Marshall MG15FX audio input quality is very low

Hi

I just bought my first amp, Marshall MG15FX. Everything is ok except one thing: When I plug my phone to the audio input (the jack has iPod icon), it outputs the sound in very low quality, the sound some kind filtered or cutted off or something like that, there is almost no treble, mostly deep and low quality bass sounds. It does not matter using the amp's speaker directly or with the headphone, it is same. Is this a production problem or is that the best quality I can get with this amp, maybe its price scale, I dont know. I m suspicious about the jack input since there is no difference between the speaker and the headphone.

Any help would be useful.
Thanks.

 

I don’t have an answer for you, and what I’m gonna say may not have anything to do with your problem.

I have two Marshalls with line out jacks and one with a headphone jack,....and the sound quality sucks on all of them!

I also have an inexpensive, ($200), Bugera G5 Infinium with a phenomenal line out, and with a choice of a 2-12 cab or a 4-12 simulation!

Just saying,.....

 

I think its because youre trying to run full range music through a speaker made for guitars.

 

It's a guitar amp, not an audio amp. I'd never expect it to sound good when used as a way to amplify your phone.

 

I have a DSL 40CR that sounds like shit when you connect the I phone to it and it’s 5 times the price of the MG. They’re meant to play a guitar through. Get a good Bluetooth speaker not a Marshall MG for that. Marshall makes a Bluetooth speaker and it is friggin amazing. Marshall/Stanmore.

 

As the others have said, the inclusion of the line in is a low grade afterthought.
The sound quality will most often be poor.

Another thought is that if you have a protective cover on your phone that can sometimes prevent the cable jack from fully inserting into the phone socket.
When I use my phone for music in my car I have to peel back the phone case to get the cable jack in properly.

Oh, and welcome to the MF @Zafer Altun

 

After I read all the answers (thanks for that by the way), I want to say ... too.

 

Well You could be right but I m familiar with electroinics, I m an engineer and this is so silly, because even though you have only one channel (so one speaker), you can combine the stereo channels on it. This does not affect the sound quality, but the effect we expect.

 

It does not matter actually. As I said, I m an engineer, I have some electronic stuffes, for example I tried the cable with a very tiny speaker that I desolder from a toy (which is 0.25W!!!) and there was no sound loose, you can still hear it clearly except the bass sounds ofcourse, since it is only 0.25W.

 

But it is so ridiculous since it could be solved with simple electronic components. Even so cheap devices can do it, I bet even $1 device such as tap and listen pocket radios can do it. I cant find a word to say to Marshall. I have Major II headphone, I was happy with it, so thats why I choosed as amp brand, but now my thoughts changed.

 

Now I never suggest Marshall for the amps, never.. I cant understand how they take a risk for the brand name just because of a simple things such this, they have to shame!

 

A guitar amp is engineered to have a very NON-FLAT frequency response. Make up or buy a cable that lets you plug your guitar into one of your RCA input jacks on the back of the stereo and you'll hear how weak and boring your guitar sounds when it's played into a flat frequency response system.

I may not have a sheepskin that says EE on it but I've been doing electronics repair for 35 years now. Every type of product from analog audio amplifiers to digital avionics.

Guitar amps are not amplifiers in the general audio sense. They are artistic sound creation devices, with a frequency response characteristic that is anything BUT flat. They are engineered to make a guitar sound GOOD, which takes a lot of equalization. And of course, they have power amplification features as well, anything from as little as 1/10th of a watt up to as much as 200 watts, or in some cases, even more.

 

As a summary, I m dealing with complex electronical circuits, no one can explain me it is just for the guitar, and thats all. Its solution is simple. Now if I open the device box, the guarantee will be invalid. So, I better sell it although I just bought, get a new one, or, to modify it wait for some quality audio input for 2 years!!!!!!!! Thanks Marshall...

 

It's made to be used with a guitar. If you want to amplify the output from your phone, you've got the wrong product for that. It won't sound good in that application.

 

It isn't a fault or some sort of deception on Marshall's part.
These amps are not supposed to be P.A. quality sound systems.
They are guitar amps.
The line-in is purely a practice tool.
There has to be a compromise between which gets the correct EQ'ing.
Guitar or line-in?
My choice is always going to be the Guitar.

There is no point getting angry about it.
Just play your guitar.

 

Well ok, if I need it in real quality, I get a mixer or something like that already, that is not the problem, agree. What I m trying to say it the solution could be simple and cheap by just adding some extra components, thats all. I m using my guitar at home but why I just cant practice with the musics that I preapred in computer or on the phone pratically. It is a simple need, should I have a mixer at home? Absolutely no, I m using it with my headphone already, but as a human, naturally, the expectation is a bit higher than what it is.

 

I've been playing guitar since 1985. I never at any time expected a guitar amp to work for high fidelity applications, or for a high fidelity amplifier to work well as a guitar amp. I never had any such expectations. It was evident to me very quickly that they're two different sounding things.

You can get simple, compact mixing consoles for under a hundred bucks. Lots of choices in that price range.

To make that guitar amp work for more of a high fidelity application, you wouldn't add components, you'd remove them. There are equalization circuits built into the amplifier design that you'd want to bypass. But then a guitar would sound weak through it.

 

I m not analog expert but it seems make sense, thanks for the replies.

 

I've had an MG15 for over 10 years and never used the Aux In. Get some Grado Sr60 headphones for the phone. They have open air design. Mix in your ears. Cheers.

 

Get a Code. 100w bluetooth speaker. I have the 100h + 2x12 and a 25c at my office for down time jamming.