Brown note popping sound when switching from overdrive to clean
Moderators: pompeiisneaks, Colossal
Re: Brown note popping sound when switching from overdrive to clean
That green highlight line you inserted is proper it's definitely going to proper eyelet connection on relay board
Re: Brown note popping sound when switching from overdrive to clean
On the Bass pot they have the red wire going from outer right lug on potentiometer to center that seems to be an error to me and I cut that in between otherwise it makes potentiometer bass control useless.
Re: Brown note popping sound when switching from overdrive to clean
Still have to debug the no presence issue as well?
Re: Brown note popping sound when switching from overdrive to clean
Eyes definitely get rough to see as we get older RG I know the feeling .
Re: Brown note popping sound when switching from overdrive to clean
Never mind. I figured it out. I was assuming a possible, but incorrect internal pinout for the relays.
The PCB relays I use most have the common pin (COM) between the normally open (NO) and normally closed (NC) pins, so I thought the pins from top to bottom were NO, COM, NC and coil. There is another relay pinout that is in a similar package that is arranged NO, NC, COM, and coil. For instance, the Omron G6S relays have the NO, Com, NC, coil layout I was expecting. The Omron G6A family has the No, NC, Com, coil layout that I think is in your amp.
If this is true, the relay switching and signal routing makes sense. The current schemo is attached.
A quick perusal for capacitors left open circuited didn't show up a likely suspect yet. I'll do another look.
As a safety tip, the incoming mains switching is a possible hazard. The wiring uses the old two-wire AC habit of putting the mains switch in one incoming AC wire and the fuse in the other. This may have made some sense in the days of death caps and switches, but it's not a good idea today. The schemo shows the original wiring all connected up, down in the lower left corner. A wiring variation with fewer shock hazard possibilities is shown right underneath. The difference is that the incoming AC Line (L) wire goes to the fuse first, then the mains switch, then the transformer primary. The Neutral (N) should go directly to the power transformer's other primary wire.
There are some changes I would make to what is grounded where, but if it sounds OK to you, that's fine.
Still looking for a smoking gun on the pop, and the no-presence thing.
The PCB relays I use most have the common pin (COM) between the normally open (NO) and normally closed (NC) pins, so I thought the pins from top to bottom were NO, COM, NC and coil. There is another relay pinout that is in a similar package that is arranged NO, NC, COM, and coil. For instance, the Omron G6S relays have the NO, Com, NC, coil layout I was expecting. The Omron G6A family has the No, NC, Com, coil layout that I think is in your amp.
If this is true, the relay switching and signal routing makes sense. The current schemo is attached.
A quick perusal for capacitors left open circuited didn't show up a likely suspect yet. I'll do another look.
As a safety tip, the incoming mains switching is a possible hazard. The wiring uses the old two-wire AC habit of putting the mains switch in one incoming AC wire and the fuse in the other. This may have made some sense in the days of death caps and switches, but it's not a good idea today. The schemo shows the original wiring all connected up, down in the lower left corner. A wiring variation with fewer shock hazard possibilities is shown right underneath. The difference is that the incoming AC Line (L) wire goes to the fuse first, then the mains switch, then the transformer primary. The Neutral (N) should go directly to the power transformer's other primary wire.
There are some changes I would make to what is grounded where, but if it sounds OK to you, that's fine.
Still looking for a smoking gun on the pop, and the no-presence thing.
Re: Brown note popping sound when switching from overdrive to clean
Thanks for the schematic sure if you feel some grounds need modified we can do them . Also those bypass caps with question marks are 5mf appreciate all your time
Re: Brown note popping sound when switching from overdrive to clean
I may totally revoice tonestack to a 102 or 124 dumble once I gets things straightened out .
Re: Brown note popping sound when switching from overdrive to clean
Best current (! 
) working theories so far:
> Presence
Presence would not work or would not work right if there was a high resistance in the pot from wiper to channel. To test this, unsolder the wiper wire and measure from wiper lug to one other lug. Turn the pot slowly and look for places where the resistance jumps. It should range from near-zero to the rated resistance of the pot, never more than that.
