Onkyo AVR875 ---reasons for the 875 to go into protection mode??

subhash

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hi ,i have noticed this problem ie ; my onkyo 875 has recently started to go into protection mode ,(switches off for a few secs ) offcourse @ very high volumes , but i guess it shud not happen, what cud the reasons be ??

my set up is 7.1, the avr is connected to pioneer BDP via HDMI
onkyo 875 is purely acting as a pre/processor
---mains Jamo C809 are driven by the new VIncent SP331MK power amp thro the preouts of the avr
---centre /sorrounds driven by the carver power amp
---the onkyo does drive the 2 back sorrounds
---velodyne sub is connected to the AVR

the settings on the avr
the l/r mains 4 db
centre odb
l/r sorrounds @ 8db
back sorrounds @4db
sub -3 db
i have not done the audessy sound calibrations
i have already chkd for any loose spkr wires @ the rear of the AVR, there are none as its all thro banana plugs

one more thing i want to mention is i have noticed this problem only with bluray play back @ volume levels of -4 (the vol control starts @-60 and goes upto -0 and upto +4 db) that means @ abt 70:/: of the volume

any suggestions /advice will be of great help
 
After going through your problem I think that its your vincent power amp which is causing your AVR to trip at higher volumes. This is due to the fact that Onkyo's Pre outs gives only 1V output whereas your Vincent Demands 1.5 -2 V at the pre out level which causes this tripping at higher volumes.
 
After going through your problem I think that its your vincent power amp which is causing your AVR to trip at higher volumes. This is due to the fact that Onkyo's Pre outs gives only 1V output whereas your Vincent Demands 1.5 -2 V at the pre out level which causes this tripping at higher volumes.

Ashish: You have a point here. However, I always thought that the protection circuit was triggered by on-board power amplifier circuit. Comment..
 
Ashish: You have a point here. However, I always thought that the protection circuit was triggered by on-board power amplifier circuit. Comment..

A power amplifier need required amount of current through pre outs to perform at its optimum level and in Subhash's Case it proves with the fact that he has set his front channel level at +4 in the pre amp i.e 875 here to fulfill the demands of the power amp but in trying to do so its also made to work hard by the power amp here which results in the tripping at higher volume levels. This is a classic case of mismatch of pre and power combination.
 
thanks ashish, i spoke to sreedhar/odyssey yday after speaking to you , after telling him about the issue ,he told me it may not be the 1volt and 1.5-2 volts difference of the AVR / power amp

he adviced me to disconnect the back sorrounds ,which is powered by the 875, in 7.1 mode and chk out at the same vol levels
he also reffered to the vol levels (70:/: ) was a bit too much for the onkyo AVR to handle----will try out
also ashish adviced to power my main spkrs directly via the AVR and chk with the same vol levels

AS i love action/sfx movies to be driven @ extreme vol levels i wud like to know what are the options i have here


any opinion /advice will be appreciated
 
Ashish: So, you are trying to say that the protection trigger is also in the pre-amp circuit?

Subhash:This happens during Blu ray playback because there is greater amount of data being transferred i.e. HD audio which is clearer and louder for same volume level compared to DVD playback.

Still, Subhash your problem remains unresloved. I have a some what similar config compare to your albeit I have an extra pre in between.

AVR + NAD Pre + NAD Power.

Experts might say that it does not make sense to send the signal through two pre-amps. Theoretically, they may be right. Practically, the system works flawlessly. But, I still have not tested this on blu ray as I don't own one!!!

If you are unable to find a solution to this problem then may I suggest you borrow a matching pre-amp and connect the same in between AVR and Power amp. In this case you can enjoy pure audiophile 2 channel sound and keep you AVR in 'off' position when listening to 2 ch audio. You CD player ? tape deck and other 2 channel sources can be directly connected to the pre.

I am not sure if Sridhar is right about Onkyo not being able to handle 70% of the volume. 875 is a top end amp. It can handle more than that. furthermore, in your case 875 power amp section isn't doing much anyways.

I think Ashish point is stronger here. But, still I am not sure.

have you tried speaking to Onkyo?

Sumit
 
this issue was first noticed when watching King kong on BLU ray on DTS HD MA, this happened towards the end of the movie when the empire building is under fire from the war planes , to recheck i played the same chapter again @ same levels it happened again

interesting fact -it doesnt go into protection mode @ a slightly higher vol levels (-2) when playing the same movie/chapter via DVD playback!!

also i did chk the heat of the AVR it was normal and did not feel like it was over heated (AC was in full )
 
Ashish: So, you are trying to say that the protection trigger is also in the pre-amp circuit?

Subhash:This happens during Blu ray playback because there is greater amount of data being transferred i.e. HD audio which is clearer and louder for same volume level compared to DVD playback.

Still, Subhash your problem remains unresloved. I have a some what similar config compare to your albeit I have an extra pre in between.

AVR + NAD Pre + NAD Power.

