Yamaha A-S701 Stereo Amplifier Review

[Berkut]

A review of the A-S500 and some crude measurements from down-under : https://www.audiosciencereview.com/...mplifier_review_and_test_lores1-2-pdf.128151/. I guess the 501 does well, and might even be a better spot if you already use an external DAC. I love good value for money. Good sound comes cheap, better sound comes somewhat expensive. Insanely expensive does not come with good sound in general.

 

[Borko]

The phono input circuitry is basically the same across the range from 300/301/500/501/700/701.

A-S701 phono stage:
View attachment 376028

The big issue of course is the overload characteristics due to the 5V supply rails and the following AVR chipset input limitation issues. The 701 phono overload is rated at 45mV (or more), which is absolutely atrocious. I tested the 300/301 -same circuitry but with much higher rails for the phono stage:

A-S300/301 phono stage (note the higher supply rails on the same circut):
View attachment 376030

It overloaded a 74mV@1kHz, which was dead last in a test of a dozen phono stages. To put in perspective, that is about half what even a cheap 1970s integrated would offer.

That said, the phono stage was very quiet (low noise) and sounded OK.

The entire range is built around 1990s Yamaha TopArt amplifiers (which is good), they've strapped on a cheapish D/A, used AVR chips for all the switching/routing and electronic volume (the volume pot is an input device to an A/D in the chipset) and run the entire thing from a custom uP.

They are great value and work well, but they aren't SOTA. You really have to step up further along Yamaha's range to get something special.

What would you tell about Lehman Audio, a dedicated phono stage ?

Decade < Phono Stages < Lehmannaudio

A milestone among the phono preamps: The Lehmannaudio phono stage Decade forges a link between the Black Cube series and the top-of-the-line model Silver Cube. Owing to its cutting-edge technology, it spoils even the most demanding music enthusiasts.

www.lehmannaudio.com

It has maximum input level 45 mV (1 kHz) for MM. That overload margin is less than 20 dB ref nominal MM cartridge output of 5 mV (5 cm/s).
And this phono stage is not a cheap one. It is not only Yamaha with small overload margins.
I remember back in the vintage days one could not find an integrated amp with less than 150 mV max input voltage for MM phono.

 

[Spoofer]

Great review @amirm, thanks!

Can anyone comment on the usefulness of loudness - pardon me for the question - I know that this contradicts with the ideal of an amp not to mess around with the input signal ...

I own the 801. The loudness control is great if you want to custom the music by toning the loudness down. I do it at family gatherings etc, where you want to hear the music, but not let it dominate.

 

[DearSX]

Great that we can see Yamaha makes amps with good performance, looks and reasonable prices. Would love to see some blind tests of this amp vs amps costing 100 times the price.

 

[AudioKC]

Such a great AMP! Good for classic Japanies manufacturer.

Features, performance, good looking. Love it

 

[peng]

And you have checked that the level was matched within 0.1dB, I guess. Otherwise, the A/B test is pointless.

I am not sure if 0.1 dB is necessary for some, or many people. For me, probably even 0.5 would be fine.

 

[beagleman]

I had an AS 500, the weaker brother of the 700.

At that time, I had a Klipsch speaker with all that brightness, and when I started using a Marantz NR1504, I felt the sound got warmer.

As someone who always trusts measurements, I’d like to ask: What indicates the difference I heard between those amps?

When I looked around, I saw a common belief that some Yamaha models are “bright,” which is something I experienced myself.

They are not bright though. That is just some thing I see repeated with some "audiophile" types.
Every Yamaha I have used, was nearly Ruler flat response wise. And yes I measured them. There was so little deviation it would have almost NO sound character of its own.

 

[tomtoo]

I had an AS 500, the weaker brother of the 700.

At that time, I had a Klipsch speaker with all that brightness, and when I started using a Marantz NR1504, I felt the sound got warmer.

As someone who always trusts measurements, I’d like to ask: What indicates the difference I heard between those amps?

When I looked around, I saw a common belief that some Yamaha models are “bright,” which is something I experienced myself.

What was your source? Phono ?

 

[tomtoo]

A not so expensive amp that does what a amp should do.
I love things like that.

 

[caioferrari]

They are not bright though. That is just some thing I see repeated with some "audiophile" types.
Every Yamaha I have used, was nearly Ruler flat response wise. And yes I measured them. There was so little deviation it would have almost NO sound character of its own.

May be I’m influenced by the audiophile types. I’m totally aware of this as a possibility.

