Are you talking about the Denon's graph only shows up to 2 V. If it is, it is only because Amir typically test pre outs to 2 V RCA, 4 V XLR but occasionally he would test to a higher voltage, such as the case of the RZ 50.
Here's one time he tested with higher voltage for an Denon, the X6700H, that has the same volume control and DAC ICs:
Note that Audioholics.com's Gene has also measured the lower model, the AVR-X3300W up to 4.5 Vrms unclipped (so he said). Again, I think while one measures much better, I do realize audibly speaking it could be a moot point under "normal" use conditions.
No - sorry about the confusion - I was referring to the other test of the 3700 - where the pre outs were tested with the internal amplifiers on.
It clipped at 1.4V - whereas with the amplifiers off, it had plenty of headroom.
To me that would rule it out, as my power amps are pro/XLR input levels... so the signal required for Max/rated power out of the amps, is 1.4V RMS - with peaks out to around 2V or a smidge over.
Were I using my Quad 606 power amps, with signal input of 0.5V RMS for rated ouput - this would not be a concern... but with my current speakers, the Crown XLS's sound better.
In any case, this is a known weakness of the Denon design - measure here.
For the end user that uses solely external amps, - not an issue. For the user that uses solely the internal amps, also not a problem, but if you want to run a hybrid setup with external amps for the L/C/R and internal amps for surround/heights - then you need to think carefully - and potentially limit your choice of amps to ones that take an appropriately (low) signal level.
In the overall scheme of things - the 96db SINAD of the RZ50 is within the range I consider acceptable (would I like to see more/better? - sure... but we are definitely reaching past the limits of audibility in a domestic environment!) - whereas the V out being within the right range to mate with my power amps is an absolute requirement....
I have just finish a quick/rough installation of the RZ50's baby brother the Integra DRX 3.4 in my setup... the DIRAC REQ has made an immediately noticeable difference - detail in the midrange is immediately more obvious/clear, voices / dialogue are much easier to hear.
It has replaced a 2013 Integra DTR 70.4 powerhouse... which when new, cost more than double the price, weighs 30kg, has excellent amps - and the Audyssey never did a great job in either my previous home or current one.... (in both environments the AVR sounded best on its own without Audyssey engaged). - to be fair, the new "tunable" Audyssey might have resolved the issue.... or not. The new Integra looks small alongside the hulking mass of the old Receiver.... but it sounds better.
As a balancing act between affordability, and features, with more than adequate performance, I think the current Onkyo/Integra/Pioneer family are hitting the target dead center. At local pricing right now, the Denon X3700h is around 50% more expensive than the Onkyo... although there are indications that Onkyo is going to raise its prices. (Get them while their hot!?)
P.S. the X3700 was the only alternative I was seriously considering other than the Onkyo/Integra/Pioneers.... wanting to try Dirac, after my failures with Audyssey was key - but the preout voltage issue was also an important factor against it, in my case.
