Just an update on the Pioneer GM 6100F 600W amp.
Seems to be a really nice amp SQ wise guys. I played my Phil Colins disc on it, the album with In The Air Tonight, and have already noticed a stark difference in audio quality compared to my old Kenwood Premo deck.
This disc has been mastered beautifully. On one track I can hear an extra instrument that I never heard before. It was actually masked by the vocals on the other deck, but I can hear this triangle overlapping the start of the backup vocals. Another thing that sounds better are the piano's. The attack and timbre is brilliant.

Although I can't hear hiss when music is playing, I still need to know if hiss when there is no volume is normal. This hiss isn't overly amplified, just there in the background with vol down, no music playing. There's also a little noise from the Kenwood 2 din unit. But I think this is to be expected with a flouro. cathode based TFT screen.

Is the hiss from all speakers Kit, or just one/several?
I have no hiss in mine now, running from a Pioneer HU, but when I first installed the amp, using Speaker level inputs on an older headunit, I had an annoying alternator hiss from the rear left.
It was fixed when instead of using the speaker wiring in the ford harness, I ran it some new stuff.
Is the hiss a set frequency, or does it change with engine revs?

No nothing like that, just very low background hiss. Can't hear it when the musics on. You have to put your head close to the speaker to hear it too.
It may be that all solid state amps do it, might be that I notice it because in the car all the speakers are so close to you.

That is the overall noise floor of the system. Your right certain screen power supplies carry a certain amount of noise with them. With the Alpine unit in PYROLY you can turn the display off and continue the unit running so there is no screen power noise. In my car the screen power supply is on a fly lead remotely mounted 80cm away and you can also switch off the screen.

Also depends on the amount of voltage your supplying from headunit to the amps and how far the amps gains are turned up. I had 400rms per side available to my front stage in my car and hence had gains at 0 and then fed them a nice strong 5v input to ensure the amps were just ticking away.

I have never had any noise through any of my systems PYROAY or PYROLY with the system powered up and with or without music playing.


I don’t know how much noise your getting but based on your description it seems very faint and not like a real problem.

Thanks mate. Your knowledge is much appreciated on these matters. You help make the audio forum a very interesting place to be.

Cheers, and hurry up with that sound deadening doco

Thanks i'm glad it''s appreciated,


I would love to rnu an SQ workshop covering all these maters followed by a test and tune but once again i'm sure there will be no interest like the other test and tune session.

Oh well maybe another day

Where can you pick one up?

Frasca Electronics in Sale is where i get mine but i can ship one to you if you like.

Otherwise Stylin distributes earthquake. Not sure where else...