When to Add External Amplification to an A/V Receiver

[George H]

First time posting but long time user & fan of Audioholics which is a great reference tool. Gene & his team do a great job. I have a Pioneer SC-85 AVR running 5.2.4 atoms which has been running fine with no issues after 2 firmware updates.

The main problem is the amount of power provided by an external amp to Zone 2 which supports 4 pairs of 8 ohm speakers (PSB CS1000, PSB CS 500, BA Voyager 60 & BA Bravo). 2 external amps are connect to Zone 2 (Using Niles Amp cascade RCA connections to daisy chain the 2nd amp) External Amps Used: Niles SI-275 AMP (2 x 75 WPC@ 8 ohms), Emotiva XPA Gen3 -Two ( 2x 300 WPC @ 8 ohms);
Zone 2 has Multiple Outdoor Zones: Using a Dual Source, 4 Pair selector w/ volume control - Russound SDB 4.1.

Using a SPL meter I tested the db level of music playing at max level to the PSB CS1000 speakers (Zone 3) only using Emotiva XPA - 2 (Source A). All the other zones were off during this test to ensure all XPA power was directed to the active Zone 3 on the Russound. Results: SPL meter db avg. 80.0 , Peak 85.0.

I ran the same test again but connect the PSB CS 1000 speakers directly to Zone 2 terminals on the Pioneer SC-85 (135 WPC @8 ohms). Also, had to change the 5.2.4 AVR config in order to enable the Zone 2 terminals and used setup 5.1+Zone2+Zone3 for this test. Using SPL meter I tested the db level of music playing at max level to the PSB CS1000 speakers. Results: SPL Meter db Avg. 86.0 , Peak 95.0.

The SPL db meter differences between the 2 tests ranged between 5-10 db which can make big difference in overall performance.

Questions: Has anyone experienced these type of issues with db loss or power loss? Is the Russound SDB 4.1 a bottle neck? Is it normal or acceptable to expect this type of power loss with a heavy duty Russound switch?

I would appreciate and welcome any ideas, suggestions and recommendations that can help resolve this issue. After spending over $2000 for Emotiva XPA-2, Russound SDB, PSB Speakers and cabling I want to make sure it all works as expected......

Thanks.George

 

[George H]

First time posting but long time user & fan of Audioholics which is a great reference tool. Gene & his team do a great job. I have a Pioneer SC-85 AVR running 5.2.4 atoms which has been running fine with no issues after 2 firmware updates.

The main problem is the amount of power provided by an external amp to Zone 2 which supports 4 pairs of 8 ohm speakers (PSB CS1000, PSB CS 500, BA Voyager 60 & BA Bravo). 2 external amps are connect to Zone 2 (Using Niles Amp cascade RCA connections to daisy chain the 2nd amp) External Amps Used: Niles SI-275 AMP (2 x 75 WPC@ 8 ohms), Emotiva XPA Gen3 -Two ( 2x 300 WPC @ 8 ohms);
Zone 2 has Multiple Outdoor Zones: Using a Dual Source, 4 Pair selector w/ volume control - Russound SDB 4.1.

Using a SPL meter I tested the db level of music playing at max level to the PSB CS1000 speakers (Zone 3) only using Emotiva XPA - 2 (Source A). All the other zones were off during this test to ensure all XPA power was directed to the active Zone 3 on the Russound. Results: SPL meter db avg. 80.0 , Peak 85.0.

I ran the same test again but connect the PSB CS 1000 speakers directly to Zone 2 terminals on the Pioneer SC-85 (135 WPC @8 ohms). Also, had to change the 5.2.4 AVR config in order to enable the Zone 2 terminals and used setup 5.1+Zone2+Zone3 for this test. Using SPL meter I tested the db level of music playing at max level to the PSB CS1000 speakers. Results: SPL Meter db Avg. 86.0 , Peak 95.0.

The SPL db meter differences between the 2 tests ranged between 5-10 db which can make big difference in overall performance.

Questions: Has anyone experienced these type of issues with db loss or power loss? Is the Russound SDB 4.1 a bottle neck? Is it normal or acceptable to expect this type of power loss with a heavy duty Russound switch?

