Double Bass Bass Preamp with Graphic/Parametric EQ and Limiter

[garycsloan]

Hi all! I've been reading forums for years but just became q member. I recently bought a Markbass Mini CMD 121P to use with my Solo Revolution II and it is great. I really like my pickup but it has a lot of subaural frequencies and attack that tend to be really hard on speakers and I was able to curb this with the said features on my old amp.
A preamp with these features would be ideal due to being able to use it as a DI but I would be open to rack unit or foot pedal as well. Do you have any suggestions? Although I want to keep costs down I have a bigger budget than I will have for years since I just got my koan check from grad school at CU Boulder If I can find such a piece of equipment I think I will be set for years to come.

 

[Ric Vice]

Hi all! I've been reading forums for years but just became q member. I recently bought a Markbass Mini CMD 121P to use with my Solo Revolution II and it's great. I really like my pickup but it has a lot of infrasonic frequencies and an attack that tends to be really hard on speakers and I was able to curb this with the said features on my old amp.

A preamp with these features would be ideal due to being able to use it as a DI but I would be open to rack unit or foot pedal as well. Do you have any suggestions? Although I want to keep costs down I have a bigger budget than I will have for years since I just got my koan check from grad school at CU Boulder If I can find such a piece of equipment I think I will be set for years to come.

Gary,
Thanks to TB member Durb, we've all learned that what you're referring to is Infrasonics, which are usually eliminated by amp designers with low cut filters that are usually built into their bass amps, but not always. I'm surprised that the Markbass CMD 121P has an issue with this, since Markbass has such a solid reputation, as a bass amp manufacturer. Based on your pickup choice, I remember the Revolution Solo, as having lots,of low end, so I'd try changing out pickups before I purchased a new EQ box. If you think still need a preamp after that, an inexpensive and very well made box is the HPF Series 2.

Ric Vice

 

[vin*tone]

Yeah an FDeck HPF pre with the variable HPF frequency is a great investment.

I often use it for EB to tame an unruly stage as well.

 

[lorianb]

I picked up a pz-deluxe a few months back (http://www.tonebone.com/pzdeluxe.php) and it totally changed my outlook on amplified sound. The 10M ohm buffer is the key here. It took away the harsh attack and the hollow nasal sound of my Realist. Now, I get part of the well-rounded sound of my Shen 180 with the full somewhat nasally sound of the Realist. Very intuitive EQ if somewhat simple. Lo-cut can be useful depending on your bass, room, etc but the phase switches are especially useful. Setting up onstage, if you're getting resonant frequencies, kneel down, flip amp phase and boom, it's gone. If front of house is getting resonance of your DB, tell the soundman/woman to mute for a sec, switch phase on direct box and ask him/her to see if it helps. It usually does. It won't do everything you're looking for but it's close. Really smart people on here might be able to explain the 10M ohm buffer and why it works wonders (see link here : http://www.talkbass.com/threads/pickups-optimal-loading-not-impedance-matching.977348/ ) but I put off to black magic and carry on. Don't be putting out for limiting or compression 'til you've tried a suitably buffered pre with your set-up.​

 

[garycsloan]

Gary,
Thanks to TB member Durb, we've all learned that what you're referring to is Infrasonics, which are usually eliminated by amp designers with low cut filters that are usually built into their bass amps, but not always. I'm surprised that the Markbass CMD 121P has an issue with this, since Markbass has such a solid reputation, as a bass amp manufacturer. Based on your pickup choice, I remember the Revolution Solo, as having lots,of low end, so I'd try changing out pickups before I purchased a new EQ box. If you think still need a preamp after that, an inexpensive and very well made box is the HPF Series 2.

Ric Vice

Hi Ric, thanks for the response. The Markbass Combo Head II may very well have a low cut filter, I didn't realize amplifier makers usually include that. The specs for the head say that the frequency response is down to 40 hz so perhaps that is the cut off and my worry is based on past experience. Although I'm overall happy with the Markbass sound I miss the parametric EQ from the SWR SM400 I was using since I could easily locate the frequency for string scratch, fingerboard click, "thud" from my attack, feedback and room issues etc. I've found with the Markbass that the high mid knob pretty much controls how intense my attack is and it would be good to have an pre-amp that could help with that issue. I use the very basic 2-band Fishman preamp right now and it certainly helps but I would like more control and possibly an XLR out to use as a DI, an XLR in with phantom power would be a big plus as I'm considering using a mic instead of or in conjunction with the Revolution Solo pickup. I think you're right about trying other pickups, although I'm happy with it for the most part it has these issues. Here in CO the climate is very dry and the temperature can change 20 degrees from day to day so the action on my bass changes a whole lot. This has a huge effect on the sound of the Revolution Solo so some days I feel like I'm starting over in trying to set my EQ.