GK 800rb overpowering concerns

[bringitlow]

My main rig is a Gallien-Krueger 800rb into an Ampeg SVT-48HE (200 watts RMS @ 8 ohms, 400 watts peak). It sounds great, but at the rare venues without PA support I have to push it pretty hard.

Though the 800rb and Ampeg cab are both rated for 200 watts @ 8 ohms, sometimes I feel like the GK head might be a bit too much for the cab.

My settings are as follows:
Input: Noon
Treble: 9:00
High mid: 11:00
Low Mid: 1:00
Bass: 1:30

Boost: 2:00
Master: 3:00

Since I run the boost pretty high and dial in some added low end, I sometimes get a distorted sound. And here's the issue: I'm not quite sure if this is just trademark GK growl from the amp, or if the cab is giving warning signs. Since the 800rb has no clip indicator I have a hard time in high-volume situations distinguishing amp clipping from the cab "farting out" or telling me I should turn down.

Adding to my concern is the fact that in the 6 months or so I've played this rig a dustcap and a voice coil both came unglued... I'm not sure if this was due to age or overexcursion. A service center I brought the busted speakers declared the former, but still...

On paper, the head and cabinet match, but I'm aware that the GK might be putting out more than the watts it's rated for, especially if I'm cranking it ( GK understates their power ratings, in my experience) and that the Ampeg might not be able to take whatever excess wattage I'm putting into it. I'm at the point where I'm considering going back to the 410hlf, which I sold off in order to downsize, and which offered tons more power handling and low bass than my current 4X8.

Has anyone had experience with this setup or a similar one, who can give their feedback regarding overpowering in this situation?

Thanks in advance for the help!

[Rockmusician]

I would get rid of the 8 ohm cab and get a 4 ohm, or just add another 8 ohm cab. This way you can run 300 watts at 4 ohms. This should be plenty of power. I used to run an 800RB with a 4 ohm cab and played some large venues. I never had a problem hearing myself or pushing my cab too hard.

[Hopkins]

Cab power ratings don't mean much. You are pushing the cab to hard, try and come down on the lows a bit.

[omnimutant]

I'd go back to the 410 personally. The 800rb say's 300@4 Ohms but it's a Monster 300. The 410HLF can Handle all the power you throw at it, and since it's 4ohms you don't have to push it as hard to get the stage volume your missing.

I totally understand the need to downsize for weight purposes, but if your sacrificing that much to just shed a few pounds loading/unloading I think your doing more harm then good.

[billfitzmaurice]

Originally Posted by bringitlow

Though the 800rb and Ampeg cab are both rated for 200 watts @ 8 ohms, sometimes I feel like the GK head might be a bit too much for the cab.

Wattage ratings are meaningless. If you can't get loud enough with one cab add a second, identical to the first. Leave the second cab at home when you don't need it.

[cchorney]

The GK 800RB has 2 amps, a 300 watt 4 ohm and a 100 watt 8 ohm. Sounds like you are running your 8 ohm cab into the 4 ohm side to get that 200 watts. Not a problem, just reviewing the situation before I go on to my opinion stuff.

I would run the existing 200 watt RMS 8 ohm cab from the 8 ohm side, and get a 400 watt RMS (or more) 4 ohm cab for the 4 ohm side. That would make a solid "handle just about anything" rig. You could then bring just the 4 ohm cab for smaller gigs, and since the amp would be running at 300 watts instead of 200 watts, you wouldn't have to worry as much about pushing the rig too hard.

So to be clear, a single 4 ohm cab rated for 400 watts RMS or more should be louder on your GK 800RB than your existing 8 ohm cab, which means you can run both channels and both cabs and impress the ladies and children, or you could sell the 48HE and just run 1 cab and end up producing more sound anyway.

BTW, I found that the boost was always too hissy on mine, so I left it dialed down and just used the master vol to control my volume.

