New to amps, would like to make a purchase, don't quite understand the difference between dual & single channel amps. They both have two inputs on the front usually hi & low, and some have a "send" & "return" on the back.

Also, If one is using effects boxes, would they plug their guitar into one of the inputs in the front, and then how is the configuration for the effects boxes using the loop of send & return along with an adjustable knob, like on the Marshall Astoria Dual Combo?

What is the differences between using input hi or low on the front of the amp, and which one is better for maximum use of the tube overdrive?

Thanks!

Couldn't update on my mac, so went to my PC and still having issue running the software. How to I get the Code to update its firmware.

My JVM410C Combo which is only 7 months old has started making intermittent but persistent load crackling and popping making it unuseable. How should I go about getting this repaired or replaced under the warranty?

Hi, I bought a Marshall DSL40C amp in July from Gearnuts (www.gearnuts.com).  The amp has been working great until yesterday - a crackling buzz began and then I heard a pop and saw a small flash of light.  It looks like the tubes are blown out.  How do I get these replaced under the warranty?

Thank you,

Sean

Hi, what brand and model are the best replacement tubes for the jvm410c? I would like to have some alternatives to winged c el34 tubes?

Best Regards

would it be possible to do something like a phrase recorder in the app, maybe as part of the song player to capture/record ideas and riffs to save for playback to jam to or email to yourself as say an M4a.

Where can I buy the INPUT for my little Marshall practice amp (G 10 MK.II). The excisting input  has gone bad, cord does not plug in at all.....love this small practice amp, would like to get it going again..........Thanks

What is the FDD button located far right between

Fx level & CD input ? What is it's purpose? Thank you!

So...just got my new code 25 the other day and bluetooth hooked up great....played a couple of days and no problems....Tonight..cant get it to hook up.  Any ideas?...Can I ultimatley just hook up USB to my computer and adjust fromt there?

Hi there, currently using the marshall vba400 with the vbc412. Just purchased the DOD meatbox reissue and I was wondering what the frequency response is on the custom 12' speakers as I dont want to overload them with more low frequency than they can handle. 

Cheers,
Matt

P.s the cab is from 1999 if that helps at all.

When I try to install the firmware software I get an error saying Cannot start application. Application cannot be started. Contact the application vendor. I am running windows 10.  Any suggestions would be greatly appeaciated. 

Hello, I' m from Finland. Can you please tell me how many amps of these are made?  White label in the chassis shows "DARKNESS" , proto 1 , Serial number and EXAMPLE  # ?

In the power amp eq (gain, bass, mid, treb) control knobs do not work. Only the volume knob works. On the pre amp section, all eq  control knobs are working normally.

Is it normal  ?

While attempting to install the firmware update utility for my Code50, I continue to receive an error.  Are there any current issues with the the utility?  Perhaps the problem is on my end?  Please advise.  Thank you.

HOW CAN I DOWNLOAD THE FULL USER MANUAL FOR THE AMP AND FOOTSWITCH?

I just got a Marshall TSL 60 head and am having trouble with the footswitch.

Of the five buttons: Clean - Crunch - Lead - Reverb* - FX Loop*

The Reverb and FX Loop are both latching switches and work fine. The Clean, Crunch and Lead switches are all momentary and there's some sort of digital logic switching going on on the board. The problem is with these switches.

When I turn the amp on, the Clean switch LED comes on. When I hit the crunch or lead switch, nothing happens (No LED, no change from clean).

I thought it was an issue with the switches, so I replaced them. Now Crunch and Lead still do nothing, but when I hold down the Clean it switches to Overdrive for as long as I am holding the switch. When I let go, it goes back to clean.

Anyone have any thoughts why the switches aren't doing their job? Could it be a fried transistor that's supposed to be controlling the logic switching that's going on (Anyone know a good way to test this?). Some more info on the footswitch...

[Schematic](http://music-electronics-forum.com/attachments/34024d1432077935-tsl-20footswitch_page_2.jpg)

[DIN Pin Guide](http://i81.photobucket.com/albums/j202/paperboy38375/Forum Pics/tsl100switchinginfo.gif)

[Board Pic](http://i91.photobucket.com/albums/k288/fixr1984/DSCF0946.jpg)

[Another Board Pic](http://i281.photobucket.com/albums/kk224/chrisdrane/TSLInternal_zps056b5334.jpeg)

Hi, I have a JCM-800 all original and assume is 2013 made, the serial number is M-2013-05-0216-1, I like to know what brand and kind of transformer was installed in this specific amp, and if is able to support kt-88´s tubes?

Kindly let me know as to whether any differences in the amount of gain

between ASTORIA Dual and 1959HW when those are fully cranked up?

1959HW is much heavy in gain when overdiven? Thank you.

Recently, I have purchased thru Andertons Music U.K, for a stack of

ASTORIA Dual head and matchinf 1x12 cabinet.

M-2015-52-0008-1-112 and M-2015-43-0205-0  respective S/N

However, in the Registration column,you have not provided the amp model yet. 

Slow hand did you go since almost more than year has passed away from the launching

of the amplfier ASTORIA series and matching cabintes. please clarify.

I may be doing something wrong. However all the sittings ive tried all sounds muddy/ muffeled. I play alot of metal music and it just sounds a bit off. Could someone possinly help me?