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GK RB 700 2 or GK MB500

The bi amping only applies if you are using compatible GK cabs. I had the same dilemma but went with the MB500 as it sounds wonderful, has the switchable boost channel and is amazingly small and light. The 700 is a pretty light amp for what it is but I already have a Mesa Carbine and simply wanted a super portable head that would give me the famous GK tone. I have owned a Shuttle6, LMIII and now the MB500 and I prefer the overall tone and feature set to the other two.
 
I've owned a myriad of GK heads - 1001 RB II as opposed to 700 though. I currently own the MB2-500. Love it... I don't see any advantage to the 700 at this point and unless you really need the power, not the 1001 RB II either.
 
IMO the bi-amping is not pointless and is, in fact, a great feature.

I would say more that "in your opinion" it's a great feature. I've tried it and I find it to be useless -- all it does for me is what you could do by turning down the high mid eq knob or using the contour knob. Hollows out the area between your tweeter and woofers.

In My Opinion it's pretty pointless. Why? Because:

The crossover frequency is too high (5khz) - the cabinets that have it want a crossover frequency closer to 2500hz or less.
 
I would say more that "in your opinion" it's a great feature. I've tried it and I find it to be useless -- all it does for me is what you could do by turning down the high mid eq knob or using the contour knob. Hollows out the area between your tweeter and woofers.

In My Opinion it's pretty pointless. Why? Because:

The crossover frequency is too high (5khz) - the cabinets that have it want a crossover frequency closer to 2500hz or less.

Well, I would disagree with that.

I think its a fact that its a great feaure that allows the player the option of using it or not. If you don't use the bi-amping and you prefer the sound that way I don't know how it affects you.

Its my "opinion" that the bi-amping sounds good.
 
I've tried to like the MB500. I've played it several times now, did some recording with one back over the summer, and even had one here over a long weekend...... but man, it's missing something compared to the 700. The 700 has this "organic" thing happening that just isn't there in the little MB500. Compared to the 700, the MB is missing some heft in it's tone. Spend time with both, and you'll hear what I'm talking about. And it just won't "GK Grind" like the 700rbII..... no matter how loud you turn it up, and no matter how much boost you use.

And the HMS is a nice feature, but again, try it out and see if it's your thing.
 
I'd say it's just a matter of application and preference for form factor. If your gigging around a lot, and feel the need for a rack mountable, heavy duty head, get the RB. If a 4 lb. micro suits you, go with the MB. G-K also has the MB Fusion out now which has three tubes in the pre-amp, and should get you a little more grind and warmth.

Regarding the HMS (bi-amp) feature, I agree with RP on the xover frequency, but with today's two and three-way cabs, I don't see much advantage in bi-amping anyway.
 
I bought and ABed the MB500 and RB700-II. I took back the RB700-II. They had essentially the same preamp. The 700 had a presence control and biamping. Neither of which justified to me an extra 15 lbs. and $100. I put my MB500 in a back pack. After lucking around a 2 space rack mounted head that weighed 30 lbs with rack, I am very happy to have the MB500 form factor and sound.
 
I would say more that "in your opinion" it's a great feature. I've tried it and I find it to be useless -- all it does for me is what you could do by turning down the high mid eq knob or using the contour knob. Hollows out the area between your tweeter and woofers.

In My Opinion it's pretty pointless. Why? Because:

The crossover frequency is too high (5khz) - the cabinets that have it want a crossover frequency closer to 2500hz or less.

I was told that the point of GK HMS/Bi-Amp system is to keep the GK "Growl" out of the tweeter. I've had a 700RB and now have an MB500 and do notice the difference, but I run with my tweeter just barely audible so it's really no big deal. If you like clean bright highs then the 700RB will give you more control over this (with a GK cab of course).
 
I was told that the point of GK HMS/Bi-Amp system is to keep the GK "Growl" out of the tweeter. I've had a 700RB and now have an MB500 and do notice the difference, but I run with my tweeter just barely audible so it's really no big deal. If you like clean bright highs then the 700RB will give you more control over this (with a GK cab of course).

There are about 800 ways to achieve the same thing that don't require a separate amp and an electronic crossover. And also just using a better electronic crossover frequency and better high frequency device that can handle being crossed lower.

The GK Biamp sounds very hollow to me. Everything above the woofers' rolloff before 5khz is gone. Meh. That's a lot of sound :)
 
There is something about the RB 700II that, for lack of a better definition, is intangible. I have'nt played the MB500, but I have played the MBF1 ( which I like ), the GB Shuttle, the LMII, and the Carvin BX500. It sounds different than all those others in a way that I can only describe as " solid " in tone. I don't know if it's the combination of Boost, Presence, etc., or what, but it is definitely there, even when running everything flat, as compared to the other 500 watt lightweight heads. It definitely sounded better with my old school 215 cab than the F1. But, if you are into an easier schlepp, then, the lightweight heads are the way to go.
 
IMO the bi-amping is not pointless and is, in fact, a great feature.

If you have GK cabs (with the bi-amp feature - not all of them have this), then I would agree. I wasn't really ever very excited by that feature until I used it live with a full GK rig. :cool:

That being said, the MB500 is one heck of a nice amp, and one of my favorite of the micro heads on the market. The MB Fusion is another of my favorites.

At any rate, the MB500 and the 700RB-II do sound a lot alike, but with the differences in the controls, as listed above. Our testing would indicate that the 700RB-II has a definite advantage in the dynamic power department, but both heads provide more than giggable volume, IME/IMHO.
 
Just got my MB500 (not the MB2 500) just four days ago, and already can't live without it anymore. I'm playing a RB1001 ever since it came out 12 years ago, and still love it. The MB500 sounds extreamly similar and in my opinion has all the features it needs. Yes, it does miss the presence poti and the bottom knob, but to My mind the MB sounds like an RB with the Bottom knob engaged and I don't miss the presence control. I would strongly advice you to buy the MB500, it sounds fantastic (already used it for a concert, a rehersal and for teaching), and it's weight is a sales point in its own.
 
As I understand the 4 string / 5 string switch on the 700, it is there to emulate the older GK products that had a low bass cut. They did this to save on the high power needed to drive the lowest frequencies back when electronics and speakers were less efficient. This allowed GK to make small products for the day. As technology advanced, they added the 5 string switch to remove the low bass cut yet one could still emulate some of the high bass / low mid emphasis on the older GK amps with the filter engaged (4 string mode). The MB500 does not have this switch as it does not have the low bass cut filtering. The MB500 is like having the 5 string switch engaged.
 
My matching MB500 soft carry bag came in today. I am picking it up tomorrow and will give a report on its quality. If its not a good bag I will look for something else but the photo on the GK site looked cool as the bag has a second compartment to hold cables, footswitch, etc.