iFixit - Answers With Device "Musical Instrument Accessories"

Guitar Amplifier: Hum from SS AMp

Mon, 29 Dec 2025 17:01:33 -0700

I have a danville amp which when a Boss GT100 is plugged in creates a loud hum, but when a guitar is plugged strait in there is no hum, I have also tride send /recieve input

Using my Fender , there is no hum whatso ever

⟐ Commented December 29, 2025 at 17:01 MST

Guitar Amplifier: My line 6 amp comes on but no sound

Mon, 15 Dec 2025 02:05:04 -0700

Not to long ago I went to play my guitar with headphones on .well I plug my headphones in the Head phone jack well it ended up getting stuck and broke off inside the headphone jack. On the amp but I got the piece out but now it powers on but no sound so please some one help me

⟐ Edited December 15, 2025 at 2:05 MST

Korg nanoKONTROL2: Channel 2 cuts volume occasionally.

Thu, 13 Nov 2025 09:25:43 -0700

Sometimes radar drops volume in half . Touch it and comes right back.

Alesis SR-16: How do I diagnose this motherboard?

Sun, 03 Aug 2025 04:40:47 -0700

Hi, I would like to repair this Alesis SR-16. I powers on but there is only a slight display output, the LCD somewhat illuminates but it does not display any characters. When I plugged it in for the first time, it displayed some gibberish however. There is also no sound output.

I do not have any experience with repairing a motherboard like this and would there appreciate your help.

⟐ Commented August 03, 2025 at 4:40 MST

Zoom V3 Vocal Processor: Tune keys not working

Tue, 10 Jun 2025 11:29:15 -0700

Hello,

I need your help in figuring out how to repair my zoom V3 Vocal Processor. The knob to change keys isn't working anymore. I had it checked and they told me that there was an issue with the potentiometer and there isn't any compatible replacements here in our country. Can anybody help me with workarounds? Thank you!

⟐ Commented June 10, 2025 at 11:29 MST

Marshall MS-2: Marshall ms2 lets out sound only when I put it on OD

Wed, 04 Jun 2025 09:09:07 -0700

Hi so i have a problem - my marshall only turns ON when switching to OD. It’s like the OD option doesn’t exist. When i switch it to ON guitar doesn’t let out any sound. When on OD it’s like normal guitar - no electric sound. is there any way to fix it?

LINE6 HELIX FLOOR: Line 6 floor freezes and stops operation

Fri, 04 Apr 2025 01:38:53 -0700

My unit will operate properly for approximately 15 mins then freezes. Reboot will allow operation again but only lasts approx 15 mjns

Rogue G10: Why am I only getting static from my amp when I turn it on.

Fri, 25 Oct 2024 08:12:56 -0700

I used my amp with my acoustic/electric guitar, which has batteries in it for power. Now, when I turn it on, it only produces static. No other response.

teenage engineering ob-4: OB-4 Speaker Replacement Part

Mon, 23 Sep 2024 14:52:21 -0700

One of the speakers broke on my OB-4. Is there a place where I can purchase replacement parts? I spoke with TripleService in New Jersey and they don't repair OB4 only OB1. I love my speaker so much I'm sad that I haven't been able to repair it.

midi controller keyboard 61 keys: controller fails to power up

Tue, 20 Aug 2024 11:43:52 -0700

I have three identical 61 key Behringer UMX midi controllers that I used to build a home digital organ and the first one I bought years ago, but used sparingly, had been playing up for some time and now has given up the ghost completely. It does not power up and MIDI-OX software fails to see it. I swapped the board with one of the others. The keyboard now works but the other one with the defective board now fails to play - so it must be this board which is at fault.

This is the instrument when I was still building it.

It has been very difficult to find a replacement of its main board and buying another is a bit out of my budget. Behringer also no longer produce this type anymore and I do wish to preserve the aesthetics of three identical keyboards (keys don't all look the same between different makes). Online, I found keyboards that are horrendously expensive. Locally the only one that seems to suit me best and the cheapest I could source is Eur145.

I tried to identify the culprit component and thought it was one of the diodes as it showed readings both ways unlike the other 3 but on taking it off the board, which was not easy, it worked as expected. I tried soldering it back and not sure it is in place. :-(

I still have a damaged USB controller and now with two problems not just one.

Is there anyone who can help in any way to restore my organ back to its 3 keyboard layout?

teenage engineering ob-4: May I know if I can buy an OB4 antennae cable?

Thu, 30 May 2024 01:11:11 -0700

May i know if i can buy an OB4 antennae cable- the one that fits across the handle?

Lab Gruppen: Schematic or service manual for D40:4,D20:4

Sat, 20 Jan 2024 22:41:10 -0700

HI im searching for a schematic or service manual for the Lab Gruppen D Series D40:4 or D20:4

Fender Champion 600: Main Fuse blowing after nil use for a year.

Sun, 05 Nov 2023 02:22:06 -0700

My amp has been unused and sat in a cold workshop for about 12 months. When I powered it up, I hear a click and nothing. I check the main fust - and it is open circuit. I replace it with a slow blow 500mA as parts list, and it blows again. I have identified the load problem is on the transformer secondary circuit that feeds the diode rectifier section. I am a qualified electronics designer technician, but have no experience of this amp. Any ideas?

Roland TR-505: Low volume after turning on .

Mon, 21 Aug 2023 05:58:59 -0700

Hello There . I have a TR 505 that squeals when you first turn it on and then the volume drops . Someone left the batteries in it and they corroded the contacts and the DC adapter jack . Was wondering if that has anything to do with the low volume problem . Thanks .

Fender Frontman 15r: Replacing front panel mesh or all parts

Sun, 22 Jan 2023 04:42:39 -0700

Hi,

I am looking for mesh part, to replace the front panel of my frontman 15R.
Is someone find it somewhere ?

regards

Guitar Amplifier: G 15 GA DR Guitar Amplifier input failure?

Fri, 23 Sep 2022 09:15:17 -0700

I have a cheap guitar amplifier as stated above the model number but every time I put a lead into the input socket there's no sound coming from it no noises nothing I wonder if you could possibly help me in this***

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Fender 65 Twin Reverb: Tremolo Effect works then stops working. Is it the power tube?

Tue, 19 Jul 2022 20:50:35 -0700

I've tested the switch, used a shorted jumper plug. I know it's either the tube, optical-isolater or something else in the circuit. is it likely the tube? i've tried resitting the tubes, but the issue is that the circuit rarely works. Sometimes hitting the amp really hard fixes it. The effect will drop completely often and won't work again

Guitar amplifier: I have a line 6 spider jam amp,back lit on display but no text showing

Thu, 03 Mar 2022 05:03:39 -0700

I have a line 6 spider jam amp back lit on lcd but no text showing

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

Guitar Amplifier: JMF Spectra 30-T Sound Drop Out

Fri, 01 Jan 2021 05:13:07 -0700

The drop out issue starts after about 5-7 minutes of the amp being on and played. The sound doesn’t die out, it just fades and crackles, then comes back on after a few seconds. This repeats every minute or two. QUESTION: is this most likely due to old (35 years or so, I believe they are original) filter capacitors, and replacement of those is a likely fix? I’ve fully retubed, that didn’t work, I’ve cleaned the send/receive jacks, that didn’t work, I’ve look over the board and found one little plug that was a bit unseated and fully reseated it, that didn’t work. So now I’m suspecting it needs a recap. Does the sound issue sound consistent with failing caps? Many thanks.

⟐ Commented January 01, 2021 at 5:13 MST