[will33]

The power difference from 200 to 300 watts is hardly even audible, especially when your cab is struggling with the 200. You're simply pushing the cab too hard. At louder volumes it can be hard to distinguish between growl/distortion effects and cab farting.

Basically follow Bill's advice and get another cab for when you need it.

You can dial back the boost knob to get a clean sound, then add that volume back with the vol. and master and listen to the cab. If you're still getting the growl effect, it's the cab making it. Try dialing the bass down and bumping the lowmid knob to thicken up the sound. If that stuff doesn't help, you simply need another cab, you've reached the limits of this one.

[bringitlow]

Thanks for all the great advice, guys. It's very much appreciated.

I do have a SVT-15e that I leave at my rehearsal space, but for some reason something sounds off ( to my ears, anyway) when I combine the 4X8 and the 1X15 on the 800rb's low section. It seems to get really " honky" and lose some low bass. I guess I'm not really a fan of mixed speakers, or there is some phasing going on. I haven't tried it really in a bi-amp setup though, could this be the key?

Awhile ago I tried to get another 4X8, but those are really hard to come by. At this point it's clear that I have two cabs, neither of which can be used as standalones, and which don't play nice together. Maybe this is my cue to go back to a 4X10 setup...

Another option would be to ditch the 4X8 and get another 115, I suppose.

I do need something compact though, and preferably a single high power handling cab, as when my band travels out of town we are really tight for space in our minivan. That lack of space was a major reason why the 410 hlf got the boot.
I'm not really into too much high-end when it comes to bass, and I loved the natural low end of the HLF... Would the SWR Goliath II be a good option? I did some searching and it's pretty compact/ powerful. I've also looked into some Eden cabs too. Is there anything that can come close to delivering similar low end output as the HLF with a high power rating, in a smaller package? Of course, with a smaller box nothing will match it, but what's the closest I can get?

[WingKL]

A Fearful or a Barefaced or a tweeterless BFM Jack 15?

[will33]

If you were used to gigging a 410hlf and then went to this 4x8, just understand all those big lows you used to have just aren't going to be there. You can try dialing a little back in but you'll likely hit the limit pretty quick. A little bump on that eq goes a long way and this current cab just likely doesn't have that much to give down there.

[B-string]

The 800RB has a very large power reserve, I'm suprised you still have a 4X8 cab with working speakers.

[12bass]

Originally Posted by bringitlow

I do have a SVT-15e that I leave at my rehearsal space, but for some reason something sounds off ( to my ears, anyway) when I combine the 4X8 and the 1X15 on the 800rb's low section. It seems to get really " honky" and lose some low bass. I guess I'm not really a fan of mixed speakers, or there is some phasing going on.

Sounds like one of the two cabinets is wired out of phase. Try flipping the wiring in one of the cabinets and see what that combination sounds like.

[sunbeast]

The beauty of the 800RB is that it has a fairly early low end roll off built in (high-pass filter), as did many early solid-state heads. Usually speakers in bass systems are blown by too much deep bass, and the 800RB eliminates alot of that inherently (one of the reasons it is usually considered such a punchy amp- alot of power in the low mids instead of deep bass). That said, using more speakers is a better idea than pushing your amp and cab very hard and will ultimately reduce undue stress on both.

[maxbass]

maybe your problem is the 8" speakers.
I ofen gig with an old 200 watts 410HE with my RB800; even when the rig is pushed at a loud volume everything seems all right

[jg919]

Hi!
I have been unsing my 800rb ('86) EXTREMELY happily for the last 12 months or so.
I have a geat suggestion for those of us who love a great 800rb rig, but don't like too much weight - get 3 2x10" cabinets (I have english-made Ashdowns) - this way, you can choose exactly how many cabs you require for the gig, and if you're taking all, it sounds great to run 2 8 ohm 2x10"s for the 300w low amp, and the last 2x10" for the high amp!
I sit my 3 2x10"s atop each other, and tilt the top cab (high amp) on a little angle, so it's right in my ear for smaller stages.
Sometimes though, try sitting both low amp 2x10"s on the ground next to each other, and tilt the top 2x10" on a greater angle - very wide dispersion of sound!
My 800rb sits next to the rig in a road-case...but easily sit it on top if you don't want to angle your speakers or don't have a road-case.
I like to bi-amp the rig, just for the exra clarity (best used in conjunction with the high-boost, and then adding in some low-end on the eq).
Anyway, if you're reconfiguring your rig - give it a try!
Thanks, JOHN

