#1
Hi all!

I've recently acquired a Vox AC 30 CC2 Head, and use the Top Boost channel with my Marshall TSL100 for distorted sounds, and the normal channel for clean sounds, with a Lehle AB splitter in front. As many of you will have guessed, this causes a slight dip in volume when channel changing.

I was just wondering, would i be able to use a line driver or signal boost of some description after the AB on the clean side, but before the normal input on the AC30 in order to increase the volume of the normal channel? If so, which booster would you guys recommend?

My first post by the way, so hello! And apologies if there is some obvious reason why i cannot do this which i've missed.

Many thanks,
Aled
#2
Can't you just increase the channel volume on the Normal channel? A booster in front will do the same thing, so if you are out of headroom with the channel volume, then a boost isn't going to fix the problem. If anything, you'd want a gain boost in front of the TB channel, if you have to have the Master high for the normal channel headroom.

You can put a boost after the A/B, but it might introduce phase or ground loop issues if you're not careful. Usually you can match channel volumes just fine with some attention to the master volume.
#3
I've got a nice amount of crunch gain wise which is why i don't want to increase the channel volume. I'm really looking for a way to increase the output volume of the normal channel without increasing the gain or affecting the volume of the top boost channel (which now i've said it sounds a bit like an impossible task as any booster would just increase the gain i think)
#4
I don't know if I understand. To increase the normal channel volume without affecting the top boost channel volume, all you have to do is turn up the volume on the normal channel.

If that results in too much gain on the normal channel, raise the master volume and lower the TB channel volume. Then if there's not enough gain on the TB channel, think about an overdrive in front of the TB channel.
#5
The other issue i've got is that i'm trying to avoid increasing the overall volume of the amplifier as well. The Top Boost sounds perfect, and is at a perfect overall volume, and I run a Boss SD 1 and MXR Badass Overdrive in front of the amp. I'm just trying to increase the overall output of the normal channel without increasing the volume of the top boost. I know that this is a major flaw in the AC30 (the lack of two master volumes), but i wasn't sure if there was a way round it.

At louder volumes though, i think your suggestion would be spot on
#6
Ok, so I can assume that you've tried raising the master volume and lowering the TB channel volume? That's how you would avoid increasing the overall volume.

The whole trick with the AC30 channel switching is to find the master volume setting that covers the volume you want your clean channel and then the volume you want for your dirty channel. If you run one channel with a dirt pedal in front of it and on all the time, this should be easy. If you're expecting to run one channel super hot and turn the master down, you have to expect the other channel to do largely the same, and there's no pedal that is going to add clean volume to the already overdriven normal channel.