Got my GK MB Fusion today!!!!

[KJung]

Kjung and others, can you give some thoughts on how does this amp compare to the tecamp puma?

A lot less expensive!!!!! The Puma is unique, and while it does have a bit of that super extended low end and super extended treble of the GK MB's, it is much cleaner and more 'pure' sounding.... much less grind and aggressive. The low end of the Puma acually sounds bigger and warmer and more 'tubey' than the Fusion, and the top end is much more 'uber clean hi fi' than the grit of the Fusion up top.

I would think that those looking for that big, wide Puma tone would be reasonably happy with the MB500 more than the Fusion, but the MB500 is still much more 'in your face' than the Puma... the GK heads really are super voiced to me.... kind of a 'whoa' response when you first plug them in... that 'knife slice' top end and huge bottom, and that midrange distortion (i.e., that bit of grit built into the voicing of the amp). Again, kind of an F1/F500 on super EQ steroids!

IMO and limited IME.

 

[Chef]

Two responses to Ken's comments:

I don't find the low end of the MB-F as natively extended as say, the Mesa M6/9.
I also don't find the master volumes to be as "off/scream" as the M6/9; and that's a point I noted and appreciated right off...

 

[KJung]

Two responses to Ken's comments:

I don't find the low end of the MB-F as natively extended as say, the Mesa M6/9.
I also don't find the master volumes to be as "off/scream" as the M6/9; and that's a point I noted and appreciated right off...

+1 in that the master volume pot on the M6/M9 is REALLY touchy, and the low end is stupid extended on those IMO.

My comparison and comments on the low end and the master volume pot response of the Fusion was based on the F1/F500 comparison per the request.

 

[tombowlus]

Just kind of curious here, Chef, and maybe you have answered this in a previous thread, but, have you ever tried the Gk 700RBII ? The tone you are describing with this head sounds like the tone I get with my 700RBII, into a 215 cab with horn.

The 700RB-II and the MB Fusion are in the same tonal ballpark, for sure. The main difference I hear is that the MB Fusion adds in more harmonic content. The 700RB-II probably has a bit more solid/even midrange, too. But that difference is not huge.

 

[tombowlus]

While it might sound good with a fearful 15/6/1, I don't think it has the watts to drive that thing to full performance of that cab.

I did not think that one of these heads would be enough to drive a fEarful, either, but then I did a gig with the MB500 and my 12/6cube/1, and it handled things very nicely. I do recommend the MB500 and MB Fusion for folks looking to drive one or two fEarfuls with a compact head. When the MB800 comes out, it's going to be "da bomb" for fEaful-style cabs!

 

[tombowlus]

Max volume seems about the same, but it is hard to tell, since the GK master kind of goes from 'off to scream', so is louder at the same knob settings.

From looking at our bench measurements of those two heads, I think that some of the reason that the GK is louder at the same knob settings is related to how each amp handles limiting. The GK definitely allows the amp to put out more power when it's closer to rails (though the limiter is quite effective - when engaged - at keeping you under the rail limits), and the MB definitely starts pulling back more often and sooner than the GK.

Both are great heads, though, and good designs, IMHO/IME.

 

[KJung]

I did not think that one of these heads would be enough to drive a fEarful, either, but then I did a gig with the MB500 and my 12/6cube/1, and it handled things very nicely. I do recommend the MB500 and MB Fusion for folks looking to drive one or two fEarfuls with a compact head. When the MB800 comes out, it's going to be "da bomb" for fEaful-style cabs!

+1 Especially for the models without a tweeter. The F500 (with the VPF engaged a touch to 'widen it and sizzle it up' a bit), and the inherent tone of the MB500 seem to work really well with those cabs, and there is enough treble juice to extend the top end nicely to the upper range of those mid drivers.

I would think the MB800 would be absolutely perfect for the 8ohm 15/6 when that head is released.

 

[Chef]

"not as loud at same knob settings" is really a useless comparison, IMO, as different manufacturers use different pots, with different tapers.

As has already been alluded to, the M6/9 is an extreme example of this.

 

[KJung]

From looking at our bench measurements of those two heads, I think that some of the reason that the GK is louder at the same knob settings is related to how each amp handles limiting. The GK definitely allows the amp to put out more power when it's closer to rails (though the limiter is quite effective - when engaged - at keeping you under the rail limits), and the MB definitely starts pulling back more often and sooner than the GK.

Both are great heads, though, and good designs, IMHO/IME.

