Help connecting Laney AOR to stereo cab...

[Nay Gray]

Hey!

I have a couple of questions that I would really appreciate some help with... so here goes.

I recently picked up an old Laney AOR Pro-Tube Lead 50 head in a gear swap. It is a stereo head (it has 2 speaker outputs) that is switchable between 4, 8 and 16 ohms. I bought a Tube Works 4x12 stereo cabinet to play it through, but since the cabinet has no ratings marked on it and this is my first time using a head and cabinet that weren't made to be used together I am very hesitant to just plug it in and play.

The speakers are Tube Works 12g speakers that say 8 ohms, but the bottom of the back is closed so I can't see if they are wired in series or parallel. All I can see when I take off the top back cover is the top 2 speakers which are NOT wired together and wires that run from each of them into the closed portion of the cabinet. Presumably they go to the speakers below them and to the mono/stereo inputs respectively to form left and right pairs.

So my question is this:

How should I connect the head to the cabinet for both mono and stereo settings? Which impedance should I select on the head? My best guess is that they are 16 ohms mono and 8 ohms for each stereo output, but I don't really know for sure.

I would really appreciate any help you can give!

Thanks,
Nat

 

[glassman]

Re: Help connecting Laney AOR to stereo cab...

First, you need to figure out what the impedence of each side of the cab is. If it is wire parallel: it will be 4 ohms per side; if it is wired in series it will be 16 ohms per side. If you have a meter capable of reading ohms, it should be able to tell you which.

The output jacks on the AOR are in parallel; if your cab is 16 ohms per side, the total load the amp will see is 8 ohms. You will need to select the 8 ohm setting on the impedence switch. If your speakers are 4 ohms per side, for a total load of 2 ohms; don't use it. The mono setting for the cab may be 8 ohms; if this is the case, select 8 ohms on the amp. There is no advantage to running the cab in stereo in this setup since the output of the amp is mono.

 

[Nay Gray]

Re: Help connecting Laney AOR to stereo cab...

Thanks for the advice. I checked it out with a meter and it read about 6 ohms per side. I'm guessing that means I should use the 8 ohm switch for mono. Anyway I tried playing it that way and it sounds good!

Thanks

 

[devastone]

Re: Help connecting Laney AOR to stereo cab...

2 speaker outputs DOES NOT = stereo.

It's a mono amp (like 99% of guitar amps) that can run 2 cabinets, the jacks are in parallel on the head. What does the cabinet say on the jacks? It should have a mono jack that you can run one cable to and set the head to match.

 

[scuba]

Re: Help connecting Laney AOR to stereo cab...

Nay Gray,
Contrary to Devastone's info I thought you should know! His post states that 2 speaker outs does not equal stereo. However, in this particular case it does!! I own a Tubeworks 4x12 cabinet and know otherwise. I encountered the same questions after purchasing my Tubeworks 4x12 cabinet. When looking at the cabinet from the back view, the Left side input is a MONO 8 ohms rated input and will drive all 4 speakers, even thought you're getting a 6 ohms rating from the plug - mine does the same. If you plug into the right jack you'll find it around a 3 or 3.5 ohms rating - but plugging into this jack actually separates the cabinet. When plugged into the right jack, it splits the cabinet into a stereo configuration with each jack requiring a 4 ohms nominal rating. If you plug into the right jack you will split the cabinet and only two speakers will operate which allows you to also plug into the left jack with a different signal for a split stereo cabinet. Also, if you're ever interested in selling the cabinet please let me know - I'm interested. 602-430-3936 Thanks