Help with Parametric EQ

[Jkendrick]

I have a VFE Rocket EQ and I admit I don't fully understand how to use it. I have played with it enough that I have been able to shape my after OD tone to mostly where I like it. But I am still getting some muddiness in the lower notes. Can I use the EQ to specifically shape the tone of these notes without effecting the tone of higher notes? If so,  how? I want more clarity in those low notes.

[Heady Jam Fan]

Is your muddiness too much bass or is it mushy, inarticulate bass?

If its the former, I'd expect the EQ can help, but I've never used the VFE. However, there are two approaches I'd think might work...

First and simplest - turn down the bass knob. That shouldn't affect any other frequencies and might fix your issue IF it affects the frequencies that are causing your muddiness.

Second, you can use the parametric feature to cut some low-end for clarity. The parametric band ranges from 60hz to 6Khz. The frequency knob lets you set the frequency that you will boost or cut (with the mid knob). Since your problem is bass, we want to start with the frequency knob at the lower range (counter clockwise). Since we are cutting frequencies to clean up your bass, you want the mid knob below unity (probably below 12 o'clock). Set it so it noticeably, but not drastically, cuts a bit of volume at whatever frequency your frequency knob is set to. By sweeping your frequency knob back and forth, you can start to hear if you muddiness clears up at any particular point in the sweep. As you do this try adjusting the Q knob. Turning the Q knob counter clockwise lets you cut a narrower range of frequencies. I expect you want the cut the narrowest range of frequencies the smallest amount that lets you reduce the muddiness. Too narrow of a Q with too much cut (the low on the mid knob) will sound odd, and too wide of a Q might leave your tone sounding empty.

Other things could be pickup or pole-piece height, or something with the amp. Is this your deluxe? Deluxes, with 6V6's, don't have the more articulate bass. I personally find the bass a bit muddy in the Silverface circuit, and found converting my DR to Blackface specs really tightened up the low end. Additionally, old caps (or tubes) can make the amp really kinda 'lazy' sounding, so just make sure those aspects are up to date as well. Lastly, the location of the amp has a big effect. On carpet is probably the worst, on wood can over-accentuate the bass, on concrete can increase the treble... I keep my amp on top of my Pedaltrain Hardcase, which de-couples the amp from the floor and is a consistent medium for my amp every place I play. I think a chair is too tall and make the amp a bit bright and beamy. Other people have used wooden shipping palettes or crates of some sort. If you want to go all-out, look into the Auralex Gramma.

[Jkendrick]

Thanks for the very detailed response. This is my Silverface. I have the amp on the bottom portion of the roadcase. So it's sitting on foam but up from a carpeted floor on the casters. I posted a clip of me messing around with the isolated tracks from the PoN Llama in that thead but here it is again (don't mind the sloppy playing).

https://soundcloud.com/jim-kendrick/llama

What do you think of the tone on the lower notes? I feel like it's the latter of your descriptions: "mushy, inarticulate bass." I'm not sure I want to spend the money to Blackface the amp as i am just playing at home. I actually was auditioning for a band and had to bow out due to lack of time.

[Heady Jam Fan]

Oh yeah - it sounds mushy and inarticulate to me. Although I'm just listening on my laptop speakers (been away from home and I don't have my headphones). Its really hard to diagnose, so I'm kinda taking a shot in the dark - bringing the amp to your local guitar shop might be faster/easier...

What speaker is in there? If its old or has a really small magnet, that can be part of the issue.

So moving your amp around the room, into different rooms and onto different media (your foam / casters, etc) doesn't make a difference, then I might wonder about other things with the amp. Although the VFE EQ might fix it.

How old are you capacitors (inside the amp) and tubes? Is the amp biased (or has it been recently)?

If the electrolytic capacitors are all original, they might be the problem and need to be changed. They have a lifespan of about 10 years, so if they are original, they are likely hurting your sound. Especially the ones under the doghouse (metal thing on the bottom of the amp, which has HIGH VOLTAGE - BEWARE if you open it), and the one for the amps bias (inside the amp, closer to the lamp). The original ones in the doghouse were usually cardboard-like on the outside - if they are 'swollen' or leaking foamy/crystally stuff, they are BAD. There also capacitors at every stage of the amp that need to be replaced every decade or so - these ones are usually white on the outside. If you get the chance to carefully pull out the chassis from the cabinet, pictures can help to determine if your caps are old/original. If your caps are old and need to be replaces, its only a tiny bit more to have the amp tech blackface the amp, if you want.

Tube issues...
First, is the amp biased? If so, then are the tubes worn out? Its a good idea to have a set of backup tubes - you can determine if tubes are worn out by going through the amp, tube by tube, and swapping the old one for a new one and listening for improvements in tone. Of course, when you do this for the power tubes (6V6 tubes), change them both at the same time (and you need to bias the amp). The Phase Inverter (last preamp tube) and first preamp tube (V1 for the normal channel, V2 for the Vibrato channel) are the most likely culprits in preamp tube problems. The Phase Inverter gets pushed pretty hard, but the first preamp tube has the greatest effect on tone. If either of these tubes are beat and you use reverb, its a good idea to swap out the reverb tube IMO: its get run really really hard in a DR.