Hot Rod Deville, Frommel Supreme Mod, gain no switching with channels

[gsgtrman]

Good morning! I am new to the forum, from northern NJ. I have been running my own guitar repair shop for about 30 years, but I do not do amp work. I have done maintenance and mods successfully on my own Marshalls. My knowledge is very limited in electronics, but I solder very well and can read instructions. I am helping a friend and fellow guitarist install the Frommel Supreme mod on his Hot Rod Deville and followed this guide:

https://fromelelectronics.dozuki.com...+Kit/1?lang=en

I checked and double-checked all of my work. What is happening is that the gain does not change when I switch from Normal to Gain channels, but does when I switch from Gain to More Gain. The Gain channel does not have enough gain, it sounds like the normal channel, and the More Gain sounds like the less gain setting. Maybe even less than that. All controls do what they are supposed to when the channels change. For

Like I said earlier, I'm a guitar guy. I have no troubleshooting skills in this area, other than making sure my soldering is clean. I double-checked all components as they went in. i have two pics of my work, they're not great but are available here:

https://1drv.ms/u/s!AqX6QxKwmrSgcNwG...oG-ks?e=MsioLl

Frommel has been less than helpful, I have reached out several times via phone and email, but have gotten no response as of yet.

Any suggestions and insights are appreciated, thanks for taking the time to look.

[nosaj]

Get a second set of eyes to go over every step of the guide and double check the values. i cannot view the pics.
nosaj

[Helmholtz]

Do you have a schematic?

[glebert]

Did you do the Global Master Volume Mod? This sounds like what you are describing. Note: this is from their notes on the Deluxe kit, but assume it would act the same on a Deville.


Global Master Volume Mod (optional)
Our Global Master Volume Mod will allow the master volume control to work on both the clean channel and
the drive channel. It will also turn the drive channel into a second clean channel with a single selectable
boost stage. This mod will allow you to have total control over your volume and also allow you to drive your
clean channel at the volume control and dial back the overall volume with the newly functioning master vol-
ume control.
Note:
The yellow drive setting will be a clean channel and switching to the red (more drive) setting will de-
liver the drive the yellow setting originally provided.

[mikeydee77]

Did you do the Global Master Volume Mod? This sounds like what you are describing. Note: this is from their notes on the Deluxe kit, but assume it would act the same on a Deville.


Global Master Volume Mod (optional)
Our Global Master Volume Mod will allow the master volume control to work on both the clean channel and
the drive channel. It will also turn the drive channel into a second clean channel with a single selectable
boost stage. This mod will allow you to have total control over your volume and also allow you to drive your
clean channel at the volume control and dial back the overall volume with the newly functioning master vol-
ume control.
Note:
The yellow drive setting will be a clean channel and switching to the red (more drive) setting will de-
liver the drive the yellow setting originally provided.

That sounds like a really useful mod. The HR distortion channel is not popular with my clients. Do you have more details?

[glebert]

That sounds like a really useful mod. The HR distortion channel is not popular with my clients. Do you have more details?

Page 7

https://fromelelectronics.dozuki.com...anual-2020.pdf

From the pics it doesn't look like this mod was done by the OP, at least not intentionally.

[glebert]

From the OP pic it looks like C9 is not installed. The instructions in the first post don't show C9 being replaced, but on page 6 this set of instructions (https://fromelelectronics.dozuki.com...ferrer=wiki:47) say that you do replace C9 unless you are doing the Global MV Mod. Similar for relay K2. Without those it seems like there is no way that "More Drive" can really be engaged. I think the set of instructions in the original post basically don't correctly separate what mods are for the Global MV.

[gsgtrman]

Hey everyone - I'm sorry for the late response, very busy week and for some reason was not getting notifications of replies. I did not know what the outcome of the mod was to be, my buddy just brought over a box of supplied parts. I did hear from Frommel yesterday. It turns out that this mod did include the global MV mod and that the amp is doing exactly what it is supposed to now. Now that I know what the deal is, I must say the amp sounds really nice now. The Normal and Gain channels are very much classic Fender, while the More Gain setting has a hint of Marshall JMP.

Thanks so much for all of the replies, sorry to have wasted anyone's time on this.