Rock/Jazz Switch

[harleyboy2112]

I have a question about the Rock/Jazz switch. I modified the normal channel of my Twin Reverb with a Dumble style tone stack. Going from Rock to Jazz causes a great drop in my signal. I"m assuming that's not normal.
I didn't incorporate the PAB switch so I didn't add the 22M resistors I seen on the dumble schematics since I'm pretty sure they are just there to prevent popping while switching the PAB.
Is the drop in volume normal?

[Structo]

Yes, it is normal for the Jazz setting to be attenuated and cuts the top end.

I suppose if you re-adjust the knobs for it, it could be usable but most guitarists probably glue it to the Rock setting.

As has been mentioned it can be omitted but some claim it is part of the Dumble ODS tone.

[ic-racer]

The Jazz setting on my Twin conversion is great for hollowbody guitars. It is also good when recording solid body guitars with a clean sound. It flattens out some of the dynamics making it easier to get on disk without additional compression.

[jam-mill]

Check out this demo (https://youtu.be/ap6odoC4itw) and note the amp settings; appears the J/R switch is in the 'jazz' setting.

I use the 'jazz' setting and like it, but it definitely requires a significant change to the tone stack settings - at least for me.

-jack

[ic-racer]

I found an example of my HRM-style with a hollowbody using the Jazz setting:
https://youtu.be/MdTesmrUOME

[Structo]

That guitar sounds great!

[Smokebreak]

Whatever this one is, it sounds pretty good in what appears to be jazz
https://youtu.be/9U1mrbqyEyw

[glasman]

Yes, it is normal for the Jazz setting to be attenuated and cuts the top end.

I suppose if you re-adjust the knobs for it, it could be usable but most guitarists probably glue it to the Rock setting.

As has been mentioned it can be omitted but some claim it is part of the Dumble ODS tone.

I wire my Overdrive Deluxe amps with the Rock/Jazz switch, but I find that the amps tend to lose their openness in the Jazz position. Even tweaking the tone controls doenst regain the tonal balance. I always wondered why HAD incorporated this feature. Maybe it was to keep that Guitar/Mic switch that some of the very early amps had.

[Charlie Wilson]

Check out this demo (https://youtu.be/ap6odoC4itw) and note the amp settings; appears the J/R switch is in the 'jazz' setting.

I use the 'jazz' setting and like it, but it definitely requires a significant change to the tone stack settings - at least for me.

-jack

The question I have about this clip is, is it in Jazz mode or a third position PAB mode? It looks like the bright switch is also in the middle. It just sounds pretty gainy for jazz mode. Notice also that the mid switch is on and the master is pretty low.
CW

[Long Distance Call]

At 0:50 seconds into the video, he switches from Jazz to Rock and then back again. It sure looks like it's a single throw switch...
LDC

https://www.youtube.com/watch?v=ap6odoC ... e=youtu.be

[Structo]

His Rock/Jazz switch seems pretty subtle to me.

Mine is much more pronounced, but he does turn his guitar volume up and down throughout the video so maybe if the guitar signal isn't very strong, it makes less difference between the two settings.

[Aaron]

Mine has a big volume difference, but not as much with the deep switch engaged.

[Long Distance Call]

He has the mid boost engaged the whole time. At 0.50 he switches from Jazz to Rock. At 0.57 he switches from Rock back to Jazz and starts to reach for the Mid boost switch but hesitates and leaves it alone. The Mid boost being on all the time might account for the less drastic volume difference.
LDC

[ayan]

I always wired the J/R switch and not once have I found any use for it after 15 years! The early Dumbles had it labeled as a Guitar/mic switch, Gary. 😀

Gil

Yes, it is normal for the Jazz setting to be attenuated and cuts the top end.

I suppose if you re-adjust the knobs for it, it could be usable but most guitarists probably glue it to the Rock setting.

As has been mentioned it can be omitted but some claim it is part of the Dumble ODS tone.

I wire my Overdrive Deluxe amps with the Rock/Jazz switch, but I find that the amps tend to lose their openness in the Jazz position. Even tweaking the tone controls doenst regain the tonal balance. I always wondered why HAD incorporated this feature. Maybe it was to keep that Guitar/Mic switch that some of the very early amps had.

[bluesfendermanblues]

+1 have hardwired in rock position and put in a deep switch instead ....never missed the J/R switch, but never use the bright, mid or deep either.