Crumar Mojo 61 Review - (LONG)

[NTL2009]

RE - the FC-7 foot pedal...

 

It's not the 10K vs 50K pot value. The problem resides in how the pot is scanned inside the pedal along its 270 degree rotation. The Crumar pedal (that is actually made by Fatar) scans almost the whole range, leaving only a 10% at the edges that is compensated by the software; the Yamaha FC-7 is one of the very few pedals that is able to scan the whole range or most of it. Other pedals scan only a small part of the range, and since there are dozens of them, we can't support them all so we only support our Crumar branded pedal officially, and a few others non officially, one of which is the FC-7.

 

On the other hand, the FC-7 tends to wear out pretty rapidly, ...

 

I'm not sure if you're completely aware as to how an expression pedal works in a digital keyboard... Its resistance value is applied to a fixed voltage so the pot functions as a variable voltage divider, ...

 

I just placed my order for a Mojo61 with Sweetwater (after Guido answered some detail-level queries from me at the Crumar site), and I recalled this thread, and went to check the pedal from my DX-7, expecting it to be an FC-7. Well, mine is an early S/N DX-7, and I saw some vague note on the web about the pedal needed an upgrade from Yamaha to work with newer models. No details though.

 

So I checked the R values, and thought I saw 20K from tip to sleeve, but no, it was ~ 20 OHMS (not K-Ohms). Hmmm? And Megohms from Ring to anything else. OK, I think I know what's going on, so I open it up a little to take a peek. Yep, looks like the 20 Ohms is a light bulb, and the Megohms is a photocell, and the pedal moves a 'shutter' between them. But the photo-cell is only wired from tip-ring, so that might not provide the voltage divider that most inputs would be looking for, and I'm sure they won't drive a 20 OHM light bulb!

 

So off to buy an FC-7 tomorrow.

 

But once I can get some time with, and some measurements on the Mojo61, I might be able to replace the light bulb in that pedal with an LED (if the circuit will drive a few milliamps source - or use an external supply for the LED, but that's a bit awkward), and arrange the photocell to provide a full voltage sweep. I did a repair like this on my 1970's Yamaha Electone organ a year ago - the light bulb had burned out, so I wired up an LED to replace it (the bulb wasn't a common one).

 

The nice thing about an LED and photocell is it stays smooth forever - no pot wiper wear. Too bad this design isn't more common, but I guess you can't count on different instruments that supply the voltage to a ~ 10K pot to light an LED, though I bet most would with no problem. Some schematics I saw for the DX-7 look like they drive that bulb with a constant current source, but I need to look closer. But I'll proceed with caution, wouldn't want to risk anything on my new Mojo!

 

-NTL2009

[MoodyBluesKeys]

Many of the later Hammond organs used a similar system, with a 28 volt bulb driven by 12 volts. The bulb lighted dimly, and lasted a long time. Primary thing needed for light source is steady amount (although light color/frequency may be a problem with LED).

The original B3 method of expression uses a variable capacitor in a very high impedance circuit that passes more when fully meshed. OK in the tube era, not so much for solid state stuff.

 

The lamp will only measure 20 ohms when cold, incandescent bulbs increase in resistance quite a bit as they get hot enough to emit light. Might help to try different colors of LED to see which provides the best photocell sensitivity. IIRC, the photocell operated as a variable resistor depending on how much light was on it.

If you are concerned with drawing too much current from the Mojo, a small separate power supply might be used for the light source.

 

[aellison62]

Just brought my Mojo 61 home from Sweetwater yesterday and after unboxing and giving it a quick test drive I was wondering two things.

 

1. Out of the box, the default settings on the Leslie Sim were not to my liking. Most noticeable was a very quick horn ramp down that seemed unrealistic.I have read many posts in this thread raving about the Leslie Sim on the Mojo 61 and I was wondering how people have tweaked theirs to get what they think is optimal. I saw on the editor that horn ramp up and down and rotor ramp up and down were all defaulted to value 64 ( middle of range) Obviously, there is a lot of customization opportunity and thats great. Can anyone share what settings they like?

