Headphones mixup with randall amp

Hi everyone,

I recently started playing and was offered a randall RG200DG3 amp.

All is well, except that when ever I try to plug headphones on, as to not disturb the neighbours, I can only hear sound from the right side of the headset. (and yeah, I've tried with 4 different headsets, all working on other machines).


Please help


Thanks

I think you might have a problem with one of the output transistors - I believe you can have them checked at Radio Shack in order to find out

Good morning, and welcome to the forum!

Actually, I have been a Randall user for many years, although I will admit that I have never tried that particular model.

What makes me curious is that I do no remember ~any~ Randall amps (aside from a couple really tiny amps) having a headphone jack. They almost always feature a Slave, Pre-Amp Out, Line Out, or Loop In/Out jack.

By any chance, are you plugging your headphones into the Line Out Jack?

If so, there are two problems:

1) All the above-mentioned jacks are mono. So instead of the typical 1/4" TRS (tip-ring-sleeve) STEREO headphone jack, it is a 1/4" tip-sleeve MONO jack. (This is the normal guitar plug you use.)

So while you ~can~ physically plug the headphones into one of these jacks and hear something, it will always be in one ear.

2) Line out, Slave, and Loop jacks are not designed to power headphones.

This is a problem because the voltages and currents on these jacks are what are called "line level" voltages. (More technical detail on this: http://en.wikipedia.org/wiki/Line_level)

While you ~can~ listen to line level signals with a headphone, to the output circuitry you are effectively almost shorting it out. Line level drivers expect approximately to see a "resistance" of about 1k (kilo-ohm) when plugged into the Line Input of another device.

Headphones are anywhere between 4 and 50 ohms... Very close to a short circuit.

While I have never seen this physically damage a pre-amp, I would not recommend using headphones on a line out.

So, what to do?

If you have a stereo, boombox, or computer that has a "Line In" jack, you can go to Radio Shack and get a few adapters so you can plug in the line out from the Randall to that device and listen to it with stereo headphones.

If you are dead set on plugging headphones into a line out, you will need an adapter to convert the MONO 1/4" Line Out to a STEREO 1/4" TRS jack.

Lastly, if your Randall actually says "Headphone" by the plug you are using... Disregard everything I have just said and follow Copper's advice!

I have seen this happen more than a few times, and most of the time when someone is experiencing audio in only one ear of a headphone it is because it is being plugged into a Line Out jack instead of a Headphone jack.

Good luck!

Another thing you can do it buy or build a headphone amplifier so you can plug your headphones into any line out.

If you buy one, they are expensive. You might as well just buy a boombox or something.

But if you like fiddling with electronics, you can build one for about $20 or so in parts! Just google "headphone amp" and there are all kinds of schematics.

Here's a good starting spot: http://www.dansdata.com/cmoy.htm

Hi everyone!

If I want to use my headphones into a line out, what kind of adapter I need to get in order for me to convert the MONO 1/4" Line Out to a STEREO 1/4" Line Out TRS jack?

This adapter will work: http://www.radioshack.com/product/index.jsp? productId=2062464

But, like was mentioned earlier, you will likely not get the full sound you are expecting because line output levels are weaker than what is normally used to drive headphones.

So will this will ~probably~ work, I would advise against it.

Instead, plug a headphone amp into that line out.

Will this product work also, so that you can have the sound come out the amp and through your headphones too?

http://www.radioshack.com/product/index.jsp? productId=2103991

Trust me, you are probably going to run into problems doing that.

Some amps automatically disable the speaker output when you plug anything into the Line Out jack. If you ALSO have a Line In jack, you ~could~ use that adapter by plugging the headphones into one jack, and running a cable from the other jack back to the Line In.

But here's the problem: you are inserting headphones into your audio loop BEFORE it hits the power amp.

Not only will the degrade the quality of the signal (likely muffling it), but most headphones also act like microphones: you will probably get a huge feedback squeal.

I wouldn't recommend it...

WOW, Thanks for the info! I guess the first one recommended is the wisest choice to choose.

Somehow the adapter you recommended did not work for my amp. No sound came out. Why is that?

Here is how the back of the amp look:http://www.behringer.com/EN/images/lightboxphotos/ GMX212_P0211_Rear_XXL.jpg

Good morning, David

It looks like you already have a dedicated headphone output on the amp!

You should be able to plug your headphones straight into the "Phones" jack and be good to go...

If I place my headphones into the "PHONES" jack it will eliminate the sound from coming out the amp. Unless you are talking about using the adapter, you recommended, some other way on how you had wanted me to use it, but what I was hoping for the sound to come out the amp and the headphones by using that adapter you recommended.

Sorry, I must have missed that part where you said you were trying to get the headphones AND speakers going at the same time.

Headphone outputs usually do kill the speaker output.

Are you doing this for recording or something?

The best bet: run that line out into a headphone amp, or any other gear (mixer, boombox, etc) that has a Line-In and provides a headphone output.