NAD: 1992 Gallien-Krueger 400RB

[Minininjarob]

12 minutes ago, ossyrocks said:

Ok, I've not posted in this thread for a while, but today I picked up my first 400RB MK4. It's in good nick, working fine, and sounds very nice. It doesn't sound exactly the same as the earlier MK1 and MK2, but it has it's own thing going on and I do like it. The settings on the amps in the pic are the ones which most make the amps sound like each other. Notice the lower setting on the Boost pot, as the MK4 seems to have lot more boost on tap, and also slightly more Treble and High Mid is required to make it sound like a MK2. The Mk4 also has a more pronounced bottom end, like it's extended in the lower frequency range vs the MK1 and MK2. I do perhaps regret selling my MK3 to @Minininjarob, because if I hadn't I would now have the full set!

Looks great! And you’re never getting your Mk3 one back, sorry, I love it too much!! On the plus side a few people have tried my amp out at gigs and they love it, so at least it’s being used to spread the GK joy around. I use mine with a modern GK CX210 and it sounds glorious. 
I used to wonder why you owned so many but I am constantly on the hunt for another GK, but I’d actually want a 700rb just to have a bit more power available - not been short of it to be honest but I’d like to try one and it’s always good to have spares!! 
 

[Minininjarob]

On 14/03/2025 at 17:33, The fasting showman said:

I just got another 700rb power amp module for £30 and a preamp for £15.

Repairers can't seem to be bothered with fixing them so it's a good backup. 

 

I've used my old 700rb for 10 years so they work for me, small enough and more than loud enough so if I can keep it working myself, all good. 

 

Thanks for the heads up

I think I could fix one if I got the chance, I do have a background in electronics and I’d love to have a go and bringing one back from the dead so let me know if you ever find one. 

[ossyrocks]

This latest 400RB came with a cab too, a 4ohm 212MBE. It's well used, but working well via the speakon.

 

It's missing part of the 1/4" input jack socket, ie the bit that screws in from the outside of the panel. It has clearly become loose and then lost. I've been through my spares and don't have anything.

 

Long shot - Does anyone have a spare, or can point me to the right part? The socket inside is PCB mounted to the board and appears to be fine.

EDIT: Just found something on ebay which was worth a punt for £3.95. We'll see!

 

Rob

 

Edited 7 hours ago by ossyrocks

[Minininjarob]

47 minutes ago, ossyrocks said:

This latest 400RB came with a cab too, a 4ohm 212MBE. It's well used, but working well via the speakon.

 

It's missing part of the 1/4" input jack socket, ie the bit that screws in from the outside of the panel. It has clearly become loose and then lost. I've been through my spares and don't have anything.

 

Long shot - Does anyone have a spare, or can point me to the right part? The socket inside is PCB mounted to the board and appears to be fine.

EDIT: Just found something on ebay which was worth a punt for £3.95. We'll see!

 

Rob

 

That looks really good and should sound thunderous with the amp. 
If the board inside has flexed when the jack socket was loose the tracks might have become cracked so check it over when you next disassemble it to make sure it’s all ok. 
 

I used a jack to speakon cable for my 400 to my modern gk cab, had it made for me in the correct length. Wish my 400 had a speakon output as it’s more secure but it seems to be working well as is anyway. 
 

Edited 7 hours ago by Minininjarob

[ossyrocks]

5 minutes ago, Minininjarob said:

That looks really good and should sound thunderous with the amp. 
If the board inside has flexed when the jack socket was loose the tracks might have become cracked so check it over when you next disassemble it to make sure it’s all ok. 
 

I used a jack to speakon cable for my 400 to my modern gk cab, had it made for me in the correct length. Wish my 400 had a speakon output as it’s more secure but it seems to be working well as is anyway. 
 

The cab is working fine, and the guy I got it off used a jack to speakon, so he didn't use that jack socket on the cab. But I'll check it over anyway.

I won't be keeping the cab I don't think, whilst I can secrete RB heads here and there without arousing much suspicion, cabs are harder to hide, and with the addition of this one, there are now three cabs in the conservatory. The cab came with the head, so I didn't have a choice whether or not to take it.

[Minininjarob]

2 minutes ago, ossyrocks said:

The cab is working fine, and the guy I got it off used a jack to speakon, so he didn't use that jack socket on the cab. But I'll check it over anyway.

I won't be keeping the cab I don't think, whilst I can secrete RB heads here and there without arousing much suspicion, cabs are harder to hide, and with the addition of this one, there are now three cabs in the conservatory. The cab came with the head, so I didn't have a choice whether or not to take it.

I would be interested in the cab if you didn’t want it. Depends on price of course! 

[ossyrocks]

3 minutes ago, Minininjarob said:

I would be interested in the cab if you didn’t want it. Depends on price of course! 

Ok, you can have first dibs. I'll sort it out first and make sure it's tip top.

It is surprisingly light for a 2x12. I think they use the same drivers as the NEO range. It's a one hand lift....carefully.

Edited 7 hours ago by ossyrocks

[The fasting showman]

Rob, on ebay Polar Audio are selling a new preamp board for a mk4 with pots and jacks for £15. I'd snap it up mate

[The fasting showman]

Gallien Krueger Preamp Board A for 400RB IV Bass Amp Head - OEM Part | eBay UK https://share.google/kMeJNe4mPvyLJMJ64 

 

Edited 3 hours ago by The fasting showman
Error

[ossyrocks]

34 minutes ago, The fasting showman said:

Gallien Krueger Preamp Board A for 400RB IV Bass Amp Head - OEM Part | eBay UK https://share.google/kMeJNe4mPvyLJMJ64 

 

Done!

 

Thanks for the heads up Martin!

[The fasting showman]

5 minutes ago, ossyrocks said:

Done!

 

Thanks for the heads up Martin!

Good man; pots and jacks are the Achilles heel