Yamaha A-S801 Integrated Amp unites analog and digital audio

P

PENG

Audioholic Slumlord
Yeah, I guess the difficulty was I was trying to go straight to the Test Results which is a pdf file.

However, my point was that I'm not sure what it is that you intend to measure/establish that was not already covered by those tests.
Do you think your A-S701 has a different amp section than the A-S700?
I am almost certain they have the same amp section.
Edit: Good thing I said "almost". The amp specs are similar but different, the amp section would be similar but different.

This thing is only rated:
Minimum RMS Output Power (8 ohms, 20 Hz-20 kHz) ..............................100 W
Minimum RMS Output Power (6 ohms, 20 Hz-20 kHz, 0.038%THD)..........120 W
Maximum Power (4 ohms, 1kHz, 0.7% THD, for Europe)............................160 W

Note that the 4 ohm rating is stated as "Maximum" and for 1 KHz and much higher THD, so I will not consider this as a truly 4 ohm rated amplifier, though it should have no trouble driving 4 ohm speakers with dips to even 2 ohms as long as the user stay well below 100/50 W, assuming the amp does not have a low impedance sensing protective circuit.
 
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T

trl

Enthusiast
Thank you!

I was looking over its schematic and one thing’s for sure: this amp has lot of internal protections and their thresholds can be adjusted from firmware via CD-ROM (both output stage heatsinks temp, bridge rectifier temp, power transformer temp, output DC).
 
KEW

KEW

Audioholic Overlord
That's all good, until the day (maybe coming, maybe not..) when manufacturers start to implement low impedance sensing in their protection algorithm across the board, just because there are enough idiots (hopefully not..) making warranty claims.
I'm going to be optimistic and hope the manufacturers can either deny such claims on the basis that the owner violated the specific warning printed on the back panel, or that such an automated limiter would monitor temperature changes and load to better maintain power until protection is warranted instead of a dumb "always on" switch.

Gene used the analogy of permanently setting your V8 engine to run on 4 cylinders in economy mode.
I think a better analogy is to always limit your car to 15MPH because you are oblivious to your surroundings, so must accommodate the possibility of ice patches on the road in your decision of how fast to drive safely!
If the impedance control can include a little awareness of the operating state of the amp, it could make intelligent decisions instead of being permanently set for the worse case!
 
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P

PENG

Audioholic Slumlord
I'm going to be optimistic and hope the manufacturers can either deny such claims on the basis that the owner violated the specific warning printed on the back panel, or that such an automated limiter would monitor temperature changes and load to better maintain power until protection is warranted instead of a dumb "always on" switch.

Gene used the analogy of permanently setting your V8 engine to run on 4 cylinders in economy mode.
I think a better analogy is to always limit your car to 15MPH because you are oblivious to your surroundings, so must accommodate the possibility of ice patches on the road in your decision of how fast to drive safely!
If the impedance control can include a little awareness of the operating state of the amp, it could make intelligent decisions instead of being permanently set for the worse case!
 
P

PENG

Audioholic Slumlord
I'm going to be optimistic and hope the manufacturers can either deny such claims on the basis that the owner violated the specific warning printed on the back panel, or that such an automated limiter would monitor temperature changes and load to better maintain power until protection is warranted instead of a dumb "always on" switch.

Gene used the analogy of permanently setting your V8 engine to run on 4 cylinders in economy mode.
I think a better analogy is to always limit your car to 15MPH because you are oblivious to your surroundings, so must accommodate the possibility of ice patches on the road in your decision of how fast to drive safely!
If the impedance control can include a little awareness of the operating state of the amp, it could make intelligent decisions instead of being permanently set for the worse case!
Not control, just sensing. The hardware's already built in, just need a little firmware mod. Yamaha seems keen on AI and not shy on adopting aggressive protection too, so they may be first on this.
 
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T

trl

Enthusiast
They can probably do that, but only while powering-up, then relays will commute the correct voltage from the power transformer and after few seconds the output stage will get directly connected to speakers. So, we will all have 8 Ohms resistors on B-speakers and 4 Ohms speakers on A-speakers; while the amplifier will boot-up we'll switch to B-speakers for few seconds, later we'll switch to A-speakers, so mission accomplished. :)
 
P

PENG

Audioholic Slumlord
They can probably do that, but only while powering-up, then relays will commute the correct voltage from the power transformer and after few seconds the output stage will get directly connected to speakers. So, we will all have 8 Ohms resistors on B-speakers and 4 Ohms speakers on A-speakers; while the amplifier will boot-up we'll switch to B-speakers for few seconds, later we'll switch to A-speakers, so mission accomplished. :)
The voltage and current signals are already reporting to the CPU, so continuous monitoring of the impedance is theoretically possible. I am not fond of the idea, just saying they can do it if they wish to.
 
