GK Neo 4 ohm: get another? Heads?

[123four]

Using a GK 400rb. I got the 4 ohm Neo 2x12 so I could get maximum wattage out of the head, but now I’m thinking I need another 2x12. If I get another 4 ohm, I can’t run 2 ohms with the 400rb.

So I could either try and change the drivers on the current one to 8 ohm and get another 2x12 8 ohm for a 4 ohm load or get another 4 ohm 2x12 and find another head to use with the two, and keep the 400rb as a backup when I only need one 2x12.

Thoughts, suggestions? What head would you recommend that can do 2 ohms? Looking to spend maybe $600-700 used.

I play loud/heavy music so something that can keep up with a loud drummer.

 

[Lammchop93]

If you insist on doing 2 ohms, I think the GK legacy 1200 is probably your best bet. It can sound like what you have, and go to 2 ohms.

Or honestly, I would get a RB700RB-II or RB1001RB-II used for under $500 and run that into your existing 4 ohm 212. That should be plenty loud

 

[Wasnex]

My guess is many people suggested getting an 8 ohm cab. Now you know why .

Assuming the required OEM replacement drivers are available they won't be cheap.

16 Ohm Neo 2 x 165 = $330 + shipping and tax.

IMHO sell the 4 ohm cab and get two 8 ohm cabs.

 

[agedhorse]

My guess is many people suggested getting an 8 ohm cab. Now you know why .

Assuming the required OEM replacement drivers are available they won't be cheap.

16 Ohm Neo 2 x 165 = $330 + shipping and tax.

IMHO sell the 4 ohm cab and get two 8 ohm cabs.

That's not true...

The single 4 ohm 212 has way more power handling that the little 400RB can produce, so adding another cabinet (regardless of impedance) makes little no sense. The amp is grossly under-powered IMO.

The 400RB is rated between 200 watts and 280 watts into 4 ohms (depending on the version), if the OP needs more volume, a larger amp is much more suitable to the speaker he has than more speakers are to the amp.

One of the larger, newer GK amps would be a much better choice, and get to the goals with the least amount of cost and hassle. The Legacy 800 might be one to look at, and IF the OP wants another cabinet, that's still an option with the newer amps.

 

[Wasnex]

That's not true...

The single 4 ohm 212 has way more power handling that the little 400RB can produce, so adding another cabinet (regardless of impedance) makes little no sense. The amp is grossly under-powered IMO.

The 400RB is rated between 200 watts and 280 watts into 4 ohms (depending on the version), if the OP needs more volume, a larger amp is much more suitable to the speaker he has than more speakers are to the amp.

One of the larger, newer GK amps would be a much better choice, and get to the goals with the least amount of cost and hassle. The Legacy 800 might be one to look at, and IF the OP wants another cabinet, that's still an option with the newer amps.

I don't contest that the amp is relatively low powered or say he shouldn't buy a more powerful amp.

Neo 212 is rated 101dB 1W/1m.

400RB mk IV is rated 180W at 8 ohms and 280W at 4 ohms

Calculated SPL:

• One 8 ohm cab at 180W = 123.5dB
• One 4 ohm cab at 280W = 125.5dB
• Two 8 ohm cabs at 280W = 128.5dB
• One previous Gen NEO 212 full rated power (600W) = 128.8dB
• One Mk IV NEO 212 a full rated (800W) = 130dB

Comparisons:

• In this case choosing one 4 ohm cab over one 8 ohm cab gets you 2dB. Barely noticeable.
• Choosing two 8 ohm cabs over one 4 ohm cabs get you 5dB. Much more noticeable.
• Depending upon which series of NEO 212 he has, getting a more powerful amp could potentially net +5.3dB at 600W or +6.5dB at 800W.
  • With a single previous Gen Neo 212 at 600W you get +0.3dB over two 8 ohms cabs at 280W
  • With a single Mk IV Neo 212 at 800W you get +1.5dB over two 8 ohms cabs at 280W

For me a pair of 212s at 280W would probably exceed the vast majority of my requirements. Also, I personally think it's better to have a couple of cabs coasting along well below their rated power limit, rather than hammering a single cab for everything it's worth; especially since power handling specs are sometimes a bit optimistic.

Now the OP can choose from range of options, depending upon how loud he needs to play, how much he wants to spend, and what his philosophy is on modular rigs.

 

[agedhorse]

Which version of the 400rb does the OP have?

