sismofyt

G9 ????
« Reply #20 on: June 12, 2004, 09:32:45 AM »
Nono, the secondary is not in the signal patch.. have a look at just about any switched jack. This is very common on most preamps, even quite expensive ones. It's a bad idea, period.

Gyraf is doing it the right way, with a switch or a relay


sismofyt

G9 ????
« Reply #21 on: June 12, 2004, 09:35:45 AM »
Or so I thought  :green: (Hell, I even think I did that same on the SlowBlow thingy  :roll: )

I would advice Jakob to update the schematic to include a relay option, like the one he's using for phantompower. I really have seen quite a few preamps crap out this way..

clintrubber

G9 ????
« Reply #22 on: June 12, 2004, 09:40:04 AM »
Sorry, I'm confused here - how does a nonswitched jack after the TX (like mentioned above) get rid of the sec-winding ? Guess its switched, right ?

The G9 does use a switched instrument jack after the input-TX - if the contacts go wild the mic-signal path goes. But it'll be fine, if we can't trust switching jacks we can doubt a lot of other things as well.

   Peter

clintrubber

G9 ????
« Reply #23 on: June 12, 2004, 09:43:00 AM »
All set, no confusion any more.


Quote
I just made a FET follower with it's own PSU. Unbalanced output that can drive a mic input. Works as long as the center tap isn't grounded!


I like the impedance balanced output of that Jensen-circuit: the mic-pre sees the same R_source on both legs and just the signal on one leg.

   Peter

sismofyt

G9 ????
« Reply #24 on: June 12, 2004, 09:44:58 AM »
It may be bad wording on my part. Look at the G9 input section. This is the most common way to do it. When that jack craps out, like dust/sh*t between it's switching contacts, THAT will be in the signalpath when you plug in a microphone...

My argument is not to have a swithced jack, but a jack that's switched into the signalpath with a relay or a switch..  :?  :grin:  Makes sense?

The jacks most often have open contacts, they'll get poluted. Relays and encapsulated switches are much better...

sismofyt

G9 ????
« Reply #25 on: June 12, 2004, 09:47:11 AM »
I just connect pin3 to ground on the output XLR on the FET buffer. That's also why it won't work with grounded centertaps. Don't have any of those, so it's not a problem for me..

clintrubber

G9 ????
« Reply #26 on: June 12, 2004, 09:52:08 AM »
Our confusion is gone... Others reading this may get confused by the sequence of posts - DK & NL typing at the same time & both experiencing the inevit. posting delays  :grin:

OK, I'm out, thanks for sharing the experiences.
If I ever come to soldering me a G9 I'll definitely include a Hi-Z input option to go through both TXs. And the G9 being double-channel, I may even be tempted to split the PU's of a passive Jazz and blend after going thru both channels- or even track them separately - but that's another story altogether.

Bye,

   Peter

sismofyt

G9 ????
« Reply #27 on: June 12, 2004, 10:08:54 AM »
Regarding the Gyraf (or any other preamp using the same arrangement), the PCB doesn't really need altering as the relay could be mounted on a small PCB along with the jack. This little PCB could be controlled by the phantompower and thus be used in any preamp... just a thought..

gyraf

G9 ????
« Reply #28 on: June 13, 2004, 01:14:50 PM »
sismofyt,

I understand your concern, but I have NEVER ad switching problems in the "Rean" brand switching jacks I use - unless someone by accident had stepped in the cable, bending the contacts. I find it quite safe to use jack-switching at this point in the G9..

Jakob E.
..note to self: don't let Harman run your company..

sismofyt

G9 ????
« Reply #29 on: June 13, 2004, 01:19:31 PM »
Okay. Maybe I have just been extra ordinary unlucky  :cry: ..


gyraf

G9 ????
« Reply #30 on: June 13, 2004, 01:27:24 PM »
..or you hang around too many drunk musicians.. :razz: Do you also have the impression that the horn guys are always the worst when it comes to drinking too much and stepping in cables..?
..note to self: don't let Harman run your company..

tony dB

G9 ????
« Reply #31 on: June 13, 2004, 03:56:34 PM »
Jakob, i had a musical instrument shop from 1987 til 1996. We also did repair/service and Marshall amps (mosfet series every single one of them) came in very often to have a repair on the Reans send/returns. All the ones i sold back then went out with an extra patchlead in case the reaninterupted in action.

i still like em though  :roll:

Soeren_DK

G9 ????
« Reply #32 on: June 14, 2004, 12:13:38 PM »
A ? Again.----

Can i use this trafo 230 V ~ 2 x 15, [RS: 257-4979] from radioparts for the powersupply? Are there any specific demands for the powertrafo's
Quote from: idylldon
...it works like a champ and is as quiet as a mouse pissing on a cotton ball.

http://www.soundcloud.com/doctorsclub

gyraf

G9 ????
« Reply #33 on: June 15, 2004, 06:24:58 AM »
If it has the required VA rating, it should be fine..
..note to self: don't let Harman run your company..

Jazzy_Pidjay

G9 ????
« Reply #34 on: June 15, 2004, 08:06:43 AM »
HS Question :

i have 1n4001 and 1n5401
what is better for D13 -> D16 in the G9

?

thanks

dmlandrum

G9 ????
« Reply #35 on: June 15, 2004, 12:16:36 PM »
The drummer. :green:
Darren Landrum

Be comforted that in the face of all aridity and disillusionment
And despite the changing fortunes of time,
There is always a big future in computer maintenance.

gyraf

G9 ????
« Reply #36 on: June 15, 2004, 12:16:38 PM »
Rhytmically challenged?
..note to self: don't let Harman run your company..

sismofyt

G9 ????
« Reply #37 on: June 15, 2004, 12:18:42 PM »
Gropies!  :green: I kinda like 'em myself  :cool:

Jazzy, those are 3amp diodes, they have fatter legs than the 1N4XXX and may not fit the G9 PCB. Groupies with fat legs are no good either..

Soeren_DK

G9 ????
« Reply #38 on: June 15, 2004, 01:27:57 PM »
Thanks J...

I think i have the last parts to the g9 preamp in place now. All i need now is the money for it... ;-) I can't wait.....
Quote from: idylldon
...it works like a champ and is as quiet as a mouse pissing on a cotton ball.

http://www.soundcloud.com/doctorsclub

Jazzy_Pidjay

G9 ????
« Reply #39 on: June 15, 2004, 02:58:01 PM »
yes fat legs, but if better...

no thanks !!

it's ok for the 1n4001  :grin: