needs to be able to deliver a good deal of current, so it kind of can't be expected to maintain much voltage at all.

"Bus power" is often blamed for all sorts of interface ills but the facts do not stack up. My NI KA6 has 4 audio inputs, 4 outs, MIDI and S/PDIF and still manages an output of +11dBu or 3.5V rms. I have a USB power tester and the AI draws about 480mA. There ARE compromizes. The pahntom current is nowhere near proper specc but there is easily enough for my two AKG p150s.

In any case you don't need very much "power" at all to put out +10dBu or so, even into 600 Ohms.

Dave.
 
Tomorrow Keith I am going to play a track out of this HP lappy via a 202 and feed my HT-20 head (into a Greenback) then check the SPL I can easily achieve. I am pretty certain I will be able to get 90dB SPL at the speaker fret. OP is IMHO doing something very wrongly OR some part of the chain is rather busted.

Dave.

Me thinks something is amiss also.Doesn't that Radial only have to output guitar pickup levels for reamping.

G
 
But what could i actually be doing wrong?
I have a pro level reamp box (and since its expensive and 'pro' i expect it to be not that picky about its input).
It has a balanced/unbalanced line input, i'm feeding it through a rather cheap but not necessarily bad interface with an unbalanced line level signal with everything maxed out.
And in result the output of the JCR is little below guitar level.

When plugging a cheap behringer mixer board between the interface and the JCR everything is fine, but noisy, with no difference whether i feed the JCR balanced xlr or unbalanced 1/4".

So i guess +3dBu just isnt enough.

The UMC404HD and a steinberg ur44 should arrive the next days, if the ur44 works it's really just the low level.
 
Oooo---Kay. I have done the test, worked better than I expected. Attached is the file I played, one of my son's early attempts with a looper.

The UCA 202 was fed from this i3HP laptop and the left RCA fed the jack input of a Blackstar HT-20 amplifier, the "clean" channel and the amp is not one of high gain (I have the figure somewhere) . The track averaged -15dBfs (16 bit device) and I had no trouble at all in producing very unsociable levels. No need to ram the SPL (C) meter onto the fret, I could easily acheive 95-102dB SPL a meter and a half away in the room. I had ample gain and master VC travel left and the sound was loud but not in the least "strained".

Yes, the SPL meter is a cheap ass' unit from the now defunct Maplin (but the model is widely found o'net for $20 or so) and should you think it inaccurate? The room backgound is 28dB and Radio 3 in my living room system at pleasant levels reads ~70dB at 1.5mtr from the centre speaker.

The UCA puts out around 75mV on the jack tip* for that tune, a rather neat -20dBu! So, even if the Berry IS a feeble -20dBu it should STILL blow the *its off any 1/2 decent guitar amp!

There is something very bloody odd going on with OP's rig.

*Measured with a Fluke 83 DMM. I would suggest a similar test for this offending setup.

Dave.
 

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recieved the UR44 today.
the output of the additional line outs on the back is high enough to feed the amp a signal of the same level as the guitar when playing normalized DIs with the JCRs output level at 3 o'clock.
Thats enough headroom for me, so i'm fine with that.

what i don't like right now is the amount of noise the UR44 puts into the amp, even when nothing is played there is plenty of noise.
Inputs are muted in the DSP mixer, but there is still coming noise from the UR44.
My amp is pretty noisy right now, and the additional noise is slightly audible when playing and really is annoying while palm mutes... pretty weird and not good for any recordings.
 
recieved the UR44 today.
the output of the additional line outs on the back is high enough to feed the amp a signal of the same level as the guitar when playing normalized DIs with the JCRs output level at 3 o'clock.
Thats enough headroom for me, so i'm fine with that.

what i don't like right now is the amount of noise the UR44 puts into the amp, even when nothing is played there is plenty of noise.
Inputs are muted in the DSP mixer, but there is still coming noise from the UR44.
My amp is pretty noisy right now, and the additional noise is slightly audible when playing and really is annoying while palm mutes... pretty weird and not good for any recordings.

What does the noise sound like? 60hz hum or static?

Hell, post a sample. :)
 
...
what i don't like right now is the amount of noise the UR44 puts into the amp, even when nothing is played there is plenty of noise.
Inputs are muted in the DSP mixer, but there is still coming noise from the UR44. ....
The recommendations I've read are to use the longer, balanced cable runs from the interface/console output to the reamp box (for less chance of noise), and a short, patch-type cable from that to the amp.
 
recieved the UR44 today.
the output of the additional line outs on the back is high enough to feed the amp a signal of the same level as the guitar when playing normalized DIs with the JCRs output level at 3 o'clock.
Thats enough headroom for me, so i'm fine with that.

what i don't like right now is the amount of noise the UR44 puts into the amp, even when nothing is played there is plenty of noise.
Inputs are muted in the DSP mixer, but there is still coming noise from the UR44.
My amp is pretty noisy right now, and the additional noise is slightly audible when playing and really is annoying while palm mutes... pretty weird and not good for any recordings.

Ok so, when you plug guitar straight into the guitar amp you get a reasonably good signal to noise ratio? Can you record 20 secs of guitar at ~-18dBfs then shut tf up, palm the string and give us 20 secs of just amp noise? It saves ME hassle if you just attach as mono 320k MP3.

The result of the same recording DI'ed into the 44 should, when re amped give just about the same S/N figure because 1, guitars and amp are pretty noisy and 2, digital recording is SO much better (even 16bit) that it is to all intents perfect.

Tomorrow I shall do a similar test and post the results. What btw is the make and model of your guitar amp?

Dave.
 
Attached is one of many riffs my son recorded years ago.
The setup is an 8i6 line out feeding the HT-20 head (no re-amp kit at all, just a 5mtr guitar cable*)

An akg P150 SDC feeds my NI KA6 and records on a tower in Samplitude. The mic is up against the fret of the cab loaded with a Greenback. The level in the room is around 85-90dBC.

When the clip stops I stop the track and so you are hearing the residual noise of the 8i6 output plus amp noise. The master and gain controls on the amp were set such that a Mex Strat produced the same levels for E/A chords, pots all at max and pups switched to centre+bridge.

I think most here will agree there is no real noise issue here?

*Plug for messrs Neutrik here. I reported a counterfeit cable (Maplin!) to them some years ago and they sent me a Silent Plug super quality 5m guitar lead!

Dave.
 

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