Where the 800 really shines is that when you use 1 x 4 ohm cabinet he will get about 5dB more but if he uses 2 cabinets he will get ~8dB more.

There's "coasting" and there's leaving a LOT of performance on the table.

 

[S-Bigbottom]

GK Legacy, MB Fusion or anything in the Mesa Subway line.

 

[KevInDaBassment]

...I got the 4 ohm Neo 2x12 so I could get maximum wattage out of the head, but now I’m thinking I need another 2x12...

Thoughts, suggestions?...Looking to spend maybe $600-700 used....

Going 4-ohm with a single cab to "get the most" out of your amp is a common mistake, but still a mistake nonetheless... (in this particular case anyhow)

1) You could sell or return the Neo 2x12 and get the 8 ohm version
2) Sell your GK head and buy an amp that does 2 ohm loads
3) Buy a power amp that goes down to 2 ohm (or 4 ohm stereo, which should functionally work the same). You can run the preamp out from your GK head into the power amp.

Now, if you have a budget of $600-700 you may or may not be able to do option #2. However, with that budget you could easily do option #3. You'll get something that can properly utilize the cabinet to its fullest, plus you can always drive the power amp with a preamp pedal or rack preamp if you like. Ultimately it's your money and your journey...this is all just my $0.02

My additional $0.02 is that when cab manufacturers make cabs smaller than a 4x10 or 2x15 in 4 ohm, it just makes me want to facepalm. I realize I'm no Bob Gallien (love your amps btw, Bob), it just seems like the benefits of doing a 4-ohm in cabs with those configs isn't all that compelling...but that's just my opinion

 

[Clark W]

Using a GK 400rb. I got the 4 ohm Neo 2x12 so I could get maximum wattage out of the head, but now I’m thinking I need another 2x12. If I get another 4 ohm, I can’t run 2 ohms with the 400rb.

So I could either try and change the drivers on the current one to 8 ohm and get another 2x12 8 ohm for a 4 ohm load or get another 4 ohm 2x12 and find another head to use with the two, and keep the 400rb as a backup when I only need one 2x12.

Thoughts, suggestions? What head would you recommend that can do 2 ohms? Looking to spend maybe $600-700 used.

I play loud/heavy music so something that can keep up with a loud drummer.

Mesa D-800+, 400 watts @ 8 ohms, 800 watts @ 4 & 2 ohm. I run my Mesa with a 4 ohm GK Neo IV 212, have considered getting a 2nd 4 ohm GK Neo IV 212. I'm sure it would be monstrous. I have ran 4, 8 ohm cabs off the Mesa head before, two Markbass 115 and two Markbass 210 cabs and it was huge sounding, I suspect two GK Neo IV 212 cabs would be too.

 

[agedhorse]

Going 4-ohm with a single cab to "get the most" out of your amp is a common mistake, but still a mistake nonetheless... (in this particular case anyhow)

1) You could sell or return the Neo 2x12 and get the 8 ohm version
2) Sell your GK head and buy an amp that does 2 ohm loads
3) Buy a power amp that goes down to 2 ohm (or 4 ohm stereo, which should functionally work the same). You can run the preamp out from your GK head into the power amp.

Now, if you have a budget of $600-700 you may or may not be able to do option #2. However, with that budget you could easily do option #3. You'll get something that can properly utilize the cabinet to its fullest, plus you can always drive the power amp with a preamp pedal or rack preamp if you like. Ultimately it's your money and your journey...this is all just my $0.02

My additional $0.02 is that when cab manufacturers make cabs smaller than a 4x10 or 2x15 in 4 ohm, it just makes me want to facepalm. I realize I'm no Bob Gallien (love your amps btw, Bob), it just seems like the benefits of doing a 4-ohm in cabs with those configs isn't all that compelling...but that's just my opinion

This is a 212, and is being grossly under-powered for the volume that the OP is looking for. It's leaving a lot of potential performance on the table.

The problem (root cause) is a poor choice of amp for the needed volume. Either a larger amp (suitable for the 4 ohm 212) cabinet, or two x 8 ohm 212's (a more expensive and cumbersome approach) might work, but 200-250 watts into 2 x 212's is more expensive and larger (size/weight) overall.

I have always designed 212's to be 4 ohms, but they handle 600-800 watts RMS (mechanically/thermally) and are a good match for much larger amps that the OP has. IMO, an 8 ohm 212 handling 600-800 watts is pretty useless for most players, since most larger amps deliver ~400 watts into 8 ohms.

