Denon - Amp disconnect

[DJ7675]

I read the review about the X3600 amp disconnect feature, allowing up to 4V unclipped. I have the X8500, if I set the amp to "none" in the custom amp assignment menu, does that do the same thing? Why I ask is I am using active speakers for my L/C/R and could use the 4V. Is this correct?

 

[WaynePflughaupt]

What active speakers are you using? I’ve never seen even the most powerful of professional amps that required a 4V input signal. I highly doubt that your speakers do.

Regards,
Wayne A. Pflughaupt

 

[DJ7675]

What active speakers are you using? I’ve never seen even the most powerful of professional amps that required a 4V input signal. I highly doubt that your speakers do.

Regards,
Wayne A. Pflughaupt

JBL 705P on the balanced inputs

 

[WaynePflughaupt]

There’s no reason to use the JBL’s balanced inputs since the Denon has no balanced outputs.

Just set the JBL for-10 dB input sensitivity. It should work just fine. However, if you get clipping issues, then change the input sensitivity to +4 dB.

If you want a rough idea of what the Denon’s output voltage, see Part 7 of my gain structure article, which you can find in my signature.

Regards,
Wayne A. Pflughaupt

 

[lovinthehd]

There’s no reason to use the JBL’s balanced inputs since the Denon has no balanced outputs.

Just set the JBL for-10 dB input sensitivity. It should work just fine. However, if you get clipping issues, then change the input sensitivity to +4 dB.

If you want a rough idea of what the Denon’s output voltage, see Part 7 of my gain structure article, which you can find in my signature.

Regards,
Wayne A. Pflughaupt

There's some other input to use? Looks like he needs an rca to xlr cable....tho I agree the -10dB setting would be the one to use.

 

[DJ7675]

Thanks Wayne, will check out your article. I always enjoy learning something. And yes, I have an rca>xlr cable from the x8500.

 

[WaynePflughaupt]

Most pro devices these days use XLR “combi” female jacks that can accept a 1/4” input in the center. I can’t determine from on-line pictures or the manual if the 705 has this feature, or merely standard female XLRs. Regardless, no reason to change cables as the RCA-XLR will work fine.

Regards,
Wayne A. Pflughaupt

 

[lovinthehd]

Most pro devices these days use XLR “combi” female jacks that can accept a 1/4” input in the center. I can’t determine from on-line pictures or the manual if the 705 has this feature, or merely standard female XLRs. Regardless, no reason to change cables as the RCA-XLR will work fine.

Regards,
Wayne A. Pflughaupt

The manual just seems to indicate AES/analog XLR inputs....

 

[PENG]

I read the review about the X3600 amp disconnect feature, allowing up to 4V unclipped. I have the X8500, if I set the amp to "none" in the custom amp assignment menu, does that do the same thing?

I am not sure what you meant by "....set the amp to "none".........." Did you mean settings in the speaker configuration manual, if not, where? A screen shot of that setting page would be great.

From what I understand the feature you referred to only apply the the X3600H, X4400/4500H (may be 4300 too) and the corresponding Marantz models such as the SR6012/6013/6014/7012 through 7013 (may be the 6011/7011 also.

I believe that "feature" is most likely an unintended feature discovered by Gene. It came from the fact that those receivers can process 11.1 channels but has only 9 internal amps, such they came up with the "assign" feature that allows you to assign two of the amps to the "height", zones, or combinations of both and in doing so it has to free up two pre outs for connection to an external two channel amp.

The X6400H and X8500H won't have such unintended feature because they have enough internal power amps to power all the channels that they are designed to do, that is the maximum channels to be powered = the maximum channels they can processed.

At least the X8500H has the preamp mode, the X6400/6500H has not. For that reason, I actually prefer the X4400/4500H.

 

[DJ7675]

Thanks for your reply PENG. On the X8500 menu this is where I am at:
Setup>speakers>manual setup>amp assign>set to custom
Then at the bottom left are “Settings”
As show in the picture, I have set the F/R and Center to none. In the description for this option on the Denon it says “Selects the signal output from the front speaker terminals”
My assumption would be setting them to “none” would disconnect the amp (like it would in preamplifier mode”.
Also note, just like the x3600 the X8500 Can reassign the F/L amp to zone2/zone3. So if reassigned, I would think it would act like the X3600. If the amp is being used elsewhere, it must be disconnected.
If setting the amp for the F/L/C to none turns off the speaker terminals for those channels it seems logical to me that the amp is disconnected when set to none.

 

[PENG]

Thanks for your reply PENG. On the X8500 menu this is where I am at:
Setup>speakers>manual setup>amp assign>set to custom
Then at the bottom left are “Settings”
As show in the picture, I have set the F/R and Center to none. In the description for this option on the Denon it says “Selects the signal output from the front speaker terminals”
My assumption would be setting them to “none” would disconnect the amp (like it would in preamplifier mode”.
Also note, just like the x3600 the X8500 Can reassign the F/L amp to zone2/zone3. So if reassigned, I would think it would act like the X3600. If the amp is being used elsewhere, it must be disconnected.
If setting the amp for the F/L/C to none turns off the speaker terminals for those channels it seems logical to me that the amp is disconnected when set to none.
View attachment 34360

It will be great if it can work the way you described. It is easy to try and find out for sure. Please let us know the result.

 

[DJ7675]

I know the x8500 has a preamp mode where it disconnects all amps. It would make sense that you could do it channel by channel. Right now I am using it this way with JBL 308 MKii's soon to be replaced with 305P's. How is it easy to find out for sure? Check the speaker outs?

