#1
So as I got a new Jvm410h the first problem is the number of inputs and cables. I got like 7 cables in total and the instructions are just bad. I'm guessing that these two identical cables are for the stereo/mono inputs in the cabinet (no idea what 4ohm or 16ohm mean). I have one of the cables in 4ohm at mono in the cabinet. Now should I plug the other end into 1x4ohm or 2x8ohm in the amplifier? There are a total of 5 outputs 1x4ohm, 1x8ohm, 2x8omh, 2x16ohm and 1x16ohm. Why is there another identical cable that seems to be for the same purpose? And why did I get a sssnake cable with the bundle I bought (a short one)? I can't seem to find any use for it. So far I've plugged in the footswitch and the main power cord ( whatever you call it).

Why is this so complicated? D:


Just lock this.
Last edited by Billie_J at Nov 22, 2016,
#2
Quote by Billie_J
So as I got a new Jvm410h the first problem is the number of inputs and cables. I got like 7 cables in total and the instructions are just bad. I'm guessing that these two identical cables are for the stereo/mono inputs in the cabinet (no idea what 4ohm or 16ohm mean). I have one of the cables in 4ohm at mono in the cabinet. Now should I plug the other end into 1x4ohm or 2x8ohm in the amplifier? There are a total of 5 outputs 1x4ohm, 1x8ohm, 2x8omh, 2x16ohm and 1x16ohm. Why is there another identical cable that seems to be for the same purpose? And why did I get a sssnake cable with the bundle I bought (a short one)? I can't seem to find any use for it. So far I've plugged in the footswitch and the main power cord ( whatever you call it).

Why is this so complicated? D:


Just lock this.
Well you need to. If you have the big-boy equipment you need to know how to use it. If you do something wrong you can end up destroying your cab and/or amp, likely both. You are asking now so that is a good start.

What cabinet model is it exactly? You should be able to just use the 1x16 ohm output from the amp into a 16 ohm mono-input cab if it is rated for 100w or more. When in doubt, manual.
Last edited by Will Lane at Nov 22, 2016,
#3
Quote by Will Lane
Well you should. If you have the big-boy equipment you need to know how to use it. If you do something wrong you can end up destroying your cab and/or amp, likely both. You are asking now so that is a good start.

What cabinet model is it exactly? You should be able to just use the 1x16 ohm output from the amp into a 16 ohm mono-input cab if it is rated for 100w or more. When in doubt, manual.


Mr1960 av. I already did the mono 16ohm to 1x16. Never used tubes before so I guess the heating of the amp is normal? What do the outputs like 2x8 and 2x16 mean? And also a side question. The amp keeps buzzing with my guitar plugged in. Once I touch the strings it stops but if I don't touch anything the voice keeps going on. Not sure if normal. I could share a recording if necessary.
Last edited by Billie_J at Nov 22, 2016,
#4
Quote by Billie_J
Mr1960 av. I already did the mono 16ohm to 1x16. Never used tubes before so I guess the heating of the amp is normal? What do the outputs like 2x8 and 2x16 mean? And also a side question. The amp keeps buzzing with my guitar plugged in. Once I touch the strings it stops but if I don't touch anything the voice keeps going on. Not sure if normal. I could share a recording if necessary.
I think that is probably best unless you wanted to run another separate cab, which you do not really need to do. Switch the cab to Mono, use the 16 ohm input, use the single 1x16 ohm output of the amp, and you are set.

The other inputs are for cabs rated of different impedances (which is measured in ohms), and also for dual-cab operation. 1x4 ohm or 1x8 ohm is for a cab of 4 or 8 ohms, respectively. 2x8 ohm and 2x16 ohm are for a dual cab setup. I am not sure if Marshall meant you have 2 8 ohm cabs (or 2 16 ohm cabs) or that if they meant two cabs that together EQUAL 8 ohms or 16 ohms. Impedance can change when two speaker loads are hooked up certain ways. If two 8 ohm loads are together in series, then the two numbers are added together- 16 ohms. If two identical ohm loads are together in parallel (we will say 8), the number is halved- 4 ohms.

However that is me talking without looking at the manual, Marshall could have labeled their outputs weird. Anyway, just use the output and input as I listed above. In fact, I would put a strip of electrical tape over the other 4 outputs so you do not accidentally plug the speaker cable into one of those other outputs.

Yes, tubes do produce heat. Give it some room for ventilation. It should not be so hot parts of the cab start melting, though. Nor should your tubes be "red-plating", which is exactly like it sounds. They should glow but not be bright red.

Noise from your guitar like that is normal. Especially if you have a high-gain setting and/or a lot of electromagnetic interference (cellphones, lighting, etc.), you will get some noise into your signal. Even more so if you are using single-coil pickups.
Last edited by Will Lane at Nov 22, 2016,
#5
Basics: Plug your cabinet into the head using ONLY a speaker cable. Never use an Instrument cable, or you could damage both the cable and your head.

Once you've figured that part out, select the head output that matches the impedance of the speaker cabinet. If you have an 8-ohm speaker cabinet (just one), plug that into an 8 ohm output on the head. If you have more than one speaker cabinet, THEN worry about the "2x__" outputs. RTFM!

Then plug your guitar into the cabinet using an instrument cable (and not a speaker cable). You might want to label them; a piece of tape on each end will do.

THEN plug your head into the wall and turn it on.
#6
What about the sound that sounds a bit like a pitch harmonic (Idk how to better describe it) which usually grows the closer you go to the cabinet. A high pitched sound it is
Last edited by Billie_J at Nov 22, 2016,
#7
Quote by Billie_J
What about the sound that sounds a bit like a pitch harmonic (Idk how to better describe it) which usually grows the closer you go to the cabinet. A high pitched sound it is
That is feedback. It is the result of the sound from the amp going back into the amp again through your pickups.