 

[KevInDaBassment]

This is a 212, and is being grossly under-powered for the volume that the OP is looking for. It's leaving a lot of potential performance on the table.

The problem (root cause) is a poor choice of amp for the needed volume. Either a larger amp (suitable for the 4 ohm 212) cabinet, or two x 8 ohm 212's (a more expensive and cumbersome approach) might work, but 200-250 watts into 2 x 212's is more expensive and larger (size/weight) overall.

I have always designed 212's to be 4 ohms, but they handle 600-800 watts RMS (mechanically/thermally) and are a good match for much larger amps that the OP has. IMO, an 8 ohm 212 handling 600-800 watts is pretty useless for most players, since most larger amps deliver ~400 watts into 8 ohms.

For the record, I love your amps too @agedhorse...just can't afford yours or Bob's new stuff (yet...) at this point in my "I can't afford a home" part of my career

Yeah a beefy 2x12 that's 4 ohm makes sense with those numbers, if only the other MFGs would be that honest with their wattage ratings too

 

[DWBass]

Any 500w (@4ohms) amp along with that cab will be pretty loud. Question is.....how loud do you need to be???

 

[123four]

Cab is the Neo IV.

I had an 800rb but preferred the tone of the 400rb.

I got the cab based on getting max power from the head which is retrospect I see may not have been the wisest decision as I pigeon holed myself around the head but I can get a more powerful head.

Seems that is the better route then selling the Neo - at a loss since I got it new - or redoing the drivers.

When using the preamp out on the 400rb, do I need to have the 400rb in a dummy load? If I decided to go the power amp route.

 

[SactoBass]

Using a GK 400rb. I got the 4 ohm Neo 2x12 so I could get maximum wattage out of the head, but now I’m thinking I need another 2x12. If I get another 4 ohm, I can’t run 2 ohms with the 400rb.

So I could either try and change the drivers on the current one to 8 ohm and get another 2x12 8 ohm for a 4 ohm load or get another 4 ohm 2x12 and find another head to use with the two, and keep the 400rb as a backup when I only need one 2x12.

Thoughts, suggestions? What head would you recommend that can do 2 ohms? Looking to spend maybe $600-700 used.

I play loud/heavy music so something that can keep up with a loud drummer.

Would an option be for you to keep the rig you have, and get a second matching 4 ohm Neo 2x12 cab and a second GK 400rb amp to drive that second cab? That would give you two separate rigs that you could run at the same time, and if one of the rigs ever failed during a gig, you could still finish the gig with the working rig. I do not know if this option would be within your budget. I'm just throwing the idea out there for consideration.

 

[agedhorse]

Cab is the Neo IV.

I had an 800rb but preferred the tone of the 400rb.

I got the cab based on getting max power from the head which is retrospect I see may not have been the wisest decision as I pigeon holed myself around the head but I can get a more powerful head.

Seems that is the better route then selling the Neo - at a loss since I got it new - or redoing the drivers.

When using the preamp out on the 400rb, do I need to have the 400rb in a dummy load? If I decided to go the power amp route.

Really the wrong head for the task, you would gain 3dB if you had 2 x 8 ohm cabinets which I don't think would be enough and a lot more to carry too.

A larger head will get you ~6dB which is significant without having to carry a second cabinet.

You do not need a dummy load for the 400RB, use the effects send output which is line level, though it's pre-boost circuit it's post everything else.

 

[birminghambass]

I use a 700rb2 into the 8ohm version of your cab. It's capable of volume that nobody should need. I play heavy rock with 2 guitarists. Your cab is fine. Get a more powerful amp. The 800rb would be massive with that cab.

 

[ctmullins]

“Getting all the Watts” is a common fallacy.

What you really want is decibels. And decibels come from speakers in cabinets.

Sell your 4Ohm cab and get two 8Ohm cabs.

 

[agedhorse]

“Getting all the Watts” is a common fallacy.

What you really want is decibels. And decibels come from speakers in cabinets.

Sell your 4Ohm cab and get two 8Ohm cabs.

No, dB comes from power x sensitivity. Both are equally important.

 

[jthisdell]

More watts is the best solution in this case

 

[ctmullins]

No, dB comes from power x sensitivity. Both are equally important.

Right. I should have explicitly stated so.

My point is that increasing wattage without also increasing speaker displacement is likely to end in disappointment.