The official G9 help thread

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Clbraddock

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Apr 10, 2021
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Columbia, MO
Heard back from Analog Classics. There was a software issue with their ticketing system and they didn't know about the order. Their representative was very nice and fixed everything. Just wanted to mention they eventually took care of me in case others saw my post and became concerned. Glad they are still in business since it looks like they have a cool selection of pcbs.
 

HyprDrivr

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Nov 5, 2020
Messages
48
I have a small video restrospective on my build on youtube.
Looking at it now it seems quite pointless but i guess someone could find some use for it.
 

VK

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Dec 25, 2021
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2
Location
EU
Loving the G9 and this forum!

How would one go about adding a jewel light for the on/off switch?
 

3nity

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Dec 30, 2005
Messages
3,556
Location
MTL, CANADA
Hi good people.
First attempt with a tube build.
I'm planning a point to point 1 channel.
I was wondering if I could use an Antek toroidal for power?
TIA.
 

gyraf

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Aarhus, Denmark
If Antek makes a transformer that will give you 240V/30mA, 12V/1A and 48V/50mA (DC ratings) then you're probably fine..
 

lindes

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Aug 10, 2015
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Brussels
Hello everyone, I am a new member, guitarist and singer, and owner of a G9 bought second hand. I would like to get some advice from you for some problems I have with this preamplifier.
When I connected the G9 to my table I immediately had a humming noise on both channels. I opened the box and saw that one of the input transformer covers was next to the main circuit. I tested the other three and the cover comes off easily.
My questions are: shouldn't these OEP transformer covers be soldered to the base?
The ground loop of the box was connected to the metal part of the input XLRs. Shouldn't it be connected to one of the three XLR connections?
I am attaching photos to see what is going on.

Thanks for your help!
 

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gyraf

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..yes, those housings should have been soldered to the base plate under the transformers. I'm sure we talked about this many times before in this thread..

/Jakob E.
 

lindes

Member
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Aug 10, 2015
Messages
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Location
Brussels
..yes, those housings should have been soldered to the base plate under the transformers. I'm sure we talked about this many times before in this thread..

/Jakob E.
Thank you for the answer. I didn't go through the 118 pages...yet. I suppose I will.
 

zaraxisof

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Aug 2, 2017
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Greece
Thank you for the answer. I didn't go through the 118 pages...yet. I suppose I will.
It seems it's not in this thread.



This has to be done before installing and solder their pins to PCB. I forgot to do so while populating pcb so i am in the same boat as you. Shielding screening cans after having installed and soldered trafo in place. Base can be moved under the trafo. I thought it wasn't obligatory to get them stable and that gnd pin must be soldered to the base and upper housing together.
Since i built it i have them installed by just push 'em tight enough and get touched with the base by physical contact. I get continuity in DMM. Truth is i has no hum or noise problems.
Well, if i turn input and output knobs bigger than "3 o'clock" i get a little hum but i guess this is normal. Or no?

Anyway @lindes : if you find a way of how to do it without having to de-solder every pin, every trafo, please share. I tried hard in the past with no success. It's very hard to solder in the base having it between the above of pcb and under the trafo and without damaging the plastic trafo's insulation.

PS. Now that i think again of it, having the base screeining can not soldered to trafo's gnd center pin, it means it isn't grounded at all. That's why i get continuity from base to upper housing can, but i guess they are not grounded in the circuit lol.
I have to de-solder trafo? Is this safe? Or just run a cable from upper can to a gnd point?
 
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