 

[PENG]

I know the x8500 has a preamp mode where it disconnects all amps. It would make sense that you could do it channel by channel. Right now I am using it this way with JBL 308 MKii's soon to be replaced with 305P's. How is it easy to find out for sure? Check the speaker outs?

If you are already using it "this way", and your jbls are powered by the front pre outs, then you can try connecting a speaker to the front speaker out, doesn't matter FL, FR, or both. If the speakers don't make any sound then you got it right..

Or you can measure the FR/FL speaker out binding posts with a voltmeter.

 

[DJ7675]

Will do.

 

[DJ7675]

I think I have an answer. Under amp settings if you set them to None there is no output on the speaker terminals. To test, I hooked up a speaker to the speaker output, on the front right speaker after setting the amp to "none" in the custom amp assign menu on the main speakers. Then I went to the speaker levels setup and on there was no output to the speaker I temporarily hooked up to the front right output. It would seem to me this means that the amp is disconnected when set to none. It would seem that this would be the same as setting the unit to preamplifier mode, which would disconnect all speakers. For those with some active speakers, this mode could be helpful it would seem as it could output higher levels with less noise/distortion that if the internal amps are connected. It would be interesting to see how the 8500 performs as a preamp only when set to none (on individual channels) or if the 8500 is set to preamp mode globally disconnecting all amps when compared to the Marantz 7705/8805. I was really hoping there would be a complete review/bench test of the 8500 but unfortunately somehow the x8500 has really escaped without a complete bench test here, hometheaterhifi, and sound and vision. I hope to be able to send my x8500 in to audiosciencereview to see how it compares later this spring.

 

[PENG]

I think I have an answer. Under amp settings if you set them to None there is no output on the speaker terminals. To test, I hooked up a speaker to the speaker output, on the front right speaker after setting the amp to "none" in the custom amp assign menu on the main speakers. Then I went to the speaker levels setup and on there was no output to the speaker I temporarily hooked up to the front right output. It would seem to me this means that the amp is disconnected when set to none. It would seem that this would be the same as setting the unit to preamplifier mode, which would disconnect all speakers. For those with some active speakers, this mode could be helpful it would seem as it could output higher levels with less noise/distortion that if the internal amps are connected. It would be interesting to see how the 8500 performs as a preamp only when set to none (on individual channels) or if the 8500 is set to preamp mode globally disconnecting all amps when compared to the Marantz 7705/8805. I was really hoping there would be a complete review/bench test of the 8500 but unfortunately somehow the x8500 has really escaped without a complete bench test here, hometheaterhifi, and sound and vision. I hope to be able to send my x8500 in to audiosciencereview to see how it compares later this spring.

Congratulations! You have found this undocumented (I read the owner's manual, nothing about assigning FL/FR to "none, and perhaps unintended feature. I agree based on your findings, that the 8500 can disconnect just about any amp channels yet still have the pre out functioning for the channels where the default power amp(s) is/are disconnected. This is in addition to the normal/intended preamp mode, that disconnects all 13 power amps.

I would bet when the power amps are disconnected, it would measure about the same as the Marantz AV8805, may even have lower THD+N at slightly lower output level because it does not have the extra HDMI buffer. That's of course just my guess and we may never know unless Amir got his hand on one to measure.

 

[DJ7675]

Congratulations! You have found this undocumented (I read the owner's manual, nothing about assigning FL/FR to "none, and perhaps unintended feature. I agree based on your findings, that the 8500 can disconnect just about any amp channels yet still have the pre out functioning for the channels where the default power amp(s) is/are disconnected. This is in addition to the normal/intended preamp mode, that disconnects all 13 power amps.

I would bet when the power amps are disconnected, it would measure about the same as the Marantz AV8805, may even have lower THD+N at slightly lower output level because it does not have the extra HDMI buffer. That's of course just my guess and we may never know unless Amir got his hand on one to measure.

Thanks for your reply. The thing about the 8500 is that every single channel the amps can be set to none if you want. So those that have a mix of active and passive speakers could use this to get better performance on those active speakers, or on channels that you want external amplification.

 

[PENG]

Thanks for your reply. The thing about the 8500 is that every single channel the amps can be set to none if you want. So those that have a mix of active and passive speakers could use this to get better performance on those active speakers, or on channels that you want external amplification.

Keep in mind in your case this feature may not make any difference depending on the sensitivity of your active speakers as the X8500H would clip at much higher output than the X3600H, or even the X4500H. Even the pre out of the X3300H, X3500H measured very well at lower output, and only got "grainy" when the power amp output clipped (yes, even with no speakers connected).

 

[DJ7675]

Keep in mind in your case this feature may not make any difference depending on the sensitivity of your active speakers as the X8500H would clip at much higher output than the X3600H, or even the X4500H. Even the pre out of the X3300H, X3500H measured very well at lower output, and only got "grainy" when the power amp output clipped (yes, even with no speakers connected).

Thanks and understood. I know Gene here at Audioholics has been lobbying for this amp disconnect, or preamp mode on receivers for some time (rightly so), but it seems that the X8500 does just that, either all channels (set in system wide for all channels preamp mode) or on a channel by channel basis in their custom amp asign mode. In some ways, it seems to make the x8500 a bit of a bargain since you can choose to use all of the amps, some of the amps, or no amps and disconnect the amps you want to use (or repurpose them to other rooms). It will be interesting to see how it performs relative to the 7705 and 8805 since Amir has already tested those.