Pioneer VSX-LX505 Power Remeasurement

[SorenTyson]

Great work from Amir to expose this. It allows us to be informed buyers.

I don't see the protection as a bad thing per se, as I think it will not be triggered by normal use.

However the big no-go is that the receiver doesn't show it and allows you to turn it off

I bought the rz50 after reading the review, with the intention of adding buckeye poweramps. Anecdotally I never needed additional power, and haven't noticed if the Onkyo ever activated the protection

 

[JSmith]

normal use

One persons normal use may not be another persons.


JSmith

 

[SorenTyson]

One persons normal use may not be another persons.


JSmith

Agree, and that's where the value of this site pops up. If your normal use would trigger this, then buy another receiver or pair it with Poweramps.

It's a HT receiver so I would say normally paired with a sub, can we calculate how much a sub offloads the receiver amps (genuine question)?

 

[JSmith]

then buy another receiver

This sounds like the best option... I mean we have some of the Denon models that perform very well and don't have this "issue".


JSmith

 

[Bleib]

We need to keep Denon alive and well for the benefit of mankind

 

[EWL5]

This sounds like the best option... I mean we have some of the Denon models that perform very well and don't have this "issue".


JSmith

My first Denon is the 3800 and it has performed admirably in ~3 years of ownership. It says "hold my beer" during the 4 ohm test.

 

[audioje]

Using lx102 for more than 7 yrs. I kinda knew but now i know better-how little power I need. I only paid $200 for new and no complaints at all. BTW, better brand recommendation for my future purchase? Denon and Onkyo?

 

[Bleib]

Using lx102 for more than 7 yrs. I kinda knew but now i know better-how little power I need. I only paid $200 for new and no complaints at all. BTW, better brand recommendation for my future purchase? Denon and Onkyo?

Denon, quite many reviews here @ ASR

 

[Svetlio]

And Pioneer charge about 1300 euro for this faulty AVR, tc, tc, tc.....shame.

 

[DearSX]

Love seeing a product I owned years ago and updated from, tested. Thanks Amirm!

 

[Miker 1102]

Thank you for doing this. I know many users reported not having this issue from day to day use. I think it was great that Amir retested anyway. I have learned so much from being a member here.

 

[Miker 1102]

I ran a LX305 for many years in 5.1 and 8 ohm setting without any problems that I could tell. Once I added the height speakers then after a few minutes I could hear a relay click in the unit, presumably switching to the 4 ohm setting. If I configured it for 4 ohm then no relay click. Eventually I upgraded to a X4800H with an external A70 amp to 7.1.4 and that was a huge improvement. Plus all the extra configurability over the 305 was nice to have, especially being able to set individual crossovers for wildly different speakers. The 305 got moved to the office where Dirac really helped with dubious in ceiling speakers.

The crossover thing was a big reason why I returned it. You could only set the pairs to like 40, 60, 80hz..I did not understand that.

 

[Miker 1102]

Not all of them are doing this power limiting. The engineers have tuned the nannies too aggressively which we have seen in past for example with Yamaha Aventage models. In case of Yamaha i have not seen anyone complaining in real life even when pushed close to reference volume. No protection kicking in or sound hardening which usually happens with lower cost AV-receivers which runs out of power. The earlier model VSX-LX504 does not power limit in AudioVision bench test nor the RZ50. The power output figures are almost identical to Denon X4800H.

VSX-LX505, RZ50 and the X4800H are all fitted with 2x 15,000μF main block capacitors and the power transformers size / VA spec should be very close as they measure so similar.

Pioneer`s flagship LX805 shows bigger jump in power. The sister model to RZ70 and Integra. Power numbers are similar to Denon A10H.

Yeah. There was a bench test of the R70 and it delivered serious power. Its a beast though. 50 pounds.

 

[Miker 1102]

The measurements provided by @Synthethesiscinema are clearly showing that the Onkyo/Pioneer/Integra are able to provide enough power to drive the speakers.
The problem is what speaker type will trigger the nannies in real life.
The load of a speaker is a complex impedance and only a real test can show what happens.
The load of my tower speakers are two 8" woofer Dayton SD215A88 with a minimum impedance of 3.20 Ohms around 150 Hz according to the datasheet.
As I have connected them in serial mode the minimum load impedance seen from the RZ30 is 6.40 Ohms.
The RZ30 is driving them properly at moderate sound level (apartment in a condominium).
It was not the case for the Yamaha RX-A700.

