Moog Music Forum

Which one of these is better to be used for synths and why?

There are two major differences between the two.
1) The lowest frequency filter on the 105B is a shelving (low-pass) type, whereas the 105 has a band pass filter. This means much more bass will come through on the Bass MuRF.
2) The two units have different rhythm patterns. You could possibly say that the 105B has patterns more suited to bass, as they are more "groovy" than the MuRF. But that is subjective.
So, why not get both ?

latigid on wrote:There are two major differences between the two.
1) The lowest frequency filter on the 105B is a shelving (low-pass) type, whereas the 105 has a band pass filter. This means much more bass will come through on the Bass MuRF.
2) The two units have different rhythm patterns. You could possibly say that the 105B has patterns more suited to bass, as they are more "groovy" than the MuRF. But that is subjective.
So, why not get both ?

how does the high end come through on the 105b? since the cut freq starts much lower on the 105b i've wondered if it would be worth it for anything other than basses.

I guess because there are a bank of filters, the highs still come though on the B, it just depends on which one is active.

(The only difference is the lowest filter, but check the manual to be sure.)

I know this doesn't answer your question, but I use the 105 with my Voyager, and it is simply amazing. It is permanently a part of my setup. I use the mixer control as my "bypass." Sometimes I turn off the animation and use the 105 as a fixed filter bank. The mix control is very useful for dialing in the right sound. The 105 really makes a difference to my setup. I would say if you are using your synth for bass, then get the 105B. If you are using your synth for general use, then the 105.

The highest filter's frequency on the MuRF is 3.4K while the highest frequency on the Bass MuRF is 1.8K, almost an octave lower. All of the frequencies on the BMuRF are shifted down.

Cheers Oyster. I guess I was thinking the BMuRF goes:

LP BP BP BP BP BP BP BP

and the MuRF goes:

BP BP BP BP BP BP BP BP

Glad somebody checked the manual, oftentimes they answer ALL the questions you have. Perhaps a manuals section on MS?

so, if one wanted to let more bass through on a standard MF105MuRF, could it be modified (relatively) easily by swapping out a resistor on one of the filters for another resistor of a different value or something? or would that be a much more complicated modification?

If you like, you can back off the Mix control to let a bit more bass through, but this might not be what you want. (I personally (usually) like my effects quite full-on.)

Wouldn't it be great to mod the MuRF so you could control both the filter band's gain (with the slider) and it's cutoff frequency (via a new pot sitting above each slider)?

In my opinion the Bass Murf is wonderful for keyboards, too. Anything with enough power concerning the treble area of a sound fits perfectly.

I much prefer the Bass Murf in combination with an old string ensemble to the "normal" Murf.

An ARP Omni or a solina through a Bass Murf is one of my standart setups. This even gives more "shine" to a sound than anything else. Just set the amount of the Bass Murf to 3-4, so that the original signal is still more dominant. Try it out !

latigid on wrote:Wouldn't it be great to mod the MuRF so you could control both the filter band's gain (with the slider) and it's cutoff frequency (via a new pot sitting above each slider)?

Yeah, and it'd be neat to adjust all the filters' resonance Q as well... I'd settle for swapping out the value of just one of them, though.

Is this possible? I guess I should review some DIY filter schematics.. seems like one could mod in a pot, or a different fixed cutoff freq value somehow.