 

[tomtoo]

May be I’m influenced by the audiophile types. I’m totally aware of this as a possibility.

See as long we talk about aux ins all is easy flat. But phono ins with different cartridges are different.

 

[kelesh]

I'm a big fan of that entire A-S series. The 501, 701 and 801 seem to strike a perfect balance of design/performance/cost, while the 1200, 2200 and 3200 are their "upper tier" models which add meters, balanced inputs and a bunch of other supposedly more advanced engineering, or at least so Yamaha claims. Unfortunately, the cost of these last three rises dramatically - from 3K to 8K USD.

 

[Multicore]

My old Denon PRA-1500 has variable loudness and it behaves in the same way. The more you turn it up boosting highs and lows, the more it applies negative gain according to some type of compensation curve, more or less like we do with PEQ.
For "classic" tone boosting it has standard tone controls.

The loudness thing in Eq APO does that too. Pump up the loudness and everything's quieter. At that level it seems counterintuitive but I'm sure there's some good theory to it.

 

[DMill]

I'm a big fan of that entire A-S series. The 501, 701 and 801 seem to strike a perfect balance of design/performance/cost, while the 1200, 2200 and 3200 are their "upper tier" models which add meters, balanced inputs and a bunch of other supposedly more advanced engineering, or at least so Yamaha claims. Unfortunately, the cost of these last three rises dramatically - from 3K to 8K USD.

I think the AS series is one of the best values in audio. If you want to split the difference with the premium models check out the RN-1000A. It’s a pretty amazing offering at $1800 IMO

 

[caioferrari]

I think the AS series is one of the best values in audio. If you want to split the difference with the premium models check out the RN-1000A. It’s a pretty amazing offering at $1800 IMO

Agreed!

The RN-1000A has YAPO, which is great. Usually we have to spend money on receiver with a lot of channels to have a decent EQ resource.

 

[GandalfTheAudiofool]

I think the AS series is one of the best values in audio. If you want to split the difference with the premium models check out the RN-1000A. It’s a pretty amazing offering at $1800 IMO

Speaking of which, besides the HDMI ARC input which the R-N1000A has, the R-N800A looks pretty similar and is quite cheaper. The R-N1000A has a double bottom chassis, slightly better terminals, HDMI ARC and 2 coax in instead of 1 but... That's it? All the specs look the same. And the R-N800A is quite cheaper.

I'm wondering if the added 500 EUR / USD of the R-N1000A compared to the R-N800A is worth it for, basically, an HDMI ARC input which may or may not work with my LG TV and which is, anyway, not the thing I plan to use the most!?

Same DAC, same rated output power, same YAPO, etc. They look very similar.

If anyone has any thoughts on the R-N800A vs the R-N1000A, they're very welcome for I really need an amp to go with my new speakers (not to mention the old amp I'm currently using is going to go back to power my old speakers so I need it there).

 

[Dalprad]

Great review @amirm, thanks!

Can anyone comment on the usefulness of loudness - pardon me for the question - I know that this contradicts with the ideal of an amp not to mess around with the input signal ...

I have this amp and I'll give you my take on the loudness. As you turn it counter clockwise it essentially reduces the midrange and gives the amp a scooped sound. It is very useful at low volumes where you would normally lose any sense of bass. To me, when the loudness is dialed all the way to left, it sounds like someone is blasting the stereo behind a closed door. So it gives you the feeling the the stereo is being played loudly, but behind a wall or at your neighbor's house. It's weird, but useful at ultra low volumes. I also find it useful on hard rock and metal where that scoop sound just suits the usually poor and harsh recordings. I use it a lot more than I expected and don't hear a much if a change in sound quality.

 

[Dalprad]

Would it pair nicely with Revel M16s? Is there a better choice for those speakers in the <2500€ (for an amp+speakers set) price range? And a noob question (never had a passive setup): what is the best impedance setting for 6 Ohm speakers like the M16? It looks like it says 'A or B' on the backplate above the switch?

I use it with the M106 and it's great. Good match and powers them easily.

 

[amirm]

DAC and Phono measurements added to the review. Sadly both are subpar.

 

[amirm]

I note you've tested at 245mV and an arbitrary 1.6V??

It is not arbitrary. My new standard for amplifier gain is 25 dB. Getting 5 watts output then requires 0.245 volts. And this amp clips at 1.6 volts input at that gain. This is into 4 ohm. My old standard was 29 dB which was NOT in keeping of much higher output voltage we have available from our sources.