Amp mod advice needed

Hi all

I’ve recently bought an amp with a single input, my last amp was an AC30 with a High and Low input.

I was using the low input with my 335 with humbuckers, having moved to the new amp I’m finding that I’m struggling a little bit for headroom and missing the option of a low input for a bit less gain. 

Turn the guitar volume down to about 7 or 8.

Or if that doesn’t work with how you use the guitar controls, make a short male-to-female cable extension with the two resistors in the plug.

Thanks 

ecc83 said:

Don't want to be rude Kier but does the 335 not have a volume pot?

Ha! An attenuator switch is beer into water technically if you are up to the drilling and soldering but why not just buy a small die-caste box and fit two jacks in it with 10dB or so attenuation? That way you keep the amp pristine and original.

Dave.

Thanks Dave - it does indeed and I know that’s an option. I suppose I could compensate the gain on any drive pedals, it’s just a different way of working than I’m used to with the AC30. 

A passive box with two 68k resistors would be easy, even easier to build it into the cable assembly.

Turning down the guitar volume often looses top end or you have to put up with some bright cap arrangement.

An EQ pedal set to cut would also get you there quickly and you could use it to tweak the EQ so you don't have to adjust the amp for different guitars.

Clean boost pedal with the gain turned down a few db from unity.

There is a difference between using a 68K+68K resistor divider like the classic two-input amp arrangement, and a clean boost or EQ pedal turned down - the lower total input resistance (136K) compared to the normal 1M input impedance will noticeably soften/dull the tone, as well as halving the signal level. It's also not the same as turning down the treble or the highs on a graphic EQ, since it changes the load on the pickup. Some people like this, in which case you need to do it with a passive divider - some don't, in which case an active solution or a much higher impedance divider is better.

what about this?

If you have a valve amp and V1 is a 12AX7 changing it to a 5751 pre amp tube may help.

PAL said:

If you have a valve amp and V1 is a 12AX7 changing it to a 5751 pre amp tube may help.

This is a good call, I did this with a CARR and it lowered the noise floor too. 

I have also been using a spark 4 knob boost into a 5e3 as an underdrive with the treble boosted and lower than unity volume. Hit it off to rawk.

Thanks for the advice everyone, I will try the under-drive / boost idea and also a 5751 valve. If that doesn’t float the boat I’ll see if I can fire up the soldering iron :)