+1 I like that 'limiter disengage' option on the GK heads.... opens it up a bit more in the highs and lows, especially during brief hot transients (like slap hits, or whatever). You will run into trouble if you are really cranking that head without the limiter (it will shut down), but, that's what the limiter is for, and you can engage it when you are really pushing the amp. Nice design.

However, that master knob is still quite goosed early in its travel, but that has always been kind of a thing with the GK heads... not that big of a deal.

 

[KJung]

"not as loud at same knob settings" is really a useless comparison, IMO, as different manufacturers use different pots, with different tapers.

As has already been alluded to, the M6/9 is an extreme example of this.

+1 However, many posts on TB with the 'this amp totally kicks with the master only at 9 o'clock', so I always try to remind TBers about not falling into that trap when comparing amps.

 

[tombowlus]

A lot less expensive!!!!! The Puma is unique, and while it does have a bit of that super extended low end and super extended treble of the GK MB's, it is much cleaner and more 'pure' sounding.... much less grind and aggressive. The low end of the Puma acually sounds bigger and warmer and more 'tubey' than the Fusion, and the top end is much more 'uber clean hi fi' than the grit of the Fusion up top.

I would think that those looking for that big, wide Puma tone would be reasonably happy with the MB500 more than the Fusion, but the MB500 is still much more 'in your face' than the Puma... the GK heads really are super voiced to me.... kind of a 'whoa' response when you first plug them in... that 'knife slice' top end and huge bottom, and that midrange distortion (i.e., that bit of grit built into the voicing of the amp). Again, kind of an F1/F500 on super EQ steroids!

IMO and limited IME.

I have not spent much time with the Puma 500, but I was able to compare the Puma 1000 to both the MB500 and MB Fusion. The overall frequency response does seem to be fairly similar, but the Puma 1000 is much smoother and laid back. Almost glassy. The GK's seem to have more dynamic range on the attack of a note, and they do seem to cut through better. They definitely sound more aggressive in comparison.

What really surprised me, though, is that the MB's were significantly louder than the Puma 1000, even when the Puma was in bridged mode driving an 8-ohm load. This should have been @ 1,000 watts versus @ 350 watts, but the GKs seemed louder. When using one channel of the Puma 1000 versus the GKs into a 4-ohm load (which should be a fair fight), the GKs were significantly louder and the Puma noticeably ran out of steam (I didn't have hearing protection handy, so I did not try to push the GKs until they ran out of steam).

The Puma 500 comparison may be totally different, though, as those two heads (Puma 500 vs 1000) do seem to have their differences.

 

[KJung]

I have not spent much time with the Puma 500, but I was able to compare the Puma 1000 to both the MB500 and MB Fusion. The overall frequency response does seem to be fairly similar, but the Puma 1000 is much smoother and laid back. Almost glassy. The GK's seem to have more dynamic range on the attack of a note, and they do seem to cut through better. They definitely sound more aggressive in comparison.

What really surprised me, though, is that the MB's were significantly louder than the Puma 1000, even when the Puma was in bridged mode driving an 8-ohm load. This should have been @ 1,000 watts versus @ 350 watts, but the GKs seemed louder. When using one channel of the Puma 1000 versus the GKs into a 4-ohm load (which should be a fair fight), the GKs were significantly louder and the Puma noticeably ran out of steam (I didn't have hearing protection handy, so I did not try to push the GKs until they ran out of steam).

The Puma 500 comparison may be totally different, though, as those two heads (Puma 500 vs 1000) do seem to have their differences.

The Puma500 seems to put out about the same max volume as the MB500 I had over here for a while. However, the master volume tapers are SO different, that it is hard to compare apples to apples. With the same bass, the volume seemed to max out at around 11 o'clock on the MB500 prior to distortion, etc., and at a full 4 o'clock on the Puma500.

The other thing that kind of 'fools the ear' is, as you mention above, the ratio of low end to mids. The Puma500 really pumps a lot of deep bass out (i.e., not so much goosed in volume like the GK, but a really deep extension below 40hz or whatever), while the MB500 has a much more aggressive upper mid profile. That mid response will really hit the ears a lot harder than the wide, smooth, creamy voicing of the Puma, and the Puma also tends to push most drivers beyond their mechanical limits versus other heads when pushed, resulting in some compression at the driver end of the signal chain. My guess is, the 'running out of steam' was on the driver end, not the head. Even the mighty 3015LF will crap out long before the Puma1000 reaches its limits.

