JMD Attenuation

[Sully]

Although I've played Marshalls for years, I've just recently bought my first attenuator. Its a TubeJuice 50w, which are fairly new and handmade by this guy. It has an 8ohm and 4ohm switch on it.

I've used it on my Vintage Modern into a 2x12 cabinet that is 8ohms, so naturally I set the head to 8ohms and the attenuator to 8ohms and into the cabinet. Sounds great.

Now that I have the 50w JMD and an old beat up 1960A cabinet, I'd like to know how i can still use the attenuator. The 1960A of course runs at 16ohms mono, and 8ohms stereo, and the JMD will do 8 or 16 ohms. My attenuator will only do 8ohms or 4ohms.

So the question: What do all 3 need to be set at to use my attenuator with the JMD and my 1960A?

[guitarest]

JMD is 16ohms

[Sully]

That doesn't even make sense.

You can use both 16ohm and 8ohms outputs.

[surfnorthwest]

Well ideally you want a 16ohm attenuator so it matches the cabinet.

But what you will need to do is on the back of the JMD you can go from one of the two 8ohm speaker outputs into your attenuator then into your 16ohm cabinet (mono). Now while the presents a ohms mismatch it won't hurt the amp going into the 16ohm cab.

I have to ask why a attenuator though, the JMD more then any other Marshall can rock at low volumes. Even if you have the gain and preamp driven with the master set low should still be giving you acceptable tone. Nothing personal but I am no fan of traditional attenuators, I f'ing hate them. If you must use it or like it perhaps you might contact the seller and trade it for a 16ohm version.

[Sully]

Thanks surf. Yeah the JMD is a good low volume amp, but if you get the preamp and master volumes to about 12 o'clock the power amp really starts to make a difference in the tone. It really fattens up a good bit. I know you're not a fan, but I've always had good luck with them and have never had much tone loss from the ones I've used at least. I may not even use it, I just wanted to make sure I wasn't hurting anything. Thanks for the response.

[noise5150]

I tried a few attenuators with my DSL and found I didn't need one. However, I have a JMD and I could be wrong but are you supposed to use an attenuator with a "hybrid" amp??

[surfnorthwest]

Why not, preamps (digital or otherwise) have nothing to do with attenuating the power section. A attenuator can be used on the JMD.

[noise5150]

Ok so I did ask and it turns out that using an attenuator on the JMD is fine!