Experts might say that it does not make sense to send the signal through two pre-amps. Theoretically, they may be right. Practically, the system works flawlessly. But, I still have not tested this on blu ray as I don't own one!!!

If you are unable to find a solution to this problem then may I suggest you borrow a matching pre-amp and connect the same in between AVR and Power amp. In this case you can enjoy pure audiophile 2 channel sound and keep you AVR in 'off' position when listening to 2 ch audio. You CD player ? tape deck and other 2 channel sources can be directly connected to the pre.

I am not sure if Sridhar is right about Onkyo not being able to handle 70% of the volume. 875 is a top end amp. It can handle more than that. furthermore, in your case 875 power amp section isn't doing much anyways.

I think Ashish point is stronger here. But, still I am not sure.

have you tried speaking to Onkyo?

Sumit

hi sumit , i do have a matching pre amp for the vincent power amp SP331mk, its the SA31MK pre amp for the power, but i use this strictly for music ,all i do is unplug the inputs from the AVR to the power amp and connect the preamp out to it ( as i have kept seperate inter connects @ the back)

if u connect an extra pre ,dont u think it alters the sound quality, as there are 2 pre amps working simultaneously here, u may get exagerated highs and lows(which cud sound unnatural) whats your setting in the AVR and the nad pre
 
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hi sumit , i do have a matching pre amp for the vincent power amp SP331mk, its the SA31MK pre amp for the power, but i use this strictly for music ,all i do is unplug the inputs from the AVR to the power amp and connect the preamp out to it ( as i have kept seperate inter connects @ the back)

if u connect an extra pre ,dont u think it alters the sound quality, as there are 2 pre amps working simultaneously here, u may get exagerated highs and lows(which cud sound unnatural) whats your setting in the AVR and the nad pre

Subhash, I have used a SPL meter to calibrate my system. I have kept the NAD pre volume knob to 12'O position and then I have calibrated the complete system. I have not experienced anything unnatural or maybe I don't have golden ears. Point is that I am satisfied.

Plus changing IC everytime when switching from movies to music is not a good idea. Subhash, you have all the goods. Why don't you just try.

Lets go over the Connections once again:

Connect your speakers to respective power amps except rear surrounds which are connected to AVR.
Connect BDP and DVDP to AVR vide HDMI.
Connect CD player/DAC/2 Channel source directly to Vincent Pre.

Connect AVR LR pre-out to Vincent Pre. Connect it to AUX jack- just easier to remember.
Now Connect Vincent Pre to Vincent power.

Now, you actually need a SPL meter to get things right in the first place. This is must. Becuase, you have to keep the Vincent preamps's volume knob to 12'Oclock position. See if you can arrange one from nearby.

Working:

When you are listening to music only, Vincent pre-power and source is required only. When you are watching a movie, the complete equipment needs to be turned 'on'. Set the Vincent pre volume to 12'O clock position and select source as AUX. Now, control the volume of the complete system from the AVR remote. Done.

Subhash, you have the goods. All you need is an extra IC and a SPL meter to calibrate your system. Even if you don't have an SPL meter, still you can atleast test the new config with approximation.

Cheers!!
 
Subhash and I discussed this over phone yesterday and he was really concerned. Subhash watches movies at very high volumes and his AVR is running for protection:D.

On a serious note, could the problem be that his Onkyo AVR is getting over-loaded for just the section powering the two rear surrounds (in bold below).

my set up is 7.1, the avr is connected to pioneer BDP via HDMI
onkyo 875 is purely acting as a pre/processor
---mains Jamo C809 are driven by the new VIncent SP331MK power amp thro the preouts of the avr
---centre /sorrounds driven by the carver power amp
---the onkyo does drive the 2 back sorrounds---velodyne sub is connected to the AVR

Also Ashish, could you please share some details about possible effects of voltage mismatch? I would like to understand this as I am about to attempt below suggestion by Sumit.

Lets go over the Connections once again:

Connect your speakers to respective power amps except rear surrounds which are connected to AVR.
Connect BDP and DVDP to AVR vide HDMI.
Connect CD player/DAC/2 Channel source directly to Vincent Pre.

Connect AVR LR pre-out to Vincent Pre. Connect it to AUX jack- just easier to remember.
Now Connect Vincent Pre to Vincent power.

Now, you actually need a SPL meter to get things right in the first place. This is must. Becuase, you have to keep the Vincent preamps's volume knob to 12'Oclock position. See if you can arrange one from nearby.

Working:

When you are listening to music only, Vincent pre-power and source is required only. When you are watching a movie, the complete equipment needs to be turned 'on'. Set the Vincent pre volume to 12'O clock position and select source as AUX. Now, control the volume of the complete system from the AVR remote. Done.

Thanks Sumit for putting those steps in detail. You had suggested same/similar solution on my HT thread because I had two sets of front speakers - one for movies and the other for stereo. I shall try this out over the weekend.
 
Well tyring default setting like fronts '0' ,centre '-2' can solve the problem.
Auddecy sets fronts as -4 or lower,so setting preamp vol less may solve pro @ higher volumes.
 
