• Registered: 2011-08-17
  • Posts: 75

Topic: Best UFX Line Input Setting for ISA ONE preamp + BluBird microphone ?

Hello,

First I am sorry to ask questions that may be obvious to many of you, but I am a beginer so please forgive me !

I have bought the Fireface UFX and it works VERY well ! (Also in Reaper for mixing, after a long time for understanding the TotalMix FX software ...). I record mainly Vocals (for the question) and Guitar + perc.

I would love to optimize the following chain :

A blue BlueBird Microphone, an ISA ONE preamp and the rear Line Input of the UFX.

My concern is first the setting of the UFX level (Lo Gain .. or +4 dBu  ... or -10 dBV ???)

As I do not understand all, but I know it is related to the ISA ONE Line Output, I report underneath the technical specification of the "3 members of the chain".
If you could also help me with the settings of the Preamp (Low/ISA 110/Med/ High) as it is related to the microphone and maybe with the UFX, I would be delighted !!

Thanks a lot for your help (and if possible for some explainations ...)

Philippe

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THE RME FIREFACE UFX :
Rear Input switchable :
Reference    0 dBFS@    Headroom
Lo Gain        +19 dBu    15 dB
+4 dBu        +13 dBu    9 dB
-10 dBV    +2 dBV        12 dB

THE ISA ONE PREAMP :  Mic Input Response
• Gain range = 0dB to 60dB in 10dB steps + 20 dB of variable gain
• Input Impedance, variable as follows: (Switched Impedance setting Equivalent Input Impedance at 1kHz)
Low = 600 Ohms / ISA110 = 1400 Ohms / Med = 2400 Ohms  / High = 6800 Ohms
• EIN (equivalent input noise) = -126dB measured at 60dB of gain with 150 Ohm terminating impedance and 22Hz/22kHz band-pass filter
• Noise at main output with gain at unity (0dB) = -97dBu measured with a 22Hz/22kHz band-pass filter
• Signal to noise ratio relative to max headroom (9dBu) = 106dB
• THD at medium gain (30dB) = 0.0009% measured with a 1kHz -20dBu input signal and with a 22Hz/22kHz band-pass filter
• Frequency response at minimum gain (0dB) = -0.5dB down at 10Hz and -3dB down at 125kHz
• Frequency response at maximum gain (60dB) = -3dB down at 16Hz and -3dB down 118kHz
• CMRR=98dB (Channel 1, 1kHz, maximum gain with +24 dBu input)
• Crosstalk Channel to Channel: with 10dB@1kHz input to chA, chB output =104dBrA. With 10dB@10kHz input to chA, chB output = 84dBrA
• EIN (equivalent input noise) = -126dB measured at 60dB of gain with 150 Ohm terminating impedance and 22Hz/22kHz band-pass filter
• Noise at main output with gain at unity (0dB) = -97dBu measured with a 22Hz/22kHz band-pass filter
• Signal to noise ratio relative to max headroom (9dBu) = 106dB
• THD at medium gain (30dB) = 0.0009% measured with a 1kHz -20dBu input signal and with a 22Hz/22kHz band-pass filter
• Frequency response at minimum gain (0dB) = -0.5dB down at 10Hz and -3dB down at 125kHz
• Frequency response at maximum gain (60dB) = -3dB down at 16Hz and -3dB down 118kHz
• CMRR=98dB (Channel 1, 1kHz, maximum gain with +24 dBu input)
• Crosstalk Channel to Channel: with 10dB@1kHz input to chA, chB output =104dBrA. With 10dB@10kHz input to chA, chB output = 84dBrA

THE BLUE BLUEBIRD MICROPHONE :
Transducer Type : Condenser, Pressure Gradient
Polar Pattern : Cardioid
Frequency Response : 20Hz – 20kHz
Sensitivity : 27.0mV/Pa at 1kHz (1 Pa=94dB SPL)
Output Impedance : 50 Ohm
Rated Load Impedance :  >1k Ohm
Maximum SPL : 138 dB SPL (2.5k½, 0.5% THD)
S/N Ratio : 87 dB-A (IEC 651)
Noise Level : 7 dB-A (IEC 651)
Dynamic Range : 131 dB (@ 2.5kOhm)
Power Requirement : +48V DC Phantom Power (IEC 268-15)
Weight / Dimensions : 480g / 222mm x 45mm

  • From: Connecticut, USA
  • Registered: 2011-08-01
  • Posts: 376

Re: Best UFX Line Input Setting for ISA ONE preamp + BluBird microphone ?

HI Philippe,
It does not state anywhere I could find in the ISA manual but since the outputs are XLR I'm assuming they are balanced which is typically +4.
You will need to go into the 1/4" line inputs of your UFX so you will need balanced 1/4" TRS male to XLR Female cables.
You might want to get the optional Digital I/O card for the ISA One at some point . This way you don't have to use up your analog I/O of the UFX.
I've never used that Blue Microphone but it's specs seem typical. From looking at the manual the ISA-110 impedance would be correct settings.



Thanks Chris

Chris Ludwig
North East USA Sales | Synthax/RME
www.facebook.com/RMEAmericas
Twitter @RMEAmericas

ChrisLudwig's Website

  • Registered: 2011-08-17
  • Posts: 75

Re: Best UFX Line Input Setting for ISA ONE preamp + BluBird microphone ?

Thank you Chris,

I have already connected my ISA ONE output to the UFX input 3 (rear Line Input) with an XLR / Jack male TRS cable.
I did not know that XLR balanced signals are typically used with the +4 dBu parameter (that is the answer to my initial question).
The purchase of a Digital I/O card is not on my plan right now (but the sound I get from the BlueBird + ISA ONE analogic + the Fireface is very close to what I was expecting ...)
I will use the ISA-110 impedance setting for the mike.

Thanks again and Have a nice day,
Philippe

  • Registered: 2011-04-04
  • Posts: 41

Re: Best UFX Line Input Setting for ISA ONE preamp + BluBird microphone ?

Philippe,

I have an ISA 1 digital. I usually use the digital option, but I've tried the analog line out to my UFX and it sounds great.
Just a note that you don't have to use the ISA-110 option (although that is what the focusrite sound is all about). You can play with the impedance to get different sounds from the mic.
The Med and High settings will give you more highs and "grit" the Low settings will mellow things out. Try it out!