Pioneer VSX-LX505 AVR Review

[respice finem]

Depends on how they implemented it I guess! - and whether the kerfuffle on ASR with regards to the Pio/Onkyo/Integra nanny circuits, is sufficient to cause marketing concerns for the company... which I doubt. - there are no reported instances of this happening in the "real world" (ie away from a lab measurement bench test).

OK, but still, not meeting the stated power figures isn't helping brand reputation. Even if it's not a problem for most, as it seems.
Looking at AVR tests in general, if I were to buy today, I would rather get an AV preamp, preferably with XLR outputs, and care for amplification myself.

 

[dlaloum]

OK, but still, not meeting the stated power figures isn't helping brand reputation. Even if it's not a problem for most, as it seems.
Looking at AVR tests in general, if I were to buy today, I would rather get an AV preamp, preferably with XLR outputs, and care for amplification myself.

I believe that they do meet their stated power figures!

The quoted specs are:
230 W/ch 6 ohms, 1 kHz, THD 10 %, 1ch Driven
120 W/ch 8 ohms, 20 Hz-20 kHz, THD 0.08 %, 2ch Driven FTC

No quoted 4ohm specs... the 1 ch driven 6 ohm spec doesn't specify a method that has a time component

I have the baby version (Integra DRX3.4) which is only 100W rated into 8ohm - but knowing it is current constrained and not suited to low impedance speakers (which my mains are) - I run it with external amps.

 

[HerbertThePervert]

I use a sc LX 701 as a preamp, for that it is fine.

Furthermore it has auto adjustment for delayed LFE channels (yes that is an issue on quite some releases). Only the high end Denons offer that aswell.

 

[respice finem]

I believe that they do meet their stated power figures!

The quoted specs are:
230 W/ch 6 ohms, 1 kHz, THD 10 %, 1ch Driven
120 W/ch 8 ohms, 20 Hz-20 kHz, THD 0.08 %, 2ch Driven FTC

But then, it should deliver more power, not less, into 4 ohms?

 

[dlaloum]

But then, it should deliver more power, not less, into 4 ohms?

All being equal, and assuming it has the current capacity in the power supply, and the load handling in the output circuits....

 

[dlaloum]

I use a sc LX 701 as a preamp, for that it is fine.

Furthermore it has auto adjustment for delayed LFE channels (yes that is an issue on quite some releases). Only the high end Denons offer that aswell.

The 701 is a class D power amp, where the 505 is a class AB - they are very different beasts, and would behave quite differently I would assume...

 

[DavidMcRoy]

But then, it should deliver more power, not less, into 4 ohms?

What's the "load" with no speakers connected? My similar VSX-LX503 (not a 505) shuts down on moderate pink noise levels after several minutes when just used as a pre-pro. There appears to be a circuit that samples the amount of time a signal with very consistent level is present, such as when the unit is being operated under "test conditions." There might even be multiple conditions that when met together will suffice to trip the circuit, but perhaps not unless a certain combination of conditions are met. Who knows?

 

[JayGilb]

Depends on how they implemented it I guess! - and whether the kerfuffle on ASR with regards to the Pio/Onkyo/Integra nanny circuits, is sufficient to cause marketing concerns for the company... which I doubt. - there are no reported instances of this happening in the "real world" (ie away from a lab measurement bench test).

Exactly - I guessing this has impacted very few users and by most accounts they find the performance of this unit perfectly fine.

 

[abdo123]

you can do the sums!

You will be trigering the protection when listening at distances larger than 4 meters if you want reference levels.

Which is nothing for enthusiast spaces.

 

[TonyJZX]

i would imagine these guys did their sums and if you have a big subwoofer, and you would if you own this... maybe they never expected more than 35 secs of peak power...

 

[beaRA]

Does anybody know the loudest 35 seconds in cinema so we can see if we can trip the nanny circuit with any real content?

 

[beagleman]

You will be trigering the protection when listening at distances larger than 4 meters if you want reference levels.

Which is nothing for enthusiast spaces.

