Need help getting rid of annoying (volume) protection lock (1 Viewer)

[Bart_R]

Hi everyone,

Some months ago I got a new receiver, the marantz sr5600, with which I encountered a little problem just now. I was listening to my Two Towers soundtrack and wanted to crank up the stereo to fully envelop myself in those nice horn-sounds. However when the volume reached a certain level, the receiver timed out, displaying the word "PROTECT". Thankfully, it wasn't busted and came back on after a few seconds (during which I turned down the volume).

In a way, I understand that you cannot drive the receiver too high, but when the installation-guy (it was part of a price) tested the thing initially, it went way louder than it did now. I know my front speakers are up for it (dali concept 8) at the very least. Maybe it's a problem that I bi-wired my center speaker (mordaunt short) and attached an L-pad to the tweeter-wires? Other than that, I think this shouldn't happen.

Does anyone know how I could fix my problem? Is it the L-pad? Are my rears too small perhaps? (Dali concept 2)

Thanks in advance,
Bart.

 

[Alon Goldberg]

Bart,

It might be time to consider purchasing a seperate 2-channel poweramp. For instance, I see a Rotel RB-1080 (2x200W) on Audiogon for $650.

 

[Arthur S]

Bart

You should contact the installation guy and let him know of your problem. You should not need any new equipment.

Happy New Year

 

[Bart_R]

Re: Alon

Thanks for the tip. If I ever have the cash for an extra amp, I'll consider your suggestion. Right now, though, this is not an option for me. Besides, it's not really a solution to my problem. The thing is, this is not something that should happen as I'm not really pushing the receiver that hard. The volume levels aren't that excessive and it did better during the initial test.

Re: Arthur

Yeah, you're probably right. I'm just hoping I didn't damage anything by bi-wiring my center speaker and blocking some of the higher tones going to the tweeter with the L-pad.

And thanks. A Happy New Year to yoo too!

 

[JeremyErwin]

why are you using an l pad?

 

[Bart_R]

I'm using an L-pad because the higher frequencies of the center speaker sound too shrill for my tastes, so I chose to lessen them by blocking out some of them by connecting the tweeter wires to an L-pad. It works wonderfully, but I'm wondering if it's the cause of my little problem.

(Btw, I do have another center still [dali concept center, the one that came with the rest of the set], but while not exactly shrill, I do find them too high on the whole, and the bass is also lacking the depth/punch that I love about my mordaunt short. Hence, I opted for the ms/bi-wire/l-pad solution.)

 

[Jean D]

is the L-pad something you've added after the install guy left? If not, can you think of any changes you've made? if so, I would remove it and see if it happens again.

 

[LanceJ]

I agree with Jean: take the L-pad out of the circuit and see what happens. Those gizmos are supposed to present a constant impedance to the amp as they are adjusted, but one time when I was fooling around with one (using it to try to control the volume of my Hafler surround system*) as soon as I turned up my receiver to anything past whisper level, the receiver's protection system activated.

* an incredibly simple, cheap and (and depending on the source) very effective way to get surround out of most stereo systems. Do a google search and you'll get lots of hits.

 

[Bart_R]

Well, I just ran the receiver towards the same volume levels (-19, -18) without the L-pad and the original center and still the protection device kicked in. Damn, this isn't good. I think I'm going to need to send this one in for repair.

Is it an idea to look for defects inside by removing the top? Can I even spot such things as a layman?

Thanks,
Bart.

p.s. Oh and yeah, I did install the L-pad after the install guy left. Another thing I did was daisy chain two subs, but I already unhooked one, and no difference.

 

[LanceJ]

In my experience, with problems such as yours i.e. the gear works most of the time vs. it won't even turn on or there is visible smoke , usually the component(s) that are misbehaving look fine on the outside so special testing equipment is needed to determine the problem.

But if you do start poking around in there, BE CAREFUL! Even after a receiver is turned off and is unplugged from the wall socket, there can still be high voltages present, especially around the power supply section (in particular the filter capacitors - the large can-shaped gizmos [usually at least two] usually located near the power transformer. Capacitors act as temporary batteries and can hold hundreds of volts for long periods of time).

 

[Bob McElfresh]

Hi Bart.

Either one of 2 things is happening:

- You have developed a short between the + and - terminal behind your receiver or behind a speaker.

- Your speakers are drawing too much current from many minutes of low-frequency sounds.

Do a visual inspection of the speaker wire connections at BOTH ends of each speaker wire. Look for any stray strands of copper sticking out. If you have not done it in a year - try disconnecting each end of the speaker wire, trim off oxidized copper and re-connect.

True story: My Yamaha A1 started going into protect mode even at modest volumes. I inspected all the wires and saw nothing wrong. The problem continued. So I disconnected, trimmed and re-connected the speaker wires at both ends. Problem went away.

Your other option might be to define your L/R speakers as 'Small' so the receiver wont try to send subwoofer frequencies to these power-hungry drivers. Instead, it will route those sounds to your sub, or other LARGE speakers.

Try both and let us know what works.

PS: You might have to disconnect your center speaker, and run through the problem passage at loud levels to see if the problem goes away. Disconnect another and another until the problem stops. The last speaker you disconnected is now suspect. The wiring to that speaker may have a short, or internally the speaker has developed a short.

 

[Bart_R]

Re: Lance

Thanks for the advice. I'll be careful when I decide to open up the receiver, if I will even go ahead with this.

