iFixit - Answers With Device "Guitar Amplifier"

Fender Frontman 15r: have frontman 15g.is power switch my problem?

Thu, 29 Dec 2016 04:44:16 -0700

bought used from thrift store. Looks new,but when I turn it on it hums even with all of the dials turned down. And if I plug in my cord it starts popping.I don't know whats wrong exactly.I'm thinking power switch?

⟐ Answered December 29, 2016 at 4:44 MST

Peavey VK100: Guitar Amp not turning on...

Sun, 27 Sep 2020 04:26:48 -0700

Peavey Valve King 100 doesn't seem to be getting power...no power light or any kind/type of sound. Have checked power cord even tried different ones. Have checked electrical outlet, even tried different ones.

Amp got turned over while playing, but wasn't dropped. It did break input jack, but was still able to play through it.

It started blowing outside fuse beside power jack on back where electrical cord plugs in. Took all of tubes out and systematically replaced one at a time until found the one blowing fuse. Amp worked for a while at home, but when I took amp out to friends house to practice with band, it just died...stopped all together, and wouldn't power up any more.

Can't afford new amp so advice to fix it will be deeply appreciated.

Thanks,

Keith

⟐ Commented September 27, 2020 at 4:26 MST

Guitar Amplifier: Looking for parts to Vox Valvetronix VT20X

Sun, 10 Jan 2021 12:14:59 -0700

So a drunken friend of a friend fell on my Vox Amp and broke off the power supply at the amp. Its a small chip labeled "KLM-3507". I've managed to trace down that this is a KORG manufactured PCB. The issue I am having is finding anyone locally who works on amps that can help me track down a place to order this part.

Hoping someone out there may be smart enough on VOX or KORG amps to let me know either where to order this part from, or if I am missing something about the part number and there is another chip I should order. Final option, if someone knows a good way to jerry rig a new and possibly more robust power supply that would also be more advisable than my current "make it a coffee table" option.

⟐ Answer edited January 10, 2021 at 12:14 MST

Fender Frontman 15r: I have a broke 1/4 inch input jack

Wed, 11 May 2016 09:05:04 -0700

My son accidentally turned amp over & broke the input jack. where can I get a input jack& is this a hard fix?

⟐ Answered May 11, 2016 at 9:05 MST

Fender Frontman 15r: Channel switching button seems to be having poor contact/broken.

Sun, 04 Aug 2024 15:59:05 -0700

When attempting to switch to the drive channel on my amp, the button seems to be having a contact issue. When I press it to use the drive, the sound doesn't come out, or when it does it sounds like when a cable is having contact issues. I know the issue is on the button itself because sometimes when I press it on a specific way, the drive channel works without issues, but after playing a while, I assume the vibrations move the button out of the good position because it goes back to the same issues as before. What's the best way to fix that? Should it need replacement, how do I go about looking for a new one? Replacement parts for amps seems hard to find.

⟐ Answer accepted August 04, 2024 at 15:59 MST

Guitar Amplifier: Crate GFX 212T amp sound cuts out

Tue, 09 Jul 2024 09:11:41 -0700

The sound cuts out on my Crate GFX 212t but returns with pressure on any control knob or bumping the amp. I'm thinking loose solder joint but not sure where to start.

⟐ Commented July 09, 2024 at 9:11 MST

Fender 65 Twin Reverb: Need Help Replacing a 240v Mains Transformer - RESOLVED

Sun, 14 Jan 2024 01:15:53 -0700

So I need to replace the mains transformer in this amp. It is a 240V primary power. The new transformer wire colours do not match the schematic I have and I am having difficulty identifying which wires on the primary side go where. I have the secondary side nutted out. Appreciate some help with the primary side. Cheers.

Pictures attached

Hey guys - I contacted Hammond - the maker of the transformers, and he gave me an updated wiring diagram. This coupled with a mate working out which primary wires go to which jumper sorted the problem and the amp and its new transformer are on speaking terms. Big thank you to all who contributed to this thread. Cheers, Rhea deLascy-Wells.

⟐ Edited January 14, 2024 at 1:15 MST

Guitar Amplifier: knobs crackle and pop

Wed, 23 Feb 2022 11:39:01 -0700

old peavy amp.. knobs crackle and pop

⟐ Comment deleted February 23, 2022 at 11:39 MST

Guitar Amplifier: Change xlr speaker outs to 1/4" speaker outs?

Fri, 01 Jun 2018 07:21:01 -0700

This vibration technologies sl140 is a solid state slave amp. There are two xlr (microphone) cable speaker outs that I want to switch to 1/4" jacks.

The 1/4" jacks have three pins on the back.

The xlr jacks are also connected by three wires to the circuit board.

The xlr jacks also come out of the amp as 8 ohm and 16 ohm and are wired accordingly within(3 wires).

I understand I only need two wires (+ and -) to wire up the 1/4" jacks and I'm handy with a voltmeter to determine what pins are center or not but the xlrs and internal wiring of the amp are throwing me.

My thoughts are two of the wires are the same (either hot or ground) and the lone wire will be the other. Determining which is hot or ground in the amp is a problem.

The wires are colored and I am planning on opening up to see the board and what's what but was kind of hoping for someone who may know a thing or two to throw a bone my way. I was hoping it would be quite easy to do.