I would appreciate and welcome any ideas, suggestions and recommendations that can help resolve this issue. After spending over $2000 for Emotiva XPA-2, Russound SDB, PSB Speakers and cabling I want to make sure it all works as expected......

Thanks.George

 

[ski2xblack]

The Russound thingie does mention "impedance matching autoformers" so your suspicions about that piece imposing a bottleneck are probably on target. If you can arrange the signal routing to whichever zones upstream from that point it would be better, so that the amps couple directly to the speakers.

 

[GregBe]

Hey guys,

Great article Gene and discussion throughout. I haven't pulled out a scientific calculator (ever) so want to double check that I am figuring things out correctly.

The subwoofer output on my Pioneer VSX-94TXH just crapped out (drops in and out, but 90% of the time...no sound at all). Since I am about to pick up a 4K TV, figured it would be a good time to upgrade my receiver to the newest 4K video pass through. After reading the excellent review on the Denon 3300, and able to pick one up on closeout, I pulled the trigger. Seemed to hit a good price point for me to still be able to dump more money into my 4K tv. The Denon has less power than the Pioneer did so I want to make sure I didn't make the wrong choice because of amp power. I can always exchange it if it poses a probme..

My speakers Era Design 5 system is pretty innefficient - 85db 6ohm mains and 89.5db 4ohm center channel, I never had problems with the Pioneer at my listening levels at all. (pretty small room, 9' listening distance, below reference levels)

OK... here is my math. (Using measurements from Audioholics reviews of both receivers)

-Pioneer 155w with 2 channels driven, 8ohm, .1% THD
-Pioneer 270w with 1 channel driven, 4 ohm, .1% THD
-Denon 105w with 2 channels driven, 8 ohm, .1% THD
-Denon 163w with 1 channel driven, 4 ohm, .1% THD

So am I right that the Denon is only dropping by 1.69dB at 8ohm and 2.19dB at 4 ohms from what I was getting from my Pioneer? I am assuming this is pretty insignificant.

Any thoughts would be much appreciated!
Greg

 

[PENG]

Hey guys,

Great article Gene and discussion throughout. I haven't pulled out a scientific calculator (ever) so want to double check that I am figuring things out correctly.

The subwoofer output on my Pioneer VSX-94TXH just crapped out (drops in and out, but 90% of the time...no sound at all). Since I am about to pick up a 4K TV, figured it would be a good time to upgrade my receiver to the newest 4K video pass through. After reading the excellent review on the Denon 3300, and able to pick one up on closeout, I pulled the trigger. Seemed to hit a good price point for me to still be able to dump more money into my 4K tv. The Denon has less power than the Pioneer did so I want to make sure I didn't make the wrong choice because of amp power. I can always exchange it if it poses a probme..

My speakers Era Design 5 system is pretty innefficient - 85db 6ohm mains and 89.5db 4ohm center channel, I never had problems with the Pioneer at my listening levels at all. (pretty small room, 9' listening distance, below reference levels)

OK... here is my math. (Using measurements from Audioholics reviews of both receivers)

-Pioneer 155w with 2 channels driven, 8ohm, .1% THD
-Pioneer 270w with 1 channel driven, 4 ohm, .1% THD
-Denon 105w with 2 channels driven, 8 ohm, .1% THD
-Denon 163w with 1 channel driven, 4 ohm, .1% THD

So am I right that the Denon is only dropping by 1.69dB at 8ohm and 2.19dB at 4 ohms from what I was getting from my Pioneer? I am assuming this is pretty insignificant.

Any thoughts would be much appreciated!
Greg

You math is about right but it seems that you are mixing the Denon's numbers with the Yamaha so please double check and you will find that the Denon actually did better than you think.

Also, it is hard to compare the Denon with the Pioneer because Gene tested the Denon using CFP-BW on two channel driven only. For the Pioneer, it wasn't entirely clear but if we assume he also used CFP-BW for those figures, then you should be comparing as follow:

Pioneer VSX-94TXH

155W, 8 ohms, 225W 4 ohms.

