GK MB 200: Part Two

[craig.p]

Yep, there it is. The fact it's 8 ohms doesn't help. Also check out the various threads here on isobaric cabs. That 410 specifically seems to need a lot of "juice" to get going.

[kevdabass]

Cheers Craig. Yep - makes sense...you've got 1200w handling with the 410, and a distorted signal going in, its not going to be pulling up any trees I suppose!

[drpepper]

Originally Posted by kevdabass

Of course I would normally agree a maxed out solitary volume control would overdrive the sound, but it starts out sounding fine, and gets worse. I have an Orange 4x10 isobaric cab, and unfortunately its 8 ohms - so could do with adding another cab to get down to 4 which will at least give me more headroom.

My first mistake was thinking I could get away with the MB200...I need the big brother! :-)

Admittedly, I'm just about 100% speaking out of the side of my neck here...I have no experience with isobaric speakers. Actually, I didn't even know about the Orange isobaric cabinets, so I did a search. On the wikipedia page, there's an item about distortion

"[distortion may] occur when the speaker [is] driven to high levels for an extended period of time and the voice coils of the two drivers dissipate at different levels because of differing air circulation (one driver is exposed to the outside air, and one is fully enclosed in a chamber)."

I wonder in your case if the pushing to "high levels," not high for the cabinet itself but on the amp's end, could cause the same effect.

A possible thought.

[kevdabass]

Originally Posted by drpepper

Admittedly, I'm just about 100% speaking out of the side of my neck here...I have no experience with isobaric speakers. Actually, I didn't even know about the Orange isobaric cabinets, so I did a search. On the wikipedia page, there's an item about distortion

"[distortion may] occur when the speaker [is] driven to high levels for an extended period of time and the voice coils of the two drivers dissipate at different levels because of differing air circulation (one driver is exposed to the outside air, and one is fully enclosed in a chamber)."

I wonder in your case if the pushing to "high levels," not high for the cabinet itself but on the amp's end, could cause the same effect.

A possible thought.

DoctorP: Not having passed physics at school, I'm not sure of the difference myself! Is one driving the cab too hard by shoving a distorted signal into it? Probably not I'd think.....in fact as Craig says, the iso cab needs driving quite hard to get the most out of it. I'm using the set up again tomorrow night, so I'm going to try a couple of the suggestions on here!

[johnpbass]

Just curious - has anyone tried running the line out on the MB200 to an external power amp? I'm wondering if that would be a good way to scale up for a larger gig. I love the tone of this little amp!

[kevdabass]

Originally Posted by johnpbass

Just curious - has anyone tried running the line out on the MB200 to an external power amp? I'm wondering if that would be a good way to scale up for a larger gig. I love the tone of this little amp!

Used it with a Crown XLS1000 last year - sounded superb

[johnpbass]

Good to know kevdabass. That adds a lot of versatility to this great piece of gear.

[Vic]

Originally Posted by kevdabass

Used it with a Crown XLS1000 last year - sounded superb

Which output did you use on the MB200, 1/4" line out?

[kevdabass]

can't be sure to be honest - stage crew was organising the backline - but I assume so.

[johnpbass]

I would think so too. The 1/4" jack switchable between line out/ headphones.

[Vic]

Originally Posted by johnpbass

I would think so too. The 1/4" jack switchable between line out/ headphones.

Yeah, if you care about having a DI feed, the 1/4" is your man (otherwise, if you don't, the DI out is also an option), but my next question, which I can't find the answer to in the MB200 manual, and I've never tested mine for (yet) is if the 1/4" is post or pre. I assume post, otherwise I'd think the player would be frustrated that they couldn't use the amp's EQ with headphones or as a preamp like this.

Otherwise, if the pre/post applied to both the DI and 1/4", that could be useful, but in some cases a problem, too.

Just curious. I'll figure it out, but I assume the pre/post switch only affects the XLR/DI and the 1/4" is strictly post.

[kevdabass]

1/4" is definitely post EQ.

[Britbonic]

Originally Posted by Vic

Yeah, if you care about having a DI feed, the 1/4" is your man (otherwise, if you don't, the DI out is also an option), but my next question, which I can't find the answer to in the MB200 manual, and I've never tested mine for (yet) is if the 1/4" is post or pre. I assume post, otherwise I'd think the player would be frustrated that they couldn't use the amp's EQ with headphones or as a preamp like this.

Otherwise, if the pre/post applied to both the DI and 1/4", that could be useful, but in some cases a problem, too.

Just curious. I'll figure it out, but I assume the pre/post switch only affects the XLR/DI and the 1/4" is strictly post.

Here's a link to the manual. Block diagram on last page:

http://www.gallien-krueger.com/produ...30-A_MB200.pdf


The 1/4 jack is switchable between headphones and line out and is post eq. The balanced XLR Direct Out is between the preamp and the amp stage and switchable between pre or post EQ.

In general, you'd want to use 1/4 line out for connecting to a power amp and XLR direct out for connecting to a mixer or FOH.

[Vic]

Originally Posted by Britbonic

Here's a link to the manual. Block diagram on last page:

http://www.gallien-krueger.com/produ...30-A_MB200.pdf


The 1/4 jack is switchable between headphones and line out and is post eq. The balanced XLR Direct Out is between the preamp and the amp stage and switchable between pre or post EQ.

In general, you'd want to use 1/4 line out for connecting to a power amp and XLR direct out for connecting to a mixer or FOH.

I'm gonna' step up and admit how stupid I was right now.

I actually did look at that manual, in hopes that it had a block diagram, but for some reason, I stopped reading at the text definitions of the connections. Don't ask me why my brain stopped working. Sometimes it just does.

[johnpbass]

I do the same thing with manuals - I skim the text and if something looks close I'll just stop at that point.

All good info here though. I'm going to try the 1/4" out. I don't have a "real" power amp but I'll try the good old patch into the effects return method of one of my other amps.

[kevdabass]

I usually use manuals to prop up rickety tables......

[Vic]

Originally Posted by johnpbass

All good info here though. I'm going to try the 1/4" out. I don't have a "real" power amp but I'll try the good old patch into the effects return method of one of my other amps.

I also think you could just run the line out into the regular input of another amp if you did want to use its effects loop. Even if it was a tad hot (though I don't think it would be), most amps have pads these days if needed.

[johnpbass]

Originally Posted by Vic

I also think you could just run the line out into the regular input of another amp if you did want to use its effects loop. Even if it was a tad hot (though I don't think it would be), most amps have pads these days if needed.

Good point Vic - I'll try both methods.

[johnpbass]

Okay, so I tried this last night. I don't have a power amp so I ran the Line Out from the MB200 into the effects return of my Genz Shuttle 6.0 into 2 GB Focus 115s. The result surprised me a bit - the tone lost a lot of the presence and edge.

Seems like the power amps in the GK and Genz factor into the tonal equation quite a bit? I would have thought the amps themselves were fairly neutral sounding but according to my quick test, there were definite voicing differences coming into play.

I guess the better test would have been to run to a "real" power amp, which typically do not color the tone.

[Vic]

Originally Posted by johnpbass

Okay, so I tried this last night...

This is very interesting... looking forward to more results...