MP-1 tone section

[DorsetRatt]

Probleem here is that the tc9170 only has 13 steps, -6 - 0 - 6 so no change possible.

That's a shame, but it was worth asking. I kinda like the current frequency centers and filter bandwidths, it's just that extra bit of fine tuning would be really useful, hence the idea of increments of 1.

Here's a mad idea ... could 2 x tc9170's be used together, so you would get 26 steps?

[Kim]

I really liked the adjustable Bass pot that the MOD3.666 came with.  IMO, that's probably something that should be a part of every Tone Mod for the MP-1.  A pot that can be adjusted without unracking and opening the MP-1 would be even better.

[MarshallJMP]

Ah yes you can alter the freq of the bass,ranging from 320 to 160 Hz.The MP-2 has a quite different filter,how would compare them?

[Kim]

Ah yes you can alter the freq of the bass,ranging from 320 to 160 Hz.The MP-2 has a quite different filter,how would compare them?

The MP-2 has the help of a Graphic EQ, which is a different thing altogether that helps the MP-2.  But the MP-1 always was problematic (for me) to get the right kind of "thump" from it.  The mids and higher felt right (to me) for most things but the Bass freq never seemed to sit right.  Being able to alter the freq of the Bass to suit the particular cabs used allowed the user to find one of the resonance freqs in the cab and then adjust the Bass on the front panel to compliment it. 
Having a Graphic EQ does help, but it's not quite the same as having user-sweepable freqs to adjust.

Just for comparison sake, here's the Parameters from the Rocktron ProGAP preamp:

Adjustable Parameters (with 64 incremented positions each)

• 1LEVEL     predistortion EQ level            -15dB to +15dB
• 1FREQ      predistortion EQ frequency     450Hz to 3.25KHz
• GAIN        gain level                            0 (0dB), 0.5dB to 70dB
• BASS        bass level                          -18dB to +18dB
• 2LEVEL     postdistortion EQ level         -12dB to +12dB
• 2FREQ      postdistortion EQ frequency    600Hz to 8KHz
• TREBLE     treble level                          -15dB to +15dB
• HUSH       HUSH threshold level             -70dB to 0dB
• OUTLEV     output level                        -70dB to +10dB

There's 2 sweepable frequency parameters in there that overlap, one for pre Gain and one for post Gain neither of which are "bass specific" but do help find the freq you want to adjust.

[vansinn]

It's been a looooong time since my MP-1 days; however, I always find 4-band stacks too limiting.

What I would prefer in most processors would be a 6-band stack, placed right after the preamp section:

a lo-lo, centered at around 70 Hz or so, partly for handling dives, partly for use with 7/8/9 stringers
a bass, with programmable center and gain
a mid, likewise with center and pain, but having a higher Q / narrower bandwidth when lifting it above, say, +6, to better accentuate those defining mids
ordinary high and presence
an additional 6-7 kHz filter, to be used for 'fizz-off' on distortions, and for lifting the upper harmonics for cleans

Now, this weren't what you [MJMP] asked about. So for the MP-1, as I remember it, the tonestack worked fairly well.
Keep the presence and high filter as-is, and just see if you can add my above mid- and bass ideas.
That is, those would be my ideas, of course. YMMV, as usual..

A note on the MP-2: While the extra 1/3rd octave EQ is nice, at times I really find it somewhat annoying fiddling around with all 13 EQ frequencies.
Well-laid-out voicings combined with afore mentioned 6-band stack ought to be enough.

[MarshallJMP]

The bass control has quite a big bandwith from 10 to 300Hz and after that it slopes on 6dB/octave.Maybe i'll start here and make a bandpass filter as opposed to a low pass.
A center freq of  80 Hz and smaller bandwith,maybe 20Hz above and below 80Hz.