Denon AVR-X3300W

105W, 8 ohms, 154W, 4 ohms.

So the difference for the 4 ohms test is about 1.63 dB. It is not significant, but to be on the safe side, I would add an external fan to blow from the back or the top of the AVR.

 

[GregBe]

Thanks PENG, That was really above and beyond. I really appreciate it!

Glad I erred in my favor. Wow...the 3300 really did test well.

Thanks again
Greg

Sent from my LG-H830 using Tapatalk

 

[Louis. L]

Hi Gene,

I am pretty new with home theater thing, but been watching a lot of your useful videos and learning some very good basic stuff. Thank you very much for your time doing this! I believe a lot of people like me would appreciate your work.
Today, with this topic, I'd like to have questions, please!
I have a Hi Fi 2 channel karaoke amplifier 2000 watts, 4 ohms (1000 watts/ ch).
I also have a pioneer elite vsx-21 txh 7.1 AV receiver 110 watts/ ch, 8 ohms.
With different watts and ohms like above, can I still connect my pioneer receiver to my karaoke amplifier because I just want the music to come out from all of the speakers I got. Also, what would happen if I connect these two amplifiers the other way around to watch movie because my blu-ray player is hooked up with my pioneer receiver.
Thank you very much
Hope to hear from you soon

Louis. L

 

[Louis. L]

And by the way, Gene,
Both receivers have pre-outs and line-ins.

Louis. L

 

[everettT]

Hi Gene,

I am pretty new with home theater thing, but been watching a lot of your useful videos and learning some very good basic stuff. Thank you very much for your time doing this! I believe a lot of people like me would appreciate your work.
Today, with this topic, I'd like to have questions, please!
I have a Hi Fi 2 channel karaoke amplifier 2000 watts, 4 ohms (1000 watts/ ch).
I also have a pioneer elite vsx-21 txh 7.1 AV receiver 110 watts/ ch, 8 ohms.
With different watts and ohms like above, can I still connect my pioneer receiver to my karaoke amplifier because I just want the music to come out from all of the speakers I got. Also, what would happen if I connect these two amplifiers the other way around to watch movie because my blu-ray player is hooked up with my pioneer receiver.
Thank you very much
Hope to hear from you soon

Louis. L

And by the way, Gene,
Both receivers have pre-outs and line-ins.

Louis. L

Can you explain the speaker setup? It's not clear what you wish to accomplish. If your feeding inputs to one or the other, Ohms will not be relevant since each amp would only be powering the speakers attached.

 

[Louis. L]

Can you explain the speaker setup? It's not clear what you wish to accomplish. If your feeding inputs to one or the other, Ohms will not be relevant since each amp would only be powering the speakers attached.

Thank you for replying so fast!
Ok, I will try my best to explain..., my current home theater is pioneer elite av receiver connecting with 7 speakers and one sub (100 watts/ ch). It sounds beautifully when watching movie or listening to music but not loud enough for Karaoke. Now, my sister just gave a new karaoke amplifier with 2 loud speakers (1000 watts each); so we tried to sing along in the family for fun, and it's loud, wonderfully loud. But, the sound comes out only from the 2 loud speakers, that's why I was just wondering if I can connect my current home theater system into my new karaoke amplifier, so the audio can be delivered from all 9 speakers. They are different in watts and ohm, I am not an audio pro, I really wouldn't want to blow up neither of them. Please, help!

Louis. L

 

[PENG]

Thank you for replying so fast!
Ok, I will try my best to explain..., my current home theater is pioneer elite av receiver connecting with 7 speakers and one sub (100 watts/ ch). It sounds beautifully when watching movie or listening to music but not loud enough for Karaoke. Now, my sister just gave a new karaoke amplifier with 2 loud speakers (1000 watts each); so we tried to sing along in the family for fun, and it's loud, wonderfully loud. But, the sound comes out only from the 2 loud speakers, that's why I was just wondering if I can connect my current home theater system into my new karaoke amplifier, so the audio can be delivered from all 9 speakers. They are different in watts and ohm, I am not an audio pro, I really wouldn't want to blow up neither of them. Please, help!