That being said, if you really want to crank and punch, I do not really recommend the TecAmp stuff... which is all about purity, nuance, and articulation to me.

 

[Sweet_emotions]

Hey Chef,
I know you got the streamliner too and to your experience, what are the differences between both micro head.

 

[Chef]

I've been asked this a lot, and responded a lot.

I gigged the SL900 once, and flipped it as it was just too soft and mid-scooped for me.
Very tubey, which can be nice enough. Not much treble extension, and mids just didn't cut thru the mix enough for me.

The MB-F is very mid present, grindy, punchy, and much less tubey overall. Plenty of mix cutting mids.

 

[Sweet_emotions]

So the SL series are more vintage oriented and the Fusion more in the modern agressive style. Pretty much wath GK as always did. Can anybody compare this ampmto the old 400rb ii? Aside from the power difference for sure.

 

[KJung]

So the SL series are more vintage oriented and the Fusion more in the modern agressive style. Pretty much wath GK as always did. Can anybody compare this ampmto the old 400rb ii? Aside from the power difference for sure.

Totally different from the 400/800 series... much deeper, much more sizzly, and a 'different' sort of GK grind...not as much 'mid meat' to the grunt to my ear. I still think the 400/800 series was the 'pinnacle' of the GK sound...that unique grind that I've never really heard in another amp, including the other GK's. However, those heads were quite attuated in the deep low end, and that is not an issue with the MB series!

 

[tallboybass]

Wow, big thanks to KJ, TB, & Chef...lots of good info there! I finally did a gig with the MB-Fusion & MBE410. I hate to try to talk about it after those guys...but I'll try.

After playing a wedding last night, I'm a little perplexed. It ended up being quite loud, and on a very resonant stage, so this won't be a typical gig for me with this setup. Using Channel B and setting everything 'flat' ('deep' and 'presence' switches off, contour off, and limiter ON) it was way too scooped sounding. The super lows and sizzly highs were dominant in the overall sound. So I started dialing back the 'bass' and 'treble' controls and brought up the 'low mids' a bit. That was better but it still lacked definition. Switching to Channel A slimmed down the sound a bit, but it made the G string sound pretty thin.

I hesitate to even put this info out since the room sounded so bad and the band was playing so freakin' loud... Next weekend I'll be doing my usual casino gig, so I'll be able to directly compare it to my MB212 which totally rules this gig.

 

[DaveAceofBass]

Wow, big thanks to KJ, TB, & Chef...lots of good info there! I finally did a gig with the MB-Fusion & MBE410. I hate to try to talk about it after those guys...but I'll try.

After playing a wedding last night, I'm a little perplexed. It ended up being quite loud, and on a very resonant stage, so this won't be a typical gig for me with this setup. Using Channel B and setting everything 'flat' ('deep' and 'presence' switches off, contour off, and limiter ON) it was way too scooped sounding. The super lows and sizzly highs were dominant in the overall sound. So I started dialing back the 'bass' and 'treble' controls and brought up the 'low mids' a bit. That was better but it still lacked definition. Switching to Channel A slimmed down the sound a bit, but it made the G string sound pretty thin.

I hesitate to even put this info out since the room sounded so bad and the band was playing so freakin' loud... Next weekend I'll be doing my usual casino gig, so I'll be able to directly compare it to my MB212 which totally rules this gig.

I would not judge the amp based on this, it sounds like you were hearing the room more than the amp. I played my first gig with it at a martini bar/high end restaurant/jazz club, and it sounded incredible and everyone was complimenting my tone, both with electric and upright. However, when I played a pops gig with the Charlotte Symphony (electric bass), the tone was buried and awful. But, we did another concert at a different venue and the tone improved. I used it yet again with my fretless this past weekend at the convention center, in a big room. It sounded good but got a little muddy. So, the room plays a big part in how the amp sounds. In a big reverb-y hall, it's not as punchy, but in a carpeted venue, or a smaller place without high ceilings, the tone stomps. Plus, you can really dial in the tone with all of the EQ controls.

By the way, all of my uses with it were with my AccuGroove Tri112L. I might try it with my Bag End S15X-D next time.

 

[Chef]

I don't he's dissin' the head, but, the MBE410 vs the GK212...

 

[tallboybass]

I would not judge the amp based on this, it sounds like you were hearing the room more than the amp.

Absolutely agree Dave! Here at home it kills!! Can't wait to try it at the casino.

OH....and by the way, the tweeter was off, so the sizzle didn't come from that!