weiss

Re: G-PULTEC problems, please help!
« Reply #700 on: September 24, 2017, 01:56:27 PM »
I bought 2 power trafos for a stereo g pultec project years ago with following specs from micandmod (https://micandmod.com/hardware-parts/223-power-transformer-pultec-eqp-1a-gyraf.html):

Voltages, primary: 0-115V, 0-115V
Voltages, secondary: 0-9V/1A, 0-220V/50mA, 0-11V/500mA

can these be used to power 2 pcb's? i am worried about the 11V compared to the 5V secondaries offered with this one:
 https://www.don-audio.com/g-pultec-power-trafo-sec-220v-9v-5V
"We're gonna have a good time tonight - Let's calibrate, it's all right!"


petermontg

Re: G-PULTEC problems, please help!
« Reply #701 on: September 24, 2017, 03:53:40 PM »
I bought 2 power trafos for a stereo g pultec project years ago with following specs from micandmod (https://micandmod.com/hardware-parts/223-power-transformer-pultec-eqp-1a-gyraf.html):

Voltages, primary: 0-115V, 0-115V
Voltages, secondary: 0-9V/1A, 0-220V/50mA, 0-11V/500mA

can these be used to power 2 pcb's? i am worried about the 11V compared to the 5V secondaries offered with this one:
 https://www.don-audio.com/g-pultec-power-trafo-sec-220v-9v-5V

 I used the G9 one from Don Audio without any issues in  stereo version.
Don't cheap out on the shielding....... Save yourself a headache,

petermontg

Re: G-PULTEC problems, please help!
« Reply #702 on: September 27, 2017, 04:02:49 PM »
So, I did a little mod on mine today.

A little switch to bypass the whole mid boost section connecting back to the 0mh pin which leads back to the lowend boost and high freq cut.

Unit sound so much better when using the lowend only, really opens it up and you can have lowend boost for days.
Going to put it under scope tomorrow see how its reacting.

Switch connecting is
Pin 1 (bottom) - 0mh
Pin 2 (middle) - output from SRPP
Pin 3 (top) - to filter input.

Ground stayed the same connect straight to filter.

Have fun, if anyone try's it.

Best
Peter

darkus

Re: G-PULTEC problems, please help!
« Reply #703 on: October 12, 2017, 02:57:32 AM »
Hi all!

Im still having issues with my build. The output is really low and thin, I can hear the filters are working its just that the signal sounds very broken, thin and low gain.

Ive checked my xlr wiring and terminating resistors are correct. Im using wired Alpha switches and LL5402 in/out. Don Audio PT.
I read that I should recalculate the big watt resistor value for the don audio PT, currently I have one thats suggested in the bom. Is there a chance my tube is broken? I havent actually measured what voltage the PT is giving to the tube.

« Last Edit: October 12, 2017, 03:03:52 AM by darkus »

petermontg

Re: G-PULTEC problems, please help!
« Reply #704 on: October 13, 2017, 08:11:37 AM »
What toroidal are you using? Check your voltage after the 3K3/2W. I doubt your tube is broken. There are 3 voltage to power the SRPP. 

weiss

Re: G-PULTEC problems, please help!
« Reply #705 on: March 28, 2018, 02:39:15 PM »
Hey guys, I'm having problems figuring out how to wire the RM-8 inductor by don audio..
https://www.don-audio.com/G-Pultec-Inductor-RM8-22mH69mH169mH269mH

the connections on the pcb are 2 per inductor but the rm8 combines all 4 together with one output for each value.
so which pin should be used for the second connection of each value?



I hope you get what I mean..

thanks
Ansgar
"We're gonna have a good time tonight - Let's calibrate, it's all right!"

Re: G-PULTEC problems, please help!
« Reply #706 on: March 29, 2018, 04:31:17 AM »
Hey guys, I'm having problems figuring out how to wire the RM-8 inductor by don audio..
https://www.don-audio.com/G-Pultec-Inductor-RM8-22mH69mH169mH269mH

the connections on the pcb are 2 per inductor but the rm8 combines all 4 together with one output for each value.
so which pin should be used for the second connection of each value?