I can not imagine any signal staying at that high wattage "Continuously" though. Sure, easily bouncing above and below that level at times, but we are talking with a 4 ohm load 20-20khz unwavering sine waves for 35 seconds to for sure trigger it.

Music and movie action are never this loud without variation in the signal.

What does bandwidth limiting do to this "feature"....will an 80Hz high pass still set it off??

 

[abdo123]

I can not imagine any signal staying at that high wattage "Continuously" though. Sure, easily bouncing above and below that level at times, but we are talking with a 5 ohm load 20-20khz unwavering sine waves for 35 seconds.

Music and movie action are never this loud without variation in the signal.

you really can't think of anything that would go over -20dbfs for 35 seconds continuously in a movie? like even the sound track goes above that.

 

[Dj7675]

This is a hard one... seems like a very good option for use as a processor. But it is a home theater receiver, with amps. Similar the Onkyo, to have it go into a low power mode that requires a reboot (without any sort of warning or status) is just not appropriate behavior. As soon as (or if) Pioneer/Onkyo/Integra release one that has DLBC and/or the new ART (Dirac Active Room Treatment) it would make an excellent processor.

 

[Dmitri]

What is the standard?…or is there any? X rated power for x amount of time prior to protection circuit/limiter engaging?
Whether or not it’s an issue in the real world is one thing. The reboot requirement is ridiculous.

 

[Rottmannash]

Apparently this is the amp PCB. Output transistors crammed onto a cheap heatsink...
View attachment 255503

so the huge heatsink on the front is for? Video processing?

 

[iraweiss]

How old of a monitor would you need to have to still use composite video? At last twenty years old? More?

Those are video inputs, not outputs, for people who own a VCR, LaserDisc (LD) player, or really old pre-HDMI DVD players. FWIW I have a Pioneer LD player myself.

 

[beagleman]

you really can't think of anything that would go over -20dbfs for 35 seconds continuously in a movie? like even the sound track goes above that.

For 35 seconds...?? A jet airplane takeoff at very high volume?
Sound and music and action and stuff alternate up and down, even within the mostly loud parts.
They are not continuous sounds that do not vary.


My daughter just had on some REALLY loud movie, with a part that was annoyingly loud action. As loud and annoying as I thought it was, it was literally only about 9-10 seconds of very loud, even thought it sounded like a full minute....

 

[RichT]

Thanks Amir for the review, I have the LX-305 and have had a lot of fun with it. The Dirac live feature is transformative. So far every AVR reviewed is disappointing in some way. Good luck finding an AVR that has stellar performance

 

[JDS]

This is a review and detailed measurements of the Pioneer VSX-LX505 ELITE 9.2 Channel AV Receiver. It was kindly drop shipped to me by a member and is a refurbished unit. Normal cost is US $1699.
View attachment 255469

As you see, the front panel is the same old interface from decade+ back. The on-screen menus though were speedy so perhaps the engine underneath is more modern. Back panel is also a sign of things long past with component and composite video inputs:

View attachment 255470

I forced a factory reset (came that way anyway) and check for firmware updates. None were available so I trust it is up to date

Attractiveness of this unit is due to availability of Dirac Room EQ as otherwise, the base capability is quite lackluster.

The menus from the unit were unstable on my (computer) monitor. Maybe there is something wrong with my setup but I suspect there is an issue with the AVR. This did not impact the audio performance though.

Testing is focused on Front Right & Left channels -- either through pre-out for DAC performance and speaker terminals for amplifier.

Peering inside, the heatsink is extruded which is good although the fins are quite thin. There is a fan on top which never came on. If it did, it would mostly cool the center of the unit rather than the amplifiers on either side of it. Likely there to pass regulatory tests.

Pioneer VSX_LX505 DAC Measurements
For this test, I feed the AVR either HDMI or Toslink digital input and measure the output using "PRE OUR" RCA terminals. I worked to optimize the pipeline to remove the effect of internal processing and adjusted the volume control to get 2 volts nominal out. This required setting the volume control to +2 dB.

