Login
Register
Menu
Login
Register
Home
Help
Search
Login
Register
Sound Skulptor forums
»
Build help and troubleshooting
»
DI503J Triple DI and Re-Amp
Old vs New
« previous
next »
Print
Pages: [
1
]
Author
Topic: Old vs New
September 02, 2023, 12:19:48 AM
Read 1085 times
craig.donlon@esa.int
Newbie
Posts: 3
Karma: +0/-0
Old vs New
Hi:
I've just completed a second 503J unit which works as it should and if it were not for
the fact I have a unit built from last year, I would maybe know no better. Activating the DIST switch bypasses to ground R12 (4.7M). But, when in tube mode, there is a difference between the Old and the New unit characteristics.
With the DIST switch activated, the new build sucks out more of the high frequencies - muffling the sound compared to the old version (otherwise they are identical in sound). The schematic is the same for both units but I noticed that C6 is a 100V cap in the new build compared to a 63V cap in the old but that shouldn't matter. I checked the DIST switch grounding etc and its all good and the unit is working as it should other than the DIST difference.
It was a bit of a challenge to set the 50K TR1 pot with the DIST activated on the new dull sounding build.
I swapped over the tubes between units but there is no difference in performance. Voltages on the tube stages are all more or less identical.
What would cause this and how can I get the new dull sounding unit to behave as the
old one? Is it tolerances on C6?
Regards
Craig
«
Last Edit: September 02, 2023, 12:24:32 AM by craig.donlon@esa.int
»
Logged
September 02, 2023, 10:27:22 AM
Reply #1
JPK
Administrator
Hero Member
Posts: 1118
Karma: +37/-0
Re: Old vs New
Do the units sound the same when DIST is off (up)?
If so, the issue is somewhere in TR1, C9, C10, C11, R17, R18, R19, L1.
Check the value and solder joints on these components.
Logged
JPK
September 02, 2023, 03:10:32 PM
Reply #2
craig.donlon@esa.int
Newbie
Posts: 3
Karma: +0/-0
Re: Old vs New
Hi JP
thanks or the help. C2 and C10 were reversed - everything is fine now
Regards
Craig
Logged
September 02, 2023, 03:14:39 PM
Reply #3
craig.donlon@esa.int
Newbie
Posts: 3
Karma: +0/-0
Re: Old vs New
By the way - the 503J is an amazing bit of kit that works so well on may tasks - particularly on guitar effects pedals. I am using both with a patchbay setup with stereo pedals. With the trim pot set correctly, both units are identical in all modes.
All the best
craig
Logged
September 06, 2023, 10:08:14 AM
Reply #4
JPK
Administrator
Hero Member
Posts: 1118
Karma: +37/-0
Re: Old vs New
Logged
JPK
Print
Pages: [
1
]
« previous
next »
Sound Skulptor forums
»
Build help and troubleshooting
»
DI503J Triple DI and Re-Amp
Old vs New
Login
×
Welcome,
Guest
. Please
login
or
register
.
1 Hour
1 Day
1 Week
1 Month
Forever
Login with username, password and session length