bleader wrote:
Hi there,

I've got a marrantz SR 4003 at home, which seems to go easyly into
protection mode.

First the setup:

- Marrantz SR 4003
- Jamo S606 HCS (5.0 setup), columns have passive "sub"
- no active sub
- optical input, raw dts soundtrack sent to the device

When watching movies on this setup I found that without an active sub
basses were a little weak, so I pushed the bass to the max (+6dB IRC).
I was watching a movie at -30dB (not that much on a range of -81/+15),
and at a point where there was quite some bass, the marrantz went into
protection mode. From the documentation, there are 2 different
protection modes, this one (8 flash per second) being the one where
you're supposed to bring back the hardware to the store for repair.

This is what I did, but curious as to know if the issue was solved, I
tried the exact same setup when it came back from the store... and the
same thing happened.

Now it's once again back from repair, but I'm not very keen on trying
out yet again without knowing how to reset the protection by myself.
Warranty runs out soon, and I don't really want to bring it back to and
wait the 3 weeks they take to send it back and forth to the proper
repair place.

So here I go with the questions:

1/ Does anyone know the get out of protection mode procedure for this
model ? Is it some kind of switch to reset or fuse to change, or is it a
more complex procedure ?

don't overload the amp. From what I can tell, it's rated 80watts per
channel into 8 ohms. The spec sheets shows 6-8 ohm is acceptable, and you
have 6 ohm speakers. Driving the bass up will either burn it out or send
into protection mode.

I've not ripped the amp apart so I can tell you how it's reset or fixed.
Running the bass turned up into all the channels will draw quite a bit of
power, as it's pretty close to just passing DC into the speaker, and the
current draw can be pretty high. Years ago they'd just put a fuse on the
rear you could replace yourself. Easy "service" and "repairable" are a
forgotten concepts these days though.

2/ Any idea why this happens ? My Jamo are 6ohms, but the SR4003 is
supposed to support it (as 6ohms output power is provided in the
specifications). I listened to music or watched movies without any
problem prior to this, even quite loud.

see above. turn the bass down, get a separate speaker or get a giant amp.