I hope you get what I mean..

thanks
Ansgar

The pic you attached

You see how one step on the switch connects to the end of two inductors at a time?

You are just tapping into windings on a single inductor and setting them up to switch in series instead of using single inductors.

Gustav


weiss

Re: G-PULTEC problems, please help!
« Reply #707 on: March 29, 2018, 06:43:08 AM »
The pic you attached

You see how one step on the switch connects to the end of two inductors at a time?

You are just tapping into windings on a single inductor and setting them up to switch in series instead of using single inductors.

Gustav

ahhh now i get it.. thanks Gustav!
Ansgar
« Last Edit: March 29, 2018, 07:14:25 AM by weiss »
"We're gonna have a good time tonight - Let's calibrate, it's all right!"

jon83

Re: G-PULTEC problems, please help!
« Reply #708 on: May 30, 2018, 03:14:11 PM »
Hi all,

Can someone tell me what the resistor values on the Don Audio filter board are? On the original they're marked as 1k, 1k, 10k, and 75r, is that right? If so, what do they correspond to, R1, R2 etc. Cant seem to find this anywhere online.


weiss

Re: G-PULTEC problems, please help!
« Reply #709 on: June 27, 2018, 07:51:02 AM »
Hey guys.
I experienced some weird behaviour with my new g pultec. Everything works except in one position (60Hz) of the low frequency rotary switch (2x6) it is louder than the other selectable frequencies (20-100Hz). I checked the wiring for mistakes but i couldn't find an explanation for this behaviour. any ideas? is the switch broken?? it also makes "sound" during switching, whereas the other switches just mute during switching...

thanks,
Ansgar
"We're gonna have a good time tonight - Let's calibrate, it's all right!"


gyraf

Re: G-PULTEC problems, please help!
« Reply #710 on: June 27, 2018, 08:36:01 AM »
Louder as in: if you test it at 60Hz signal - or louder like in "all frequencies are boosted"?

First is a property of eq's :-) - last points to a defective capacitor or connection..

Jakob E.

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

weiss

Re: G-PULTEC problems, please help!
« Reply #711 on: June 27, 2018, 12:26:36 PM »
Louder as in: if you test it at 60Hz signal - or louder like in "all frequencies are boosted"?

First is a property of eq's :-) - last points to a defective capacitor or connection..

Jakob E.

second one!
let me try to explain: in the low boost section i can select (rotary)

20Hz, 30Hz, 50Hz, 60Hz, 80Hz, 100Hz

When i switch to 60Hz the whole signal gets boosted like 5 db's or so. A single frequency is not the problem but the overall loudness difference. but only on this switch position, all the other positions i can select in the low section work like expected. I resoldered the whole switch connections so that leaves a dead cap?
« Last Edit: June 27, 2018, 01:43:22 PM by weiss »
"We're gonna have a good time tonight - Let's calibrate, it's all right!"

weiss

Re: G-PULTEC problems, please help!
« Reply #712 on: June 29, 2018, 06:33:18 AM »
which capacitor would be most likely responsible for this? anyone?
"We're gonna have a good time tonight - Let's calibrate, it's all right!"

gyraf

Re: G-PULTEC problems, please help!
« Reply #713 on: June 30, 2018, 01:48:43 AM »
..the one associated with the problematic step on the switch...
..note to self: don't let Harman run your company..

weiss

Re: G-PULTEC problems, please help!
« Reply #714 on: July 10, 2018, 03:27:05 PM »
..the one associated with the problematic step on the switch...

sorry for being so dumb. I found the problem. It was indeed a bad connection.
Thanks Jakob!
"We're gonna have a good time tonight - Let's calibrate, it's all right!"

andow

Re: G-PULTEC problems, please help! New
« Reply #715 on: October 10, 2018, 06:29:27 PM »
Can somebody tell me if a Haufe RK310/2 would be suitable as input transformer?
« Last Edit: October 14, 2018, 06:09:52 AM by andow »

gyraf

Re: G-PULTEC problems, please help!
« Reply #716 on: October 13, 2018, 03:04:08 PM »
Impossible to tell. Try and report back?

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


 

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