 

2. I assume my unit is running the latest firmware version but how ( where ) can I check? On the editor? What is the latest version # ?

[Delaware Dave]

A quick ramp up/down of the horn is akin to a real leslie. It's the drum that takes up to 8 seconds to fully ramp up and ramp down due to its weight. Guido simply set it to mimic the leslie that is in his studio. You might not be used to a real leslie because often leslie sims don't get it correct, but he did. However the adjustments are there for your correction and to get to your liking.

[Mitch Towne]

On the editor, look at the bottom of the first page. See if it is 1.31

[mate stubb]

A quick ramp up/down of the horn is akin to a real leslie. It's the drum that takes up to 8 seconds to fully ramp up and ramp down due to its weight. Guido simply set it to mimic the leslie that is in his studio. You might not be used to a real leslie because often leslie sims don't get it correct, but he did. However the adjustments are there for your correction and to get to your liking.

 

I like a slower horn acceleration, in fact I demand it even with my real leslies - the drama lies in the speed transitions. On a real leslie, you have to lessen the horn belt tightness, which I do by lessening the idler pulley spring tension.

[aellison62]

Yes, I am on 1.31 so good there, thanks. Ill probably slow the horn ramp a little bit, but thats just my preference.

[NTL2009]

Just brought my Mojo 61 home from Sweetwater yesterday and after unboxing and giving it a quick test drive I was wondering two things.

 

1. Out of the box, the default settings on the Leslie Sim were not to my liking. Most noticeable was a very quick horn ramp down that seemed unrealistic.I have read many posts in this thread raving about the Leslie Sim on the Mojo 61 and I was wondering how people have tweaked theirs to get what they think is optimal. I saw on the editor that horn ramp up and down and rotor ramp up and down were all defaulted to value 64 ( middle of range) Obviously, there is a lot of customization opportunity and thats great. Can anyone share what settings they like? ....

 

Welcome to the club! I received my Mojo61 from Sweetwater on Wednesday, and as expected based on reviews here, I've been having a lot of fun with it.

 

I have not dug into setting too much yet, I took some time to get it set up in a rack with my old DX-7 on MIDI ch#2 as the lower keyboard, and my converted 25 note pedal board on MIDI ch#3 ( I'll update that thread a little later - ( www.organforum.com/forums/showthread.php?53260-Convert-old-25-note-pedalboard-to-MIDI ).

 

But my first impressions include the feeling that while the default settings are very likely representative of a typical B3, they may not be what we prefer. So yes, it's great that these are user adjustable.

 

I agree with the some others, a slower roll up/down of the speed adds more interest to the rotary - it's the change that brings in the 'drama', IMO. Even the max settings don't seem extreme to me. I also found the top octave and a-half a little shrill, which is very speaker/amp/ear/room dependent, and I tend to adjust by riding the sell pedal anyhow, but I found adjusting the horn EQ down to ~ 32 seems to tame that. I need to spend more time with it to see if that's where I'll end up.

 

I played a bit with the demo download to get my feet wet with it before I committed, and the other thing I found to be just "too much" in both that demo and the Mojo61 for my liking was the cross-talk. At level 64, it seems to introduce what sound like 'artefacts' to me. It's probably authentic, but dropping it to 32 just sounded better to me. I suppose going to zero would rob it of some 'life'?

 

I also would like to hear from others as to their set-ups, like the different organ years that are modelled, etc (yes, I need to re-read this thread, probably a few things I missed). People will have different opinions/preferences, but it would be good to be aware of what people think affects what aspect of the sound, so we can each try it for ourselves.

 

Before I bought, I had emailed Guido at the Crumar site to confirm that the swell pedal performed an EQ (loudness) function, and Guido said it models the B3. Some said they never noticed it, but I found it very evident - if I have the volume high, but playing softly (with the pedal nearly closed), the bass pedals are quite 'heavy', but if I lower the volume so I'm pushing the swell a bit more, it's a nice effect. Feels great when you are in the right 'zone', IMO.

