R channel louder

Hi guys, wish to seek advice. Im using Marantz PM7001 int amp. My R channel is louder than my L. I have tried different source and still the same so i concluded is amp.

I measured it with spl meter from 20 cm away in front of the speaker with white noise. R channel consistently 2db louder. This throws off the center imaging.

The problem i face now, i dont know when this problem started, when i got the amp 1.8yrs ago or last week. As long i remember i had to slant my head to the left a bit more to get a good centre image. But i thought it was due to room cos it was closer to right wall. But last week, i forgot to turn off my amp and i covered it with a cloth to protect from dust, then turn off the main switch. The volume was set to 0. The next day, my sister turn on the main switch cos she wanted to use the computer, then the amp powered on under the cloth. It remain on for 4hrs b4 i noticed. I removed the cloth and off the amp cos it was so hot, but i can still touch it... took 20min to cool back down b4 i dare to test the amp. Amp tested ok.

But i was still worried so i payed very very close attention to the sound b4 i realise it might not be my ear which is imbalance (i had a bad infection to my R ear a few years back that lead me to doubt my hearing sometime). This is when i decided to measure the L and R channel. When i use the balance control, reduce R in favor of L, wow i get a good image.

What i want to know is, is this normal in amps? as in not all amps have perfect L and R or that it can degrade in time. Is something broken or degraded in my young amp? Or shud i ignore it and continue to just use the tone control to balance the channel.

Thanks.

have u tried to change yr spks from left to right? might be yr spks faulty....

If All not work. Try to reposition back your balanced L/R volume, maybe you can try take out your balanced knob from inside and reposition, and adjust to right sound. I'm try before with my arcam delta, and its work. Might have dust, try clean. at all end not workout asked for professional serviced.

If I were you, I would pay a bit and get the amp properly checked.

Em, i have tried with 2 different speaker. Same prob.

Hmm, im not good in electronics or DIY, i think i will go get a quote on how much is checking fee.... but after thinking long and hard... i think the amp been this way since day one. Just tat i always tot is my ear problem or room problem. And never thought about it till now.

But there is no distortion, noise, or funny sound in my amp, when i get the balance right.... its nice. Im just not happy that my amp isnt perfect, as im very protective of it

If i were you i just balance it right with the balance control. That is the purpose of the balance knob. If it is not broken do not open the amplifier. When it does ask the technician to look at your inbalance issue.

If the amp is from a reputable manufacturer, then it should have gone through at least the basic QC. Given that, it is highly unlikely that it will play with a channel imbalance. This means there is very likely a problem with the amp, perhaps some component is starting to fail, or hopefully some more trivial problem like bad contact or bad soldering joint etc. This was the basis for my suggestion.

oic, i think will get it checked. hopefully its not too expensive.

does hifi shop charge checking fee, or they only charge if there is repair/parts replacement? (noob here)

Yes, almost all of them do. If not, they will become a free checking center.

If they do not charge give them some kopi money lor. Make friends with them maybe later on can be free. Some have families to feed, place to rent, utilities bill, pay their workers and lastly amortised their test gears.

Ask how much diagnostic fee first before proceeding.

have you tried different interconnects between source & amp?

How about crossing over the interconnects from source to amp. The problem could also be from the source.
output ..... ... input
CD left --------> right Amp
..... right ------- > left

Better confirm the source of the fault, like swapping ic and speaker cable from L to R. If it's indeed the amp fault, better send back to sole agent in malaysia for check out before smoke coming out from the amp(possibility). Unless you are looking for excuse to upgrade.

Ok, last night i swap the speaker cables L to R, by right, L shud be louder now, but when i measure with spl meter, R is still louder o.0"

Then i realise, maybe the fan from the pc which is near the R speaker influence the meter, so i check the spl with no sound from the speaker and indeed the R side got noise from pc =__="

I think the solution to my problem could me reposition the speaker a bit further from Right wall. Because my speaker is not dead centre in the room, the Left side is around 1.5m further compare to Right wall.

If you have swapped speaker cables and the right side is still louder, then it is obvious that the amp is not at fault. Rather, it's the position of the speakers that's causing it (like you have finally deduced).