(Couldn't find a schematic, info or an active number for this company.)

Thanks

⟐ Answer accepted June 01, 2018 at 7:21 MST

Guitar Amplifier: Loud noise only when input in

Wed, 18 Sep 2024 11:48:36 -0700

New to these devices (this is a Peavey Vypyr VIP 2) and I have no idea what is causing it. I see multiple things that look wrong but nothing I can definitely say is causing the issue and it honestly looks like someone else opened it and did stuff before me. Any ideas are appreciated.

Edit: new issue, whining with no volume on, loud noise when volume on. New better pictures and new video

Edit:

⟐ Commented September 18, 2024 at 11:48 MST

Fender 65 Twin Reverb: Dead Normal Channel - No Sound at All.

Thu, 25 Jan 2024 21:06:21 -0700

Hi - yes its the same amp which had the transformer issue. This time, in spite of the new transformer, the normal channel is silent. No sound when I plug guitar in. Here is what I have done so far. Aside from the transformer, I have also replaced, the filter caps, all tubes, retensioned the tube seats, cleaned seats, pots and jacks. The only sound I will get is when I run the guitar lead across my hand. Note, the guitar and lead works perfectly on the vibrato/reverb channel. What have I missed?

⟐ Commented January 25, 2024 at 21:06 MST

Fender 65 Twin Reverb: Dead Channel on Fender Twin

Sat, 13 Jan 2024 23:51:47 -0700

Fender Twin Reverb (re-issue) clean (or normal) channel not working. All tubes have been replaced - to no avail….what do I check or need to repair/replace?

⟐ Commented January 13, 2024 at 23:51 MST

Fender Champion 600: Side black chassis screws

Fri, 11 Nov 2022 02:08:03 -0700

I bought this amp with only one side chassis screw (black one on the picture attached).

I’ve been searching all over the internet trying to find one available for purchase but failed to find any. Also I don’t have anything to measure the thread, so can’t find an alternative. If any of you guys know where to find one of those screws or anything similar - I’d greatly appreciate it 🙏🏻

⟐ Commented November 11, 2022 at 2:08 MST

Marshall MS-2: Micro Amp Battery power not working.

Sat, 07 Dec 2019 11:11:23 -0700

My MS-2R micro amp by Marshall has never failed me in the past but I recently noticed that when I try to use battery power it doesn't work. The wall input works and sounds fine but the battery power doesn't work. I have replaced and used at least 3 different batteries but still no solution.

please help, have a nice day

⟐ Commented December 07, 2019 at 11:11 MST

Guitar Amplifier: no power on fender princeton 112 plus

Mon, 26 Feb 2018 19:04:45 -0700

I turned on my amp and no power. Have checked on/off switch, (good), capacitor, no power coming out. (Basler BE 2526901, PO 29668; 695-9801; no longer listed on company parts charts).

Does anyone know a replacement part for this part? Amp selling in my area is going for $130.00 or so. Is it worth trying to fix?

Thanx

⟐ Answer edited February 26, 2018 at 19:04 MST

Guitar Amplifier: Why does my amp just hum when turned on?

Sat, 09 Jan 2021 07:07:04 -0700

I plugged my 120V amp into 220V outlet direct by mistake. (Forgot the Voltage converter). Amp would not power up. I opened it up, found the in-line fuse and replaced it. Now the amp powers up but just hums. Volume and pitch of hum do not vary with amp controls. I know I damaged something else. Any advice on where to start troubleshooting?

⟐ Commented January 09, 2021 at 7:07 MST

Fender Frontman 15r: what's the maximum wattage speaker it can handle

Thu, 01 Mar 2018 18:36:06 -0700

was wondering what the max wattage speaker the Fender Frontman can support while doin a upgrade

⟐ Answered March 01, 2018 at 18:36 MST

Guitar Amplifier: My 15W AMP is making a buzzy noise, what will the issue be?

Thu, 02 Nov 2017 00:28:04 -0700

I have a 15W AMP but is making a buzzy sound even when is not connected to the guitar and sometimes you can not hear the guitar went plying, I replace my cable. I have no idea where to start, please help ????

⟐ Answer unaccepted November 02, 2017 at 0:28 MST

Fender 65 Twin Reverb: Replaced power tubes, but one isn't working although it's good?!?

Sat, 09 Sep 2017 12:53:10 -0700

I've just replaced the old 6L6 GT power tubes for JJ's 6L6 GC. One tube didn't light up so I've switched position and the tube light up, but the other tube don't. I am guessing it's something to do with the socket, but I've tried the old tubes and all still work...

I appreciate your help on this, because it's a bit mind bending.

Thanks a lot,

Paulo

⟐ Answered September 09, 2017 at 12:53 MST

Guitar Amplifier: ¿why when I play with my amp for too long gets distorted?

Tue, 03 Mar 2026 18:45:34 -0700

basically when i played for 1 or 2 ours the red light above my FENDER HOT ROD DE VILLE 2 decreases its intensity and the sound gets an ugly distorted fuzzy sound

EDIT: i used it for about 40 minutes and it dosent turn on, not even the light :(

i checked the socket from the two big tubes and they look fine to me

i dont know maybe it's the connection that goes to the speakers? there is only one input being used, i dont know nothing about amps or circuits

⟐ Answer accepted March 03, 2026 at 18:45 MST