 

Here's something I just nailed down - is it a 'bug' or do the real oil & wood & glass Tone Wheels work this way? When I play the pedals with the 16' drawbar, or the bottom octave of the keyboard with 16' fold-back turned OFF, the volume increases significantly (6-12dB?) on that lower octave. I repeated this with my other MIDI devices disconnected and re-booting the Mojo,and it still did it (again, if you don't use bass pedals, you will need 16' fold-back OFF to hear this). Anyone else see this, or know if B3's are like this (I sure wouldn't think so, it's quite distracting)? But I wanted to check before sending Crumar a question on this.

 

 

Re - an optical sensing swell pedal:

Many of the later Hammond organs used a similar system, with a 28 volt bulb driven by 12 volts. The bulb lighted dimly, and lasted a long time. Primary thing needed for light source is steady amount (although light color/frequency may be a problem with LED).

The original B3 method of expression uses a variable capacitor in a very high impedance circuit that passes more when fully meshed. OK in the tube era, not so much for solid state stuff.

 

The lamp will only measure 20 ohms when cold, incandescent bulbs increase in resistance quite a bit as they get hot enough to emit light. Might help to try different colors of LED to see which provides the best photocell sensitivity. IIRC, the photocell operated as a variable resistor depending on how much light was on it.

If you are concerned with drawing too much current from the Mojo, a small separate power supply might be used for the light source.

Right, and a light bulb will have ~ 10x the resistance lit as it does cold, but since they run them at lower voltages for long life, maybe ~ 5x? So the 20 Ohm bulb would be maybe ~ 100 Ohm load? Well, I measured my Mojo61 today, it provides 5.2V to the pedal voltage divider. And a 10K Ohm pedal dropped it to 4.7V, and 1K Ohm load dropped it to 2.6V (likely a 1 K Ohm R internal for short circuit protection). A 2.2K Ohm and a white (3V) LED was still pretty bright (0.8 mA), and dropped the Voltage to 4.4V. Not sure that brightness would be enough to drive a photocell low enough, and 4.4 V out might limit the top volume a bit, so yeah, and external power supply is probably the way to go. But since I have my FC-7 now, I probably won't look at that for a while, but since I'll likely mount my swell pedal to my pedal board, an external supply would be easy.

[Jazz+]

Crosstalk, do we like it set at 64 in the Mojo? Is it really useful?

[Adan]

Got my Mojo 61 yesterday. The story of why I got one is as follows. I realized given my playing situation that I wanted a dedicated clone, spent a lot of time trying to decide between the Legend and the Mojo. When the Crumar Seven was announced I got excited about that and ordered one, but canceled the order when I realized a clonewheel would do me a lot more good right now.

 

Between the Legend and the Mojo it's a tough decision if you haven't played either of them. What tipped me towards the Mojo was the optional lower manual, which I will want only sometimes. That, and the included EPs make a powerful argument for the Mojo even if everything else is assumed to be more or less equal.

 

So far, after a few hours with it, I'm very happy. There's been a lot of comments about the action on the Mojo and I agree it's very nice, perhaps a little more B3-like than the more firmly sprung Electro and SK1's I've played. I can see why some folks prefer the action of the Mojo but I can also see it as simply a matter of preference.

 

Bottom line, I foresee a long relationship with the Mojo.

 

The one thing that jumps out at me that I wish it had would be something like a button to cycle between a handful of snapshots. I feel like that would go a long way towards making the Mojo more useful even when you don't want to bring a Wi-Fi device. The device should work well most of the time, but I see it as a weak link in the operational setup, something you don't want to rely on too much in case it fails.

