Description
This is our take on the 2ch G9 full tube mic/line preamp. Variable gain input tube that drives tube SRPP output stage. Inputs and outputs are balanced.
OEP in and OEP out with mu-metal shielding. OEP transformers deliver improved linearity, more low and top end compared to lundahls. We have tested and measured it side by side extensively in curvetracing and listening environments. Many recording studios agree with our findings.
Custom made metal enclosure. Powderpainted and screenprinted.
Relay driven true-bypass.
We have selected 2 different tubes for this unit. Shortplate JJ 12AU7 or longplate JJ 12AU7. Tubes play a big roll in the character. I encourage to test different 12AU7 tubes by different makers also NOS. They will all sound similar, but different. Test and find your favourite.
I will install a shortplate or longplate, lets discuss which you prefer. Shortplate sounds bright, longplate is more balanced. Character is the same, but strings will love the shortplate. Vocals usually prefer longplate.
Controls:
INPUT select.::
*BYP means Bypass where relays are switching the input XLR straight to output XLR.
*Line means line input that feeds the input transformer though a -26dB PAD.
*Mic means microphone input this feeds the input signal straight to the input transformer.
*+48V means microphone input with added phantom power.
GAIN.::
This is stepped knob that alows you to set gain in 11 fixed positions
LOW-CUT.::
THis is a stepped knob that alows you to select low-cut curves.
OUTPUT.::
This is an output volume control potentiometer.
PHASE.::
This is a phase switch that lets you invert the phase on the output of the unit.
Maximum gain is around +60dB with gain and volume maxed.
Added modifications:
1) Input switch has Bypass position that is controlling 4 bypass relays on the xlr jacks. When the unit is not powered signal is bypassed.
2) Extra positions for Low Cut switch to extend the options. Cut curves are shown on the picture. Flattest curve is unit freq response.
3) PCB redesign and changes to reduce noise.
Original G9 was designed by Gyraf Audio at https://www.gyraf.dk/
The case option will provide you with:
1) Metal enclosure, powderpainted and screenprinted. All the holes laser cut.
2) Preamp PCBs x2
3) Front panel switch PCBs x2
4) Power Supply PCB x1
5) Bypass PCB
6) 230/115VAC switch.
Original Gyraf G9 preamp PCB can be fitted inside the case also, holes are pre-cut.
Assembly instructions, notes and BOM can be found on our G9 preamp product page.
Cutomer feedback:
Sudu Mixing and Mastering Studio :
Sounds amazing on pretty much anything, adds warmth and makes the top end more open.
Funki Factori Studio:
Funki Factor studio has over 50 preamps to choose from. But lately we’ve been using the GiX tube amplifier built by VanDaal at least as diligently as the 1073. While testing different tubes, we’ve stuck with NOS Mullard tubes, which give an even frequency characteristic over the entire spectrum, while adding a nice harmonic distortion to the overall sound. The preamp also has a line input and an instrument input, making this unit exceptionally versatile. We use the GIX not only as a microphone preamplifier and a DI box, but also as a line amplifier and a distortion box in parallel processing. One of the best buys this year!