Re: Bob

Thanks for your solutions. They might help. I thought of the short-thing myself and saw a piece of wire actually touching the back of the receiver. So I fixed just this one bit but nothing improved. There are little bits of wire sticking out regardless, though, even though they are not touching anything. I don't know if this does any harm. But I'll try disconnecting everything, and stripping the wires all over again to see if the PROTECT-thing disappears. It's not been more than 4 or 5 months ago since it was all installed, though. But who knows.

I don't think the second thing is happening, since only my front speakers are set to large and they definitely fit that bill.

Thanks a lot for your input.

Regards,
Bart.

 

[Bob McElfresh]

These dual banana plugs are a great way to do a neat wire job:



Buy 1 set from Radio Shack and see if they fit the spacings on your reciever or speakers. (The spacing of the binding posts is NOT standardized). Just strip a short amount of wire, shove in the side hole and screw down the back.

If the spacing does not fit (or the dual plugs stick out too far for behind your receiver) These single-bananas work great:



With these: un-screw the bottom part, thread wire through the middle and fold the copper strands over the lip. Tighten on the banana part and you have a neat, strong connection.

The Shack has these, but you can also get similar ones for a buck or so cheaper from places like www.partsexpress.com

 

[Bart_R]

Hi again, Bob,

Thanks for the plug-suggestions. I don't have a radio shack here, but I'm sure I could find the plugs somewhere.

Still, I'm not sure if they'll benefit me that much since the plugs on the back of my receiver more or less work in the same manner.

A question, though: should I make it a point to let the wires disappear completely into the plugs, so that no (or hardly a) wire is even visible, or doesn't this really matter so long as the wires don't touch each other or the back of the receiver?

Anyway, I have now unplugged every speaker except for the fronts (and sub) and there's no problem. I've turned up the volume so much as to made the whole street rumble and not a single glitch, so that's good. I'm thinking it could be my rears since those horns I mentioned sounded much higher coming from those speakers (that great, natural sound I was loving so much). But I'll continue with the testing. To be continued...

EDIT: tried it with the center (the one with the L-pad) and: no problems yet. 4 more speakers to go... (I got a 7.1 set-up). EDIT 2: the (first pair of) rears working fine too! Sigh, number 6 and 7 now...

Cheers,
Bart.

 

[Bart_R]

Well... it's definite now: it's the second pair of surrounds that causes the problem. Everything else works fine, but when I finally attach these two babies, the receiver goes into PROTECT again at the previous volume levels. And indeed, I added these two speakers after the installation guy left so it makes sense the problem didn't occur earlier. And I guess I just never pushed my receiver that hard again after the initial test.

So now there's the obvious question: what exactly is the problem with these speakers? Is there no way I can use these at high volume levels or do I just have to change some settings or what not? I mean, they're silent in 5.1 encoded material anyway, but I like their activity in prologic mode (i.e. simple analog/stereo sources). Surely there must be a way to get them to work properly...

In any case, thanks for your help up until this point.

Cheers,
Bart.

 

[ChrisAG]

Do you have all speakers set to Small?

Is the receiver in an enclosed rack that may be inhibiting ventilation?

Since your Marantz is still under warranty, I wouldn't open it up... that will void it.

As for the Mordaunt-Short being too shrill, does the 5600 have a HT-EQ setting to reduce the high-frequencies of movies that are mixed too hot for the home? Check the manual for that, it may make a difference.

I'm curious, which Mordaunt-Short centre do you have?

 

[Bart_R]

Hey Chris,

Thanks for chipping in.

All speakers, except the two fronts (which are quite big), are set to small.

The receiver is standing on a little table with sufficient space around it (nothing on top of it either).

I just checked the manual for that EQ-feature, and apparently it does have such a thing. I will check out if that fixes my problem with the center. Still, it's probably not even noticeable (or a hindrance) for a third-person. I'm simply rather picky when it comes to these things. But I'll surely try out the HT-EQ function.

Oh and I have the MS 905c (center). Excellent lows, but also too pronounced highs for my liking. I'm glad to learn that the L-pad construction wasn't the problem of the PROTECT-mode kicking in, though.

Now all I need to do is find out how to let my two back surrounds participate properly...

Thanks for your useful comments and suggestions

 

[Bob McElfresh]

????

Does your receiver have outputs for these or did you 'fake' the second set of surrounds by simply running 2 sets of wires to your rear speaker terminals?

If you ran 2 sets of wires - this explains the problem.

Simply connecting up 2 speakers puts your rear speakers in PARALLEL. This makes the 2 speakers appear HALF the impedence. The more this happens, the closer you get to a direct short -> overheat.

Try this:

Run your speaker wire like a water pipe: Into 1 speaker, out, into the next speaker, out back to your receiver.

This puts the rear speakers in SERIES which will prevent the low-impedence from over-heating.

Then use a SPL meter to level adjust the rears and you should be fine.

 

[JeremyErwin]

Bob, The Marantz SR 5600 is a 7.1 receiver.

 

[Bart_R]

Bob, Jeremy has it right. I was talking about the back surrounds on my 7.1 receiver. Sorry for the confusion.

Anyway, I still have to determine how to let those two speakers function like all the others, without the receiver getting into standby mode, but I'm glad I at least know where the problem lies and that I can go into full blast mode (so to speak ) with 5.1 encoded material.