I believe that most people who buy AVRs don't need external amps because they don't usually listen loud enough, sit far enough, or own very expensive speakers with impedance that dip too far south.
I would not recommend audio gear based on the premise that only expensive speakers have impedance dips!
A speaker that has been very popular in the budget to mid range market is the
Andrew Jones Uni-Fi UB5 speakers at $500 a pair. It is rated at 4 Ohms with 3.2 Ohm minimum and 85dB efficiency. Is that "too far south"? I sure would rest easier buying an AVR with a little high current capability, especially since it would only cost $100 more for the Denon X3400H which appears to be at least twice as strong at lower impedance!
The situation is also complicated because we know speaker impedance ratings from manufacturers are often bogus!
The A860 can output 100W x 2Ch into 8 ohms 20Hz-20kHz at 0.1% THD (AH lab).
Wouldn't it be great if it could put out decent power at 4 Ohms?!
The "lowly" $600 MSRP Denon AVR-X1200H measured as follows per Sound & Vision:
0.1% THD 1.0% THD
2 Channels Continuously Driven, 8-ohm Loads 112.8 watts 126.1 watts
2 Channels Continuously Driven, 4-ohm Loads 139.2 watts 164.3 watts
5 Channels Continuously Driven, 8-ohm Loads 69.9 watts 78.8 watts
7 Channels Continuously Driven, 8-ohm Loads 47.4 watts 57.9 watts
Read more at
https://www.soundandvision.com/content/denon-avr-x1200w-av-receiver-review-test-bench#587kbzpmQmMl1sRQ.99
Here are my take-aways on this thread:
1) The Denon pre-pro you bought was more than a flagship, it was on the cutting edge of what a pre-pro could reasonably be! Denon is a large modern company with a good QC department with competent test facilities, and the Japanese are good at it; but unless a product is an incremental modification of a well established product, the ability to predict lifespan of a product which is a departure from the norm beyond 5 years becomes a real crap-shoot. This unit served you 5 years beyond the 3 year warranty period, I suspect Denon was hoping for better, but given that they discontinued it without an updated replacement, it is clear that they determined it not to be a viable product.
You got burnt, it wasn't you fault. You can look at it as an experimental model that passed all of the tests they had to evaluate it, but in the end the only way to establish how viable it is is to produce it and see.
For many customers, 8 years was enough; as features like Atmos or 4K would have pushed an upgrade. It seems like Gene upgraded his before problems arose(IIRC?). I also suspect that you used yours many more hours per day than most customers, so depending on failure mode, there may be plenty still working fine. 8 years for you may equate to 12 or 16 for someone who doesn't listen as regularly as you do (assuming it is total operating hours that kills it)!
Your experience with this product is disappointing, but I think it is an experience that is more unique to the Denon AVP-A1HDCI pre-pro than categorically to D&M.
2) I believe the Yamaha units you currently have fall into the "well-established" product category, and not the "experimental design" category, so I would expect you to get more service out of them than the Denon AVP-A1HDCI. I envy you for the Yamaha separates you have! They are top level gear from my perspective!
3) There is no perfect manufacturer! Yamaha may have, until recently, been the best of the bunch, but, even then, not by any decisive margin. Throughout this thread, you have primarily been singing the praises of Yamaha. However, right now, I would consider it prudent to avoid buying a Yamaha AVR near, at, or below the $900 860 without doing
a lot of research of the details of both the AVR and the speakers/application. To me, it is clear that Yamaha produces an inferior product for the price of their 860, and we don't know which other products by Yamaha may have the same design philosophy. It is hard to know for certain exactly how much power you will need and I often look at an AVR like the 860 (assuming I had not read Gene's review) and think "well, worst case, it has pre-outs so I can always add an amp if need be", so it is even more disturbing to know that the pre-outs are compromised from the norm! From my perspective the situation with the A860 reflects more poorly on Yamaha than the Denon AVP-A1HDCI pre-pro does on Denon! You are probably right that the A860 will be ample for many consumers, but now that you know it lags behind the competition (including its predecessors),I hope you would not give it your recommendation. I would be comfortable suggesting it to someone buying a mid-range Klipsch system, but otherwise, I would just take it off of the table!
With that said, I still believe Yamaha makes some very excellent (and maybe, the best) products at the high-end, but I will stay wary of their budget/value products!