Presence would not work if either the resistor leading to the Presence control wiper was open or anomalously high, or if the wires to and from the resistor and/or OT common were open or had high-resistance solder joints.
Presence would not work if the OT common did not make good chassis contact from the jacks to the chassis.
> Popping
Still working this one. Best guess right now is that capacitor leakage from 50nf cap on the second plate is different when switching from 220K + trimmer pot resistance to ground to the 1M Master pot. But induced pop from relay coil is possible.
What is the audible quality of the pop? Is it a quick, sharp "tick!" or more of a bottle-opening "pop"?
) working theories so far:> Presence
Presence would not work or would not work right if there was a high resistance in the pot from wiper to channel. To test this, unsolder the wiper wire and measure from wiper lug to one other lug. Turn the pot slowly and look for places where the resistance jumps. It should range from near-zero to the rated resistance of the pot, never more than that.
Presence would not work if either the resistor leading to the Presence control wiper was open or anomalously high, or if the wires to and from the resistor and/or OT common were open or had high-resistance solder joints.
Presence would not work if the OT common did not make good chassis contact from the jacks to the chassis.
> Popping
Still working this one. Best guess right now is that capacitor leakage from 50nf cap on the second plate is different when switching from 220K + trimmer pot resistance to ground to the 1M Master pot. But induced pop from relay coil is possible.
What is the audible quality of the pop? Is it a quick, sharp "tick!" or more of a bottle-opening "pop"?
Re: Brown note popping sound when switching from overdrive to clean
I was doing more ferreting through the layout, and it occurred to me that I might as well capture them. Here's a link to a pdf for an annotated layout identifying the ground-to-chassis points and some of my thinking about them: https://www.dropbox.com/scl/fi/f91d518q ... 4ii0y&dl=0
The emphasis is on the chassis-as-ground connections. Chassis connections are marked and numbered, and the return paths across the chassis are marked as black dotted lines. Grounds from circuit nodes to chassis ground are in blue, and the relay ground wiring is orange. Overall, it's not too bad, accounting for the lack of hum complaints.
Here's a mildly updated schematic:
The emphasis is on the chassis-as-ground connections. Chassis connections are marked and numbered, and the return paths across the chassis are marked as black dotted lines. Grounds from circuit nodes to chassis ground are in blue, and the relay ground wiring is orange. Overall, it's not too bad, accounting for the lack of hum complaints.
Here's a mildly updated schematic:
Re: Brown note popping sound when switching from overdrive to clean
It's a definite pop sound I truly appreciate all your assistance with this . I will apply Andy's noise suppression to the relay soon .
Been abit busy with other things . Whatever we find I discovered I will have to apply it to my newest D clone my VHT50D it actually does the same darn thing
strange. If I didn't know better I would swear it's inherent with all D styles if I didn't know better? One homebrewed and one bought? I like the schematic also thanks!
Been abit busy with other things . Whatever we find I discovered I will have to apply it to my newest D clone my VHT50D it actually does the same darn thing
strange. If I didn't know better I would swear it's inherent with all D styles if I didn't know better? One homebrewed and one bought? I like the schematic also thanks!Re: Brown note popping sound when switching from overdrive to clean
Something to try for the pop; connect a 470K resistor from the lead of the 50nF plate cap on pin 8 of V1 to ground. This should be on the relay side of the capacitor, not the plate side. This gives a non-switched resistance to ground and might diminish the difference in impedance on that cap while it switches from the OD input back to the master volume control. If this makes any difference in the pop, let us know.
Re: Brown note popping sound when switching from overdrive to clean
I promise we will get back to you on this RG by the weekend my friend
Re: Brown note popping sound when switching from overdrive to clean
To those following this thread: I've never seen a Brown Note, nor the D'Lite that it's apparently derived from. I found the earlier stuff on the D'Lite and tried to correlated the two schematics. They differ in some component values and a couple of connection details. I'll try to posted a conglomerated schematic here when I finish polishing. Found some of my dumb mistakes in reducing layout to schematics too: got the pinout of a 12AX7 wrong! 