View attachment 255471

This is reasonable performance for an AVR:

View attachment 255472

I also tested Toslink which produced same performance although with less spurious tones:

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I continued testing Toslink (except for Multitone) as it avoids the issue of downmixing with multichannel HDMI in my setup. In case you are wondering about the performance at different output levels, here they are:

View attachment 255475

I was positively impressed by lack of clipping here that we routinely see in other AVRs that do NOT have an option to turn off the amplifiers. Turns out this comes at a cost of another major subsystem. See the amplifier tests later.

Here is our SNR:
View attachment 255474

IMD test shows good levels of distortion but by 2-channel stereo systems, we have fair bit to go as far as noise floor:

View attachment 255476

Multitone test shows the low levels of distortion again:
View attachment 255477

Linearity is again, good for an AVR:
View attachment 255478

Jitter performance was poor for either digital input but for different reasons:

View attachment 255479

DAC reconstruction filter shows lackluster attenuation of out of band noise:
View attachment 255480

Frequency response is good enough though:

View attachment 255481

Overall not a bad showing for an AVR as far as its DAC is concerned.

Pioneer VSX-LX505 Amplifier Measurements
First in testing the amplifier is whether the analog and digital inputs perform the same. If the DAC is much better than the amplifier, then they should be the same and that is what we see here:

View attachment 255483

View attachment 255484

This makes testing easier as I can compare the results to other external amplifiers we have tested. Here is how the SINAD compares to other AVR amplifiers:

View attachment 255486

So rather weak and inline with other Pioneers I have tested.

Frequency response in Pure Direct is nice and wide:
View attachment 255487

I was disappointed to see the levels drop though when I took it out of Pure mode and subject the pipeline to digitization. Another disappointment was crosstalk:
View attachment 255488

Multitone performance lands in the same domain as SINAD:
View attachment 255489

Here is our SNR/dynamic range:

View attachment 255490

Turns out the measurement on the right is understated as you see below.

At this point I ran my 4 ohm power sweep and was stomped to see that there was so little power available (red lines):
View attachment 255493

The unit is rated at 120 watts and I was just getting 20 watts! No amount of reading the manual and searching showed any kind of "eco mode" that would limit power. After trying many things I remembered the same issue in other Pioneer AVRs such as VSX-LX303. That AVR would limit its output power after 30 seconds or so:

I repeated the same test, picking 44 watts of output and monitoring the amount of distortion. If the amp pulled back, that would be in clipping region and hence distortion would shoot way up just as above. And that is what it did:

View attachment 255497

As we see, it pulls back around the same time. This time the AVR was running pretty cool indicating this limiting is time based, no environment. You only have your maximum power for 35 seconds after which, power is limited until you power cycle the unit!

During my DAC testing, I went past the 35 seconds with volume cranked up causing the amplifier to run in power limiting. This explains why DAC performance was not dragged down with higher output voltages.

Because of this power limiting, I could not run my max and peak power ratings as that test forces the amplifier into clipping back and forth which obviously does not work. But here is the standard sweep:
View attachment 255498

This is a total fail in my book. An amplifier rated for 120 watts should be able to produce that dynamically without pulling back by a factor of 5. To have a timer of sort to reduce power is just wrong, especially since no notice is given to the customer either in the unit, or sales material.

Conclusions
The VSX-LX505 produces average performance in DAC department for an AVR. But fails on multiple fronts in amplification. No way should an AVR amplifier have any kind of timer to reduce power. This is the third Pioneer AVR I have tested to do this and is totally unacceptable. I can see this helping them with power dissipation and unit reliability but it better be told to the potential customers. FYI when my own Pioneer AVR did this, I sent a link to the review to the support line of the company and did not receive any response. So I am not hopeful that they care either.

I cannot recommend the Pioneer VSX_LX505 unless you are using it as a processor and find a way to force the unit to go into power limiting.

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I think we should call the idea of an AVR with honest, competent technical execution "Godot," because I keep waiting for it, but it never comes.

With most of them, what we see seems like sloppiness, cost-cutting (especially on engineering time) and lack of attention to signal path optimization. This problem reminds me of the Volkswagen diesel emissions scandal - someone made a conscious choice to fake meeting the published specs.

Unforgivable.