Louis. L

You should be able to simply feed the same signal to the Karaoke amp and the Pioneer Elite. If you do that you shouldn't blow anything up because you will be keeping the two systems separate If you want to feed the signal into the Elite and then use preouts to drive the Karaoke amp then we probably should know more about your Karaoke amp. The model number alone may be enough as we can then search for the instruction manual.

 

[Louis. L]

You should be able to simply feed the same signal to the Karaoke amp and the Pioneer Elite. If you do that you shouldn't blow anything up because you will be keeping the two systems separate If you want to feed the signal into the Elite and then use preouts to drive the Karaoke amp then we probably should know more about your Karaoke amp. The model number alone may be enough as we can then search for the instruction manual.

Thank you Boss, I really appreciate for your help!
the model of the karaoke amp is:
Pyle PMXAKB2000 - 2000 Watt DJ Karaoke Mixer and Amplifier with Built-in Bluetooth

Thank you

Louis. L

 

[mtrot]

I added a power amp to my Denon AVR-X5200W primarily in an attempt to give my speakers a "kick in the bass", if you will. The amp is a massive class A Krell FPB 400cx, which is rated 400 watts per channel into 8 ohms. Perhaps it was an ill-advised expense. I'm not sure that it resulted in a quantum leap in bass performance, but I do actually think it has improved the overall sound. I feel that the sound stage, imaging, and timbre of instruments and vocals are better with the Krell. Anyway, I really like the sound I now get, so I'm happy with it.

 

[Louis. L]

Thank you for your help>

Louis. L

 

[PENG]

Thank you Boss, I really appreciate for your help!
the model of the karaoke amp is:
Pyle PMXAKB2000 - 2000 Watt DJ Karaoke Mixer and Amplifier with Built-in Bluetooth

Thank you

Louis. L

The only downloadable manual I could find was not very legible. Still, I believe it has RCA audio inputs only but no RCA audio outputs. So probably the easiest way for you to have both making sound is to do it like before you acquired the Pyle, but now you can connect the Pioneer's RCA audio output to one of the RCA audio inputs on the Pyle amp. How did you use the Pioneer for Karaoke though, did you use another mixer?

The choices of outputs from the Pioneer could be the Zone 2, 3, or tape out. If that doesn't work out then you may try the Pre outs for the front channels. Otherwise, as I mentioned before, you may figure out a way to feed the same source signal (DVD/CD players etc.) to both the Pioneer and the Pyle, but obviously the voice would then be mixed in through the Pyle only.

 

[Jayson Berlin]

I have few questions, similar to this topic. I just bought Onkyo TX-NR575/ AV receiver, and only have 5 channels of 7, inside wired, and also the has Zone 2, 2 kicker KB 6000 for outside on patio. And when I at Zone 2 at 75+ Volume, the receiver heats up and shuts down. Says to check speaker wire. And now support with Onkyo, says they inly fix is Pre-amp, is that true and if so, what's by best option. Thanks

 

[M Code]

The subject Pyle PMXAKB2000 Karoke amplifier claiming to be 2KW (1KW x 2) sells for $189..
Total BS....
More than likely a real power output rating is 50W or 25W x 2...

Just my $0.02...

 

[Verdinut]

The subject Pyle PMXAKB2000 Karoke amplifier claiming to be 2KW (1KW x 2) sells for $189..
Total BS....
More than likely a real power output rating is 50W or 25W x 2...

Just my $0.02...

And probably not even clean!

 

[hk2000]

What I want to know is this: Can an amp power output decrease with age? I use Onkyo/Carver per-amp/power amp combo, and recently I've been having to turn the volume way up to reach levels it used to easily get to.

 

[Verdinut]

In the case of a solid state amplifier, it's output power should not decrease with time. However, your hearing acuity will decrease with time and you will have to adjust the volume then.

In your case, having to turn the volume way up, there seems to be a problem with your equipment as the situation is not normal. For starters, I suggest that you verify or change the interconnects between the preamp and the power amp and see if this procedure works.