MB150E-III Combo as backup for 1001RB-II ?

[DavyR]

Is it safe to use the GK MB150E-III combo as a backup for a GK 1001RB-II into an older rectangular GK NEO 212, this with the internal speaker of the MB150E-III turned off?
AND, if so, since the speakon on the 1001RB-II won't accept a 1/4" cable, how do I remove the plug from the NEO cab's 1/4" input? I turned the nut and it easily loosened but the screw filling the hole will not budge with finger strength.

The manual says:
Full Range ¼’’ Input Jack: Using a standard ¼’’
unshielded speaker cable, this input jack provides full
range operation with any bass amplifier head. Horn Bi-
Amp mode will not work with this jack. Neo cabinets
ship with a removable plug in the 1/4” jack. DO NOT
use tools to remove this plug. It can easily be removed
with your fingers.

The NEO 212 is 8 ohms (2 x 16 ohms in parallel).
The MB150E-III will accept up to 4 ohms with internal speaker turned off.
Therefore, the load on the MB150E-III, with the internal speaker off, will be the 8 ohms of the NEO 212.
Thx.

 

[Redbrangus]

I don't see any reason why that wouldn't work. Obviously it's quite a bit less power, but the amp portion of the combo should be able to drive the Neo 212 cab to some comfortable volume.

 

[InkCow]

Why would you be turning off the internal speaker?

 

[bass player 53]

InkCow is correct.

For the MB 150E III (I have one), GK
used to sell a matching 8 ohm extension cabinet (see photo). You
can use the internal speaker and the
extension cabinet together, or
either one separately.
This is no different than using your
Neo cab with or without the internal
speaker, or each separately.

You can buy an adapter cable as
well. See photo.

You want to confirm if you use
the internal speaker with the
Neo cabinet that they are in phase.
This is easily done with the
9 volt battery test. (Google that).

 

[DavyR]

Why would you be turning off the internal speaker?

I only need the 2 12" of the NEO cab, to keep things simple & even, and so as not to tax the MB150E-III more than necessary...

 

[DavyR]

InkCow is correct.

For the MB 150E III (I have one), GK
used to sell a matching 8 ohm extension cabinet (see photo). You
can use the internal speaker and the
extension cabinet together, or
either one separately.
This is no different than using your
Neo cab with or without the internal
speaker, or each separately.

You can buy an adapter cable as
well. See photo.

You want to confirm if you use
the internal speaker with the
Neo cabinet that they are in phase.
This is easily done with the
9 volt battery test. (Google that).

I have the 150MBX ext cab but do not want to lug it along in addition to the MB150E, as a backup rig.
OK, so, either use a Speakon to 1/4" OR remove the plug on the NEO 212. Thx.

Anyone know how to remove the plug? Thx.

 

[InkCow]

I only need the 2 12" of the NEO cab, to keep things simple & even, and so as not to tax the MB150E-III more than necessary...

You would be pushing less power to it than running without the external cab: 100w vs 150w/3.

The extra 50 watts of power is negligible, but coupled with the third speaker (at ear level) would give a helpful increase to your spl.

 

[Wasnex]

Is it safe to use the GK MB150E-III combo as a backup for a GK 1001RB-II into an older rectangular GK NEO 212, this with the internal speaker of the MB150E-III turned off?

IME the MB150 head will sound great, but it is huge step back in headroom (150W at 4 ohms, 100W at 8 ohms)

If the 212 is 4 ohms, you need to be absolutely certain the internal speaker on the MB150 is disabled. This is very easy to screw up. So it's probably best to not use the MB150 with a 4 ohm extension cab unless it's an absolute emergency. Doing so it an accident waiting to happen IMHO.

If the 212 is 8 ohms, you can run both cabs. However, I believe the sensitivity is fairly low for the MB150's internal speaker. You may find that you have more headroom if you turn off the internal speaker and just run the extension cab. Try it both ways and judge for yourself.

if so, since the speakon on the 1001RB-II won't accept a 1/4" cable, how do I remove the plug from the NEO cab's 1/4" input? I turned the nut and it easily loosened but the screw filling the hole will not budge with finger strength.

I don't understand why you are asking this. Not even sure what you are asking to be honest. Normally a 1/4" plug should simply pull out. The jack in the NEO cab is not supposed to lock onto the plug. If you have a plug stuck into the 1/4" jack, the old jack must be removed and replaced. AFAIK the jack is soldered to a circuit card.

Just took a look at the manual and maybe this is what you mean:

Neo cabinets ship with a removable plug in the 1/4” jack. DO NOT use tools to remove this plug. It can easily be removed with your fingers.​

Use the speakON whenever you run the 1001RB. Use 1/4" with the MB150E.

The 1001RB has speakON for biamping and it also has 1/4" speaker outs that only connect to the woofer amp. Turn off the woofer LPF and the signal is full range. Otherwise it's crossed over at 5kHz.

AFAIK, the original NEO series had this input jack

1. is speakON for biamp. You can also use it for full range.

3. is 1/4" full range only.

2. is the switch to select biamp or full range. If you use input 3 and have the switch set to biamp, the woofers run full-range and the tweeter is disconnected.

 

[DavyR]

Yikes! Things are getting confused, here, but thanks for the replies, etc.
As stated in the OP the NEO 212 is 8 ohms.
I'll try to call GK to see if they can tell me HOW to remove the plug that's in the 1/4" jack input on the back of the NEO 212 cab. (See #3 in the diagram above.)
I'll let yinz know what I find out, etc.

 

[Wasnex]

Yikes! Things are getting confused, here, but thanks for the replies, etc.
As stated in the OP the NEO 212 is 8 ohms.
I'll try to call GK to see if they can tell me HOW to remove the plug that's in the 1/4" jack input on the back of the NEO 212 cab. (See #3 in the diagram above.)
I'll let yinz know what I find out, etc.

The dust cap may be threaded. Try rotating it out like a screw.

 

[DavyR]

The dust cap may be threaded. Try rotating it out like a screw.

The jack plug/dust cap is made of 2 plastic pieces. A screw part without a head that's in the jack and a nut that's over the screw. The nut can be remove from the screw part. I loosened the nut somewhat to use it as leverage to try to pull on the screw part with fingers but the screw won't budge. Since the manual says to pull on the plug to easily remove it with fingers, I would have to assume it's not threaded into the jack. I did try to rotate it out like a screw with finger strength but it won't budge. I left an email with GK. This plug has never been removed since I bought the NEO 212 cab 15+ years ago. Last resort will be pliers/grippers of some sort though the plug/cap is plastic. Thx.

 

[DavyR]

OH, NO! DO NOT PULL ON THE SCREW/NUT! IT'S NOT THE PLUG!
I 'screwed' this up. The PLUG is a very small have small pea size plug/cap at the END of the threaded screw thingie that you pull on to remove with your fingernails. You don't pull on the threaded screw thingie! The threaded screw thingie is the sleeve of the jack that helps support the 1/4" speaker cord end. Needless to say, I broke the screw into pieces trying to remove it. Luckily, the 1/4" speaker cord still inserts into the jack and works. But, it's not as tightly supported, now. I gots to admit that GK failed on this by not explaining in the manual clearly and having a little 2 cent diagram AND the threaded jack is really thin plastic, hardly road worthy.

I received this replay from GK a few hours too late:

You don't turn the nut. The plug is not threaded, it's pushed in and can can remove with your fingernail at the face of the jack. If you look closely you will see where the plug stops near the outer diameter on the threaded portion of the jack at the face.
Thanks,
Jason Finley
GK