[Jazz+]

Congratulation! The action is superior. And the C3 and Percussion are great. 888000000 sounds more authentic to me than Hammond SK which I owned previously. The Rhodes and Wurlitzer are so good there is no contest. The AP is the only so so..,

 

I love the convenience of having the easy to use editor in my iPhone. I don't think I need to cycle through snap shots as you mentioned. All the essential sound control knobs are right on the main control panel.

[Jazz+]

By the way I have switched from 65 B3 to the Mitch Towne 65 A100 MT it has better balance across the range for the top 3 octaves and more presence. All of the other editor settings are at default values except I did reduce the Roland RD Chorus balance for the EPs to a more subtle level.

[Adan]

Jazz+, I agree about the C3, percussion, and 888. Those things, plus a realistic click, are 95% of what I care about and the Mojo does it better than anything I've laid hands on.

 

Oh, and the leslie sim is the best I've heard. I ordered a neo-vent II with it thinking I might need that. A-B'd with the Mojo's sim I'll just be sending the vent back. The Mojo's sim is better.

 

My only point about the snapshots was, what if your iPhone battery dies because you had a long text chat on the way to the gig and you forgot your charge cord, etc . . . stuff that's not supposed to happen but that sometimes does. I feel like I could do almost everything I would want to at a gig with 3 or 4 snapshots.

[Jazz+]

What internal settings do you need to change at a gig? I have it optimized already

[Adan]

What internal settings do you need to change at a gig? I have it optimized already

 

The main thing that comes to mind is different effects on the EPs. I'm probably all set with one organ snapshot.

[Jazz+]

You can simply hold an effect button for 2 seconds each time you want to cycle to a different effect. There are 2 effect buttons. How many effects do you need when you play Rhodes? I use 2 at most: Chorus and maybe Wah wah with pedal (rarely) or mono Vibrato (rarely). Tip: use the JC amp sim if you sometimes need a bass boost like on real Rhodes. The default amp sim is a Fender Twin Reverb which makes it sound thinner, opposite of a bass boost.

[NTL2009]

Crosstalk, do we like it set at 64 in the Mojo? Is it really useful?

 

I mentioned it in my post just before yours:

 

... the other thing I found to be just "too much" in both that demo and the Mojo61 for my liking was the cross-talk. At level 64, it seems to introduce what sound like 'artefacts' to me. It's probably authentic, but dropping it to 32 just sounded better to me. I suppose going to zero would rob it of some 'life'?

 

Well, I've had a little more time with it, and I was noticing some odd low-level bass rumble/distortion at times. Experimenting, I can most easily duplicate it by playing a chord in the top octave with the first 3-4 drawbars pulled out, and the volume knob high so that the swell pedal is near all the way pulled back (soft), and it will be more evident with the bass/EQ knob turned up. Hear it? The pedal is accentuating the bass compared to midrange at this point, so that adds to hearing the 'noise'.

 

So more experimentation in the editor - the bass rumble sounds are definitely reduced by reducing crosstalk setting, and I ended up with it all the way at 000 for now. And the "Xtalk Shape" setting seems to lean towards the bass at 000, and towards the treble at 127, so I set that at 127 (it had a slight effect, even with Crosstalk at 000).

 

I moved the leakage down to ~ 010 as well.

 

Much better to my ears. It also helps to keep the bass EQ down, and boost the drawbars if needed.

 

Is "crosstalk" really supposed to serve up these low, random rumbles? They just don't sound right to me. Am I missing something by keeping crosstalk so low? Maybe, but I find that rumble distracting.

 

Anyone else notice this with Crosstalk?

 

edit/add: I wonder if this could be related to what I also posted above - that the 16' drawbar sees to be at a very high volume in the bottom octave (on pedals, or on keys with 16' foldback turned OFF). Maybe this is just too high, and therefore coming through to much in the crosstalk?

[aellison62]

To me, the Crosstalk gives the authentic "growl" from a B3 tonewheel organ. It is precisely what separates a great clone from a mediocre one. IMHO, reducing the Crosstalk to 000 is taking away from the character in a bad way.

