Some G9 questions

[Kev]

yep,
it's easy to say too much
yes, the Hammonds are ridiculous

errr think about another famous US trafo

I got the same exploitation factor from a distributer very local to me.
My work place even did business with them in there core work area.
... and they also knew who I was when I asked for the quote.

shut up Kev

burnt bridges ... :roll:


it's all good

 

[mnats]

... and they also knew who I was when I asked for the quote.

Ah, the price of fame!

I wonder how much of this is driven by the manufacturers themselves selling at higher wholesale prices to foreign distributors. Maybe it's time to support local manufacturers like Harbusch?

http://www.users.bigpond.com/harbuch/harbuch/audiotx2.htm

 

[Kev]

[quote author="mnats"]I wonder how much of this is driven by the manufacturers themselves .... Maybe it's time to support local manufacturers like Harbusch?[/quote]

From what I know the manufacturers price was good and the locals tried to do the audiophool price

stay tuned for a couple of options from Joe.
localy made ... me thinks

 

[fjh]

I'm fairly new here, so please bear with me. Has anyone ever noticed the discrepancy between the G9 schematic and the PCB layout?

The PCB layout (Lorlin switch panel board) shows R13 simulaneously connected to R11, R12, and pin 11 of the "GAIN" rotary switch, while the schematic shows R13 and R11 connected to the switch, but not R12. Which is right?

 

[gyraf]

Hi fjh,

Yes, there's a slight flaw in the schematic - it's mentioned somewhere in this forum before.

The PCB's are known good, however..

Jakob E.

 

[fjh]

:shock:

Thanks, I'll note the correction.

 

[compactaudio]

SSL is good.

 

[dukasound]

Hi
Slowly progress :sad: but I am satisfied :grin: .
Here is a board. I need only TL783 and 0,22uF interstage caps.
Yes, chassis too.

What about OEP :?:
Easier than I mean. I slowly sanded and used some soldering paste (without acids) and this is first can what I soldered.

Others are better
Duka

 

[zei]

i,m thinking of building a G9 from Jacob,s at Gyraf schematics.
However Friends of mine uses the Studio Projects VTB1 Mic Preamp when recording and they claim that this little thing is "all that"

how is the G9 compered to the new VTB1 ?
Anyone who has any thoughts on this?

regards

Z

 

[robomatique]

[quote author="zei"]i,m thinking of building a G9 from Jacob,s at Gyraf schematics.
However Friends of mine uses the Studio Projects VTB1 Mic Preamp when recording and they claim that this little thing is "all that"

how is the G9 compered to the new VTB1 ?
Anyone who has any thoughts on this?
[/quote]

The G9 is in a different league. I haven't heard the VTB1, and some of the cheap stuff is actually ok, but the G9 is great and is being compared to units costing 10-20 times the VTB1.

I can almost guarantee that the vtb1 works in low voltage while th G9 is a real old school high voltage tube unit with transformer balanced ins and outs... can't compare them...

 

[tony dB]

just a little hint/question towards the above picture from Duka...

Shouldn't the pin in the smallest hole (in between the 2 rows) touch the frame to ground it?
If that's not the case i have some serious desoldering to do :roll:

Cheers,

Tony.

 

[gyraf]

yes, the ground pin should be soldered to the mu-metal shield..

 

[dukasound]

Hi
Whats your opinion about mounting 7812 voltage regulator (with insulator) on the bottom of chassis like on this pic?

Duka

 

[gyraf]

That works well, if the contacts are good. Remember that they carry 600mA heater current.. I would probably prefer to solder the wires onto it..

Jakob E.

 

[alk509]

[quote author="dukasound"]

[/quote]

Hey Duka,

Gotta insulate the other side as well... And the inside of the actual screw hole. And I wouldn't use that little socket for the regulator - I'd solder wires to the pins.

I personally don't think it's a good idea. :?

Peace,
Al.

 

[dukasound]

Hi Al
I was thinking to insulate screw. I asked is this good idea, because all said that 7812 need big heatsink. I have a couple bigger heatsink but this would be easier.
Duka

 

[gyraf]

cooling to the baseplate of the unit is generally enough for the G9. But you will need to assure that the 78S12 is isolated from chassis. Even though the cooling tab is sitting at ground potential, it will give you a lot of ground-loop hum otherwise.

Jakob E.

 

[tony dB]

i have some if these clip-on heatsinks, are they sufficient for this purpose?

 

[gyraf]

Depends on their rating - (degrees centigrade/W)

http://www.groupdiy.com/index.php?topic=5168

Jakob E.

 

[dukasound]

[quote author="gyraf"]cooling to the baseplate of the unit is generally enough for the G9. But you will need to assure that the 78S12 is isolated from chassis. Even though the cooling tab is sitting at ground potential, it will give you a lot of ground-loop hum otherwise.

Jakob E.[/quote]
Hi Jakob
Can I do it if I insulate 78S12 or not?
Thanks
Duka