[johnk_10]

judging by your settings, you'll getting all of the power that the 800RB has to offer at 8 ohms. the problem is that your cab is not making any where near the most of it.

and i agree with Jon, that i too am surprised that your 4x8 isn't toast by now.

[B String]

Originally Posted by cchorney

The GK 800RB has 2 amps, a 300 watt 4 ohm and a 100 watt 8 ohm. Sounds like you are running your 8 ohm cab into the 4 ohm side to get that 200 watts. Not a problem, just reviewing the situation before I go on to my opinion stuff.

I would run the existing 200 watt RMS 8 ohm cab from the 8 ohm side, and get a 400 watt RMS (or more) 4 ohm cab for the 4 ohm side. That would make a solid "handle just about anything" rig. You could then bring just the 4 ohm cab for smaller gigs, and since the amp would be running at 300 watts instead of 200 watts, you wouldn't have to worry as much about pushing the rig too hard.

So to be clear, a single 4 ohm cab rated for 400 watts RMS or more should be louder on your GK 800RB than your existing 8 ohm cab, which means you can run both channels and both cabs and impress the ladies and children, or you could sell the 48HE and just run 1 cab and end up producing more sound anyway.

BTW, I found that the boost was always too hissy on mine, so I left it dialed down and just used the master vol to control my volume.

What the?!?!
Maybe you didn't read the specs right. The GK800 in the full range speaker outs offer 300 watts into a 4ohm load, or 200watts into 8ohms. The high end outs offer 100 watts with a variable crossover point. The OP is running 200 watts into the Ampeg box he has now.

I've seen this hundreds of times before with students. Its just too much volume for one relatively small cab. And probably hitting it too hard. (right hand) Use more speakers or a much better 210 box with better specs. Love the GK800rb.

[lowendrv]

Originally Posted by 12bass

Sounds like one of the two cabinets is wired out of phase. Try flipping the wiring in one of the cabinets and see what that combination sounds like.

Heres some good info in general...read the 7th paragragh, much easier way to test speaker phasing..

http://www.swramps.com/support/setuptips.php

[gustobassman]

I run an 800Rb as well, and a good tip, is to follow what the manual says. You want the MASTER to be at almost full. i set it back just a hair. Then use the eq (start "flat", let your ears be the judge on what needs to be added), and finally the input volume until it gets distorted or to your liking. Obviously room acoustics and active preamps make a huge difference. I've never been "underpowered" using this method..

Also, like most have said, you are lucky you didn't fry the 4x8. get a 4ohm cab, i use an Ampeg 610HLF, and you can get the full 300 watts which is pretty darn loud.

EDIT: just realized you were looking for something smaller. It's hard to get that bottom end you want without more speakers. a 2x10 will sound good, but it's not the same as a 4x10. more speakers = more bottom/louder, to my ears at least..

[cchorney]

Originally Posted by B String

What the?!?!
Maybe you didn't read the specs right. The GK800 in the full range speaker outs offer 300 watts into a 4ohm load, or 200watts into 8ohms. The high end outs offer 100 watts with a variable crossover point. The OP is running 200 watts into the Ampeg box he has now.

I've seen this hundreds of times before with students. Its just too much volume for one relatively small cab. And probably hitting it too hard. (right hand) Use more speakers or a much better 210 box with better specs. Love the GK800rb.

I'm not seeing your confusion. It looks to me like we're both saying same thing.