[HammondDave]

To me, the Crosstalk gives the authentic "growl" from a B3 tonewheel organ. It is precisely what separates a great clone from a mediocre one. IMHO, reducing the Crosstalk to 000 is taking away from the character in a bad way.

 

Agreed! Crosstalk is everything to the growl.

[NTL2009]

To me, the Crosstalk gives the authentic "growl" from a B3 tonewheel organ. It is precisely what separates a great clone from a mediocre one. IMHO, reducing the Crosstalk to 000 is taking away from the character in a bad way.

 

Agreed! Crosstalk is everything to the growl.

 

Thanks for the feedback. Well, I figure they include it for a reason! But it just sounds 'off' to me, hmmmm.

 

So some more experimenting, and I found another interaction. The low rumbling I hear is greatly reduced when I select "Complex Wheels ON". When I do that, and also set "XTALK SHAPE" to 127 (more treble crosstalk than bass), I can hear a pleasing sort of fuzzy modulation in the midrange of the keyboard, and I even like it now with pretty high levels of crosstalk (80-90's). I still get a little rumble with a chord in the top octave, but much, much less noticeable. If I go back and turn Complex Wheels OFF again, the rumble comes back strong enough to be a distraction.

 

Another clue - with COMPLEX WHEELS ON, I also don't get the big bass boost in the bottom octave that I mentioned earlier (and this is not a gradual increase, it is binary, the B is like 2x as loud as the C right above it) that I got with COMPLEX WHEELS OFF. I bet this is related, those heavy bass tones are creating a lot more crosstalk as well.

 

With COMPLEX WHEELS ON and (for my prefs), XTALK Shape = 127, then mid-to-high levels of Crosstalk sound good to me.

 

Can anyone else replicate this by turning COMPLEX WHEELS OFF? I think I have enough info to send a bug report to Guido at Crumar. The Complex Wheels OFF is just far too loud on the 16' drawbar on pedals, or on keys with 16' foldback OFF.

 

 

 

 

[Adan]

You can simply hold an effect button for 2 seconds each time you want to cycle to a different effect. There are 2 effect buttons.

 

I missed that the first time through the manual but yes, I see that is how it works. Which means I can gig without an editor no problem.

[NTL2009]

... with COMPLEX WHEELS ON, I also don't get the big bass boost in the bottom octave that I mentioned earlier (and this is not a gradual increase, it is binary, the B is like 2x as loud as the C right above it) that I got with COMPLEX WHEELS OFF. ...

 

I verified this with an o'scope, the bottom octave with 16' foldback OFF stays pretty even with the COMPLEX WHEEL ON. But with COMPLEX WHEEL OFF, the voltage jumps to over 3x right at the octave break. Sure seems like a bug, and probably easily overlooked as not too many people run with 16' foldback OFF, or run bass pedals with COMPLEX WHEEL OFF.

 

 

[mate stubb]

Not a bug.

 

When you turn complex wheels off, you replace them with the 16' pedal tonewheels. They are balanced for extra bass, and getting that extra bass is the reason you do that in the first place. Not authentic to a B-3, but to the earlier consoles without selective vibrato.

[Jazz+]

Maybe stop listening with headphones or high definition studio monitors. The Mojo is set up to sound like the real thing, great for live playing. Trust the sound designer. They put those sounds there for a reason. It is not supposed to be some sort perfect clean audio image of an organ sound.

[NTL2009]

Not a bug.

 

When you turn complex wheels off, you replace them with the 16' pedal tonewheels. They are balanced for extra bass, and getting that extra bass is the reason you do that in the first place. Not authentic to a B-3, but to the earlier consoles without selective vibrato.

 

Interesting. But is this really how it is implemented on a real Hammond TW? I always thought the 'complex' wheels' were just a way to get more harmonics in the pedals w/o requiring more drawbars, a reasonable and clever approach. Why boost the bass so much - that's what drawbars are for? And regardless, the setting is really unusable with a 25 note pedal board because of the sudden jump in level in the bottom octave (again, this isn't a curve or transition - the level jumps suddenly going down one semi-tone from C to B). If you do a descending run from the top octave of the pedals, down to the lower octave, the volume shift is jarring.