On a serious note, could the problem be that his Onkyo AVR is getting over-loaded for just the section powering the two rear surrounds (in bold below).



It could be reason if the levels are set too high for the surround channels to take the load off.


Also Ashish, could you please share some details about possible effects of voltage mismatch? I would like to understand this as I am about to attempt below suggestion by Sumit.


Santosh think of it like running an AC through a generator in which as soon as the compressor starts it wants more current from the generator which if already running on overload i.e giving more than its capacity through tweaking with its alternator might burn or fail altogether. So in Subhash's case too the Onkyo is rated at maximum voltage of 1 volt at the pre out level which I have already mentioned but the vincent amp requires minimum of 1.5 to 2 volt at the startup and to fill up this Gap Subhash will have to bump up the channel volume settings in his Onkyo. When they work in sync they exchange the voltage between the two gears and sometimes when the demand exceeds at the peak levels the required amount of current is out the capability of Onkyo which would go into protection at that stage.
 
Subhash, I have used a SPL meter to calibrate my system. I have kept the NAD pre volume knob to 12'O position and then I have calibrated the complete system. I have not experienced anything unnatural or maybe I don't have golden ears. Point is that I am satisfied.

Plus changing IC everytime when switching from movies to music is not a good idea. Subhash, you have all the goods. Why don't you just try.

Lets go over the Connections once again:

Connect your speakers to respective power amps except rear surrounds which are connected to AVR.
Connect BDP and DVDP to AVR vide HDMI.
Connect CD player/DAC/2 Channel source directly to Vincent Pre.

Connect AVR LR pre-out to Vincent Pre. Connect it to AUX jack- just easier to remember.
Now Connect Vincent Pre to Vincent power.

Now, you actually need a SPL meter to get things right in the first place. This is must. Becuase, you have to keep the Vincent preamps's volume knob to 12'Oclock position. See if you can arrange one from nearby.

Working:

When you are listening to music only, Vincent pre-power and source is required only. When you are watching a movie, the complete equipment needs to be turned 'on'. Set the Vincent pre volume to 12'O clock position and select source as AUX. Now, control the volume of the complete system from the AVR remote. Done.

Subhash, you have the goods. All you need is an extra IC and a SPL meter to calibrate your system. Even if you don't have an SPL meter, still you can atleast test the new config with approximation.

Cheers!!

will definetly give it a try

one more ?? what abt the tone controls
1--tone controls in the pre amp shud be used or by passed
2--levels of tone control in the AVR settings
 
Well tyring default setting like fronts '0' ,centre '-2' can solve the problem.
Auddecy sets fronts as -4 or lower,so setting preamp vol less may solve pro @ higher volumes.

will try and give u a feed back, but according to ashish this may not work
and also as all the chanells are driven by external power amps , i guess there is less load on the AVR and so it shud not get into protection mode
 
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one more point i wish to say is when the AVR went into protection mode ,it was playing in 5.i dts hd ma , although the back sorrounds were only connected , but the setting was 5.1

so the amp sec getting overheated by driving only the 2 bak sorrouds may not hold good
 
one more point i wish to say is when the AVR went into protection mode ,it was playing in 5.i dts hd ma , although the back sorrounds were only connected , but the setting was 5.1

so the amp sec getting overheated by driving only the 2 bak sorrouds may not hold good

Saying that ,you connected frontd to external amp & surr with inbuilt amp(875)In this case your frnt internal amp may get into action without output to spk.This cld be the cause too.
 
will definetly give it a try

one more ?? what abt the tone controls
1--tone controls in the pre amp shud be used or by passed
2--levels of tone control in the AVR settings

1- I have kept the tone controls 'on' and level '0' for both base and treble.
2- Keep the tone controls flat for AVR. Adjust these only of you feel you need to. There is no harm in doing so.

Spiro: How can the internal amp get into action when there is no power drawn from it? Yes, the internal amp could be ready but thats it. There will be no load on the amp and hence it can contribute to clipping! Please explain.
 
Saying that ,you connected frontd to external amp & surr with inbuilt amp(875)In this case your frnt internal amp may get into action without output to spk.This cld be the cause too.

sorry cudnt get the point here , the l/r sorrounds are also powered by an external power amp ( carver tfm 35x) same with the centre too which is powered by another tfm 35x in mono mode

only the back sorrounds are powered by the AVR
 
sorry cudnt get the point here , the l/r sorrounds are also powered by an external power amp ( carver tfm 35x) same with the centre too which is powered by another tfm 35x in mono mode

only the back sorrounds are powered by the AVR

My guess- You have powered surr back with AVR & rest with external.
So @ high vol,chances are that surr back spk get over powered as all AVR power is directed to surr back.So may AVR trip.
 
My guess- You have powered surr back with AVR & rest with external.
So @ high vol,chances are that surr back spk get over powered as all AVR power is directed to surr back.So may AVR trip.

will disconnect the back sorrounds from the AVR and chk today
 
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