Here is the important question, as ASR is an audio forum:
Could a user of Onkyo/Pioneer/Integra explain how he succeeded to trigger the limp mode when listening music?

I have been haunting the threads for years now and have never seen a post. I would like to know.

 

[dlaloum]

Then why doesn't indicate it has entered this mode when protection really kicks in? Why pretend the amp is still fully functional?

As I have mentioned before - I believe it does report that mode, in the web status screen - where it also reports fan operation and measured temperature...

 

[Miker 1102]

As I have mentioned before - I believe it does report that mode, in the web status screen - where it also reports fan operation and measured temperature...

No mentions of this flaw anywhere but testing far as I can tell. As you have pointed out on the past, if it doesn't behave this way in use . So, a 9.2 chammel Avr that comes with full band Dirac with full pre outs for less than 800 dollars is nothing to sneeze at. I learned more about room correction and acoustics over the last two years and think this maybe an unbelievable value for a pre amp.

 

[dlaloum]

Hi Folks,

Up until 2 months ago I owned the Integra DRX3.4 (Integra version of the NR7100/LX305, and very very close relative to the RZ30)

What I found was that although it had enough power to handle my setup and speakers (I don't listen all that loud, and measurements/calculation has shown that my continuous power needs are between 1W and 4W, and my peak has never exceeeded 16W !!) - it did not interact well with my Gallo Ref 3.2 speakers - these speakers have a capacitive tweeter which drops down to 1.6ohm, and the woofer crossover drops to 3 ohm. (they are rated as 4ohm nominal)

In actual use, the midrange sounded "muddled" it lost most of its imaging, and vocals / dialogue was unclear.

Using the same unit as a prepro, hooked up to amps that I know can handle my speakers properly (Quad 606 and Crown XLS2500) - this muddling disappeared, imaging was excellent, dialogue/vocals were very clear.

Note: it never went into protection. (The Web status screen, provides an indicator of protection mode, along with fan speed and temperature monitoring)

However I suspect that this amplifier design does not handle the 1.6ohm capacitive load of the tweeter, resulting in increased distortion and subjective effects described.

I also suspect (but have no objective evidence) that the RZ50/LX505/DRX5.4 would most likely suffer from the same issue as they all use the same base amp design.
I would expect the RZ70/DRX8.4/LX805 would probably not suffer from this issue (certainly their previous generation ancestors the Onkyo SR876, and Integra DTR70.4 both handled these same speakers without any issues!)

As a contrast my current Denon X4800 - which is quite similarly specced in power terms to the RZ50/LX505/DRX5.4 - handles my speakers properly, and has allowed me to retire my external power amps.

Additional Information point:

With the Integra DRX3.4, driving a pair of B&O Beovox Penta speakers - which are an 8ohm design, much easier to drive.... there was no issue, and the sound was as it should be (along with imaging, vocals, dialogue etc...) - so the issue was totally down to its ability to handle a specific type of reactive speaker load.

With most speakers (even 4ohm ones) I am sure the Onkyo/Integra AVR's will handle them just fine - but some of us have oddball speakers which for various design reasons, present difficult loads to the amp, and the RZ30/RZ50 (and siblings) are not well suited to such speakers, however I expect the RZ70 would probably do just fine.

 

[JSmith]

It's not to protect speakers... it's to protect the amp from letting out the magic blue smoke, i.e. no returns, or worse.

It’s not behaving like a speaker protection limiter... it’s behaving like a self preservation cutoff.

The amp is hitting its internal thermal/current limits and shutting down before it cooks itself… so what does that say about this product?

But hey, if people think this is ok as it's not "triggered in normal (undefined) use"... all the power to you (pun intended).


JSmith

 

[dlaloum]

It's not to protect speakers... it's to protect the amp from letting out the magic blue smoke, i.e. no returns, or worse.

It’s not behaving like a speaker protection limiter... it’s behaving like a self preservation cutoff.

The amp is hitting its internal thermal/current limits and shutting down before it cooks itself… so what does that say about this product?

But hey, if people think this is ok as it's not "triggered in normal (undefined) use"... all the power to you (pun intended).


JSmith

If it was reaching some sort of thermal limit - you would expect to see the temperature rise in the Web Status screen... (and the fan would speed up as well - also reported on that status screen)

 

[amirm]

As I have mentioned before - I believe it does report that mode, in the web status screen - where it also reports fan operation and measured temperature...

That's not a valid report. If you are saying it is like protection mode, then it should be displayed as such. On the front panel and with LED indications.