 

Even if this was on spinets with 13 notes pedals (or were they an octave and a half?), you'g that discontinuous jump in volume - it just doesn't seem right to me.

 

For now I'm using the complex wheels, and they sound nice, but sometimes I like the pure round sound of some 16' and 8' sine-wave-ish, flute-ish pure foundation tone. But between the volume jump, and the effect on Crosstalk, I really can't use this option.

 

 

Maybe stop listening with headphones or high definition monitors. The Mojo is set up to sound like the real thing, great for live playing. Trust the sound designer. They put those sounds there for a reason. It is not supposed to be some sort perfect clean audio image of an organ sound.

 

Yes, I'm using some high def monitors and a fairly clean amp, in a quiet room, and I'm not competing with a drummer or guitar slinger, and sometimes using headphones, so this can make 'grunge' stand out far more. I'm of two thoughts on this:

 

A) If this truly represents a real TW, then yes, it should be there. Though I'm skeptical that this huge and sudden shift in bass level is authentic, and it's a large part of what is causing Crosstalk to go from adding a pleasing, interesting, complex/noise/modulation to the tone, to producing a distracting rumble in a top octave chord.

 

B) Many Hammonds were used in quiet home settings, so a replica should be pleasing in that setting as well. And since this is modern times, and we can edit these parameters, it would be nice (and I would think good marketing) to provide enough range to reduce some of these if they come across too extreme for some listening with clean monitors and/or headphones.

 

And on the opposite end of that scale, I find myself often cranking the 'click' setting to the high end for some playing, and might even like it to go to 11 (or 127?) - I swear some of those jazz recordings have a LOT of key click in them, more than I can get. And it's a nice effect (occasionally), and also nice to be able to take it zero for other playing. So it's not always about 'clean'.

 

I'd really appreciate it if someone could duplicate these settings and report here: COMPLEX WHEELS OFF, XTALK SHAPE near middle or near 000, and CROSSTALK near the middle (or higher if that's you normal pref). Play a chord in the top octave - is that really what you want to hear? It is further accentuated with some bass boost, and/or at low swell pedal volume (swell EQ boosts bass as well).

 

I'm not sure high-def monitors will be an issue here, I would think that rumble will come through on just about any speaker with the kind of bass response you use with a keyboard.

[Mitch Towne]

What tonewheel set are you using?

[NTL2009]

What tonewheel set are you using?

 

I hadn't noticed much difference, so I went back just now to give you a more specific answer. I'd say the 'rumbling' is essentially the same across all the tonewheel sets, though any of them that are brighter in that top octave will mask it a bit, just due to the relative volumes. But if I focused on the rumble itself, it didn't seem to change.

 

These settings, (COMPLEX WHEELS OFF, XTALK SHAPE 000, CROSSTALK 127) should make it more (very, IMO) apparent, then you know what to listen for (or maybe you don't, you might not be able to ignore it once you do! ). A Low swell pedal, and bass EQ boost will bring it out even more.

 

The bottom octave boost of the COMPLEX WHEELS OFF seems consistent across all the tonewheel sets also.

[Jazz+]

I think I hear what you are talking about when I play a C triad in the top octave. There is a background mechanical hum sort sound. Sounds like soft subtle wind outside. Isnt it the crosstalk effect? I dont mind it when I play single notes up there, it adds girth. The thing is I never play 3 note sustained chords in the top octave. When is that ever sounding good ? I never do it on a Rhodes or real piano either for that matter. Chords are nice in the middle range. The top octave is for single notes percussive stuff. Or two notes at most, nothing smaller than a fourth.

[Jazz+]

You are right, I notice the lowest bass octave does have have a boost compared to the next octave up.

[Jazz+]

Hopefully that lowest octave can be volume leveled in an update.