E-MU 0404 Line Input is ridiculously oversensitive

[Tranquility Bass]

I've just recently acquired one of these for some basic measurements but have found that the Line Inputs via the TRS input jacks to be over sensitive. You only need a few 10's of millivolts to overload it even though the specs says it should be able to handle Max Level: +12dBV (14.2dBu) so what gives with this device ?

I've searched through the forums and have seen other people with a similar issue. There is not any option in the E-MU control panel to select between mic and line level sensitivity so I am not sure how its supposed to give you line level sensitivity. However I have seen some pictures of the pcbs and there appears to be two relays near the input jacks so I am just wondering if they are responsible for selecting the input sensitivity ?

Currently the only way I can pad down the input level is via the recording level in windows and winding it right down to 10%.

Anyone have any experience with this device ?

cheers
david

 

[ailouros6]

Hello David
This is the USB version?
Do you have the gain knobs to zero?

 

[Tranquility Bass]

Yes it is the USB version and yes I have the gain knobs set to zero ! It's as though the line input has the same sensitivity as the mic input. Perhaps there is something wrong with this unit ?

cheers

 

[scott wurcer]

I don't have this device but I have had devices that auto switch between mic and line by detecting the ring to shield short.

 

[ailouros6]

I think both inputs have same gain,only difference is their input impedance.
Sensitivity if i remember correctly,at zero gain,was at 700mV.
Is the gain knob working?

 

[lemon]

1) There is auto switch between Line_Z input and mic (XLR) input.

2) There is different input impedance between the two input, the Line-Z input has 1Meg Ohm and Max Level: +12dBV (14.2dBu), the XLR 1.5K and Max Level: +6dBV (+8.2dBu)

3) The input potentiometers aren't multi-turn and it is difficult to achieve the level easy.

4) If you wanna to make measurement with the emu, let the input pot to minimum position (less distortion) and make an external ladder 10 or 20K attenuator.

 

[29285]

1) There is auto switch between Line_Z input and mic (XLR) input.

2) There is different input impedance between the two input, the Line-Z input has 1Meg Ohm and Max Level: +12dBV (14.2dBu), the XLR 1.5K and Max Level: +6dBV (+8.2dBu)

3) The input potentiometers aren't multi-turn and it is difficult to achieve the level easy.

4) If you wanna to make measurement with the emu, let the input pot to minimum position (less distortion) and make an external ladder 10 or 20K attenuator.

As could be expected this is identical to my EMU 0202.
Use a 6.3mm Stereo Jack instead of XLR and you access line-in symm

 

[Tranquility Bass]

As could be expected this is identical to my EMU 0202.
Use a 6.3mm Stereo Jack instead of XLR and you access line-in symm

That's what I am doing and it's way too sensitive for a line input. The Windows recording level control has to be set way down at 10 otherwise this thing will overload. Looks like I might have to lift the lid and have a good old looksee

cheers

 

[1audio]

Does the input pot have any affect on the level? It's tied into the feedback networks. If its open (cheap pot so quite possible) then you may have that issue. You should use it with the EMU drivers and as ASIO preferably. That gets the windows sound engine out of the way.

There was a whole Wiki on modding the 0404 but that may still be on hold waiting for the forum software to work right again.

 

[Nrik]

I also have an EMU 0404 USB. I use it both at linelevel and for a Behringer ECM8000 microphone.
Mine is sensitive, but not overly sensitive like yours sounds like.

After 3 years of use I experienced some DC-clicks and other nasty stuff when working the knobs and dials, so I opened it and reflowed all pots and contacts - there has been no problems since then.

Maybe this is what you need to do as well?

 

[Tranquility Bass]

Does the input pot have any affect on the level? It's tied into the feedback networks. If its open (cheap pot so quite possible) then you may have that issue. You should use it with the EMU drivers and as ASIO preferably. That gets the windows sound engine out of the way.

There was a whole Wiki on modding the 0404 but that may still be on hold waiting for the forum software to work right again.

Yes both pots are working and the only input audio option in Windows says:-

"Microphone
E-MU 0404 | USB "

Nothing about a line-in device like you get with some other cards like the Creative HD USB sound blaster.

Anyone have a schematic of this thing ?

cheers

 

[PRR]

Why not a 10K-330r-10K divider externally?

 

[1audio]

If the signal is within the dynamic rage of the input then the attenuator just limits the SNR. It should be possible to get it working right.'

Just about everything on the 0404 should be here: E-MU 0404 USB mod wiki

Schematic such as is available here: E-MU 0404 USB mod wiki

 

[Tranquility Bass]

Thanks for pointing out the schematic. I'm just wondering how the thing has so much gain to begin with because with the gain pot set for minimum (ie 20K) there doesn't seem to be much gain from input to output which I figure gets fed to the ADC.

According to the datasheet for the ADC it can handle 6Vpp. I might open it up and take some measurements because something doesn't seem right here.

regards
david

 

[Tranquility Bass]

Ok I had another look at this thing tonight. Whipped the back off and did some measurements and everything looks OK as far as levels are concerned. Relays are clicking over when I insert the TRS plugs into the sockets. Also it can handle about 4.8VRMS single ended connection before clipping so no problems with the hardware.

The issues appear to be the Windows input driver which seems to provide significant boost in software for some reason even though the hardware provides up to +65dB gain from the input level controls so why the excessive boost from the Windows Recorder control ??

Anyway of bypassing this for standard line level processing ?

cheers

 

[ergo]

Go to Recording Devices -> Properties -> Level tab and set the slider indicator to dB instead of the %.
Then adjust the slider to 0dB

... Depending on the soundcard drivers Windows sometimes enables +20dB digital gain on this slider causing the severe overload. Setting this to 0 should fix it. Same issue happens with Behringer UCA202 on Win 7 / Win 10

 

[Tranquility Bass]

Didn't know that !

In my case with this device the boost is +30dB !!

I can set it to -0.4dB but not 0 dB so that will have to do.

Thanks for that.

cheers