J

JW001

Audiophyte
Thanks for the review! I don't quite agree with this statement, though: "Overall the A-S801 has a very good headphone preamp so I recommend utilizing it if you've got some good cans."

I measured the output impedance of one channel of the headphone jack: it's a whopping 450 ohm. Although overall I like the amplifier, the headphone output sounds horrible on both 300 ohm Sennheiser HD600 and 23 ohm HD598. I certainly wouldn't recommend A-S801 for its headphone feature... It's implemented through a voltage divider from the main output. An afterthought, like with most AVRs.
 
E

<eargiant

Senior Audioholic
Thanks for the review! I don't quite agree with this statement, though: "Overall the A-S801 has a very good headphone preamp so I recommend utilizing it if you've got some good cans."

I measured the output impedance of one channel of the headphone jack: it's a whopping 450 ohm. Although overall I like the amplifier, the headphone output sounds horrible on both 300 ohm Sennheiser HD600 and 23 ohm HD598. I certainly wouldn't recommend A-S801 for its headphone feature... It's implemented through a voltage divider from the main output. An afterthought, like with most AVRs.
It didn't sound special to me either.
 
T

trl

Enthusiast
It has no dedicated headphones amplifier, just two simple 470 Ohms/1W resistors, a RC low-pass filter and couple of diodes reverted in parallel for DC-protection, nothing else.

A-S1xxx/2xxx/3xxx have dedicated headphones amplifiers inside, which is normal given the higher price.

P.S.: I am enjoying my A-S701 on speakers, but for headphones I'm using a dedicate amplifier.
 
K

kenwstr

Audioholic Intern
Yeah, always been a 2 ch guy, had several integrated amps over the years. Currently running a Yamaha A700, 0.005%THD by the way. Had it serviced/upgraded by Bill Crampton, Canberra ACT Australia, Great guy. For digital sources, I have an Essence HDACC wired into one of the amps tape dubbing loops to provide remote volume control for the family. As it's in the loop, it functions with every source. Technically not pure I know but it is practical functional simplicity. I can still switch any of the analogues sources through to direct path if I wish. The digital sources just play into the tape input which is direct for them. This seems a very practical solution to integrate a vintage amp and digital sources together. So, the A-S801 with an inbuilt high end DAC is a real plus.

Can't say I'm doing analogue much these days. Gradually replacing the LPs with CD and ripping in EAC, it's just more convenient to select and play from a network drive. I do some streaming too but tend to buy and rip CDs when I find something I like. Other Amps I have include Pioneer A400, A400x and some nondescript ones, RankArena RA 80A (free) and others I don't recall. However, the restored A700 matched with Polk 10Bs is just a delightful vintage sound that lifts my soul.
 
P

PENG

Audioholic Slumlord
Yeah, always been a 2 ch guy, had several integrated amps over the years. Currently running a Yamaha A700, 0.005%THD by the way. Had it serviced/upgraded by Bill Crampton, Canberra ACT Australia, Great guy. For digital sources, I have an Essence HDACC wired into one of the amps tape dubbing loops to provide remote volume control for the family. As it's in the loop, it functions with every source. Technically not pure I know but it is practical functional simplicity. I can still switch any of the analogues sources through to direct path if I wish. The digital sources just play into the tape input which is direct for them. This seems a very practical solution to integrate a vintage amp and digital sources together. So, the A-S801 with an inbuilt high end DAC is a real plus.

Can't say I'm doing analogue much these days. Gradually replacing the LPs with CD and ripping in EAC, it's just more convenient to select and play from a network drive. I do some streaming too but tend to buy and rip CDs when I find something I like. Other Amps I have include Pioneer A400, A400x and some nondescript ones, RankArena RA 80A (free) and others I don't recall. However, the restored A700 matched with Polk 10Bs is just a delightful vintage sound that lifts my soul.
I compared the specs and glance through the schematics of the A-S700 vs the A-S701/801 and got the impression that it is a superior amp in terms of being more "pure bred" integrated amp. The 701/801 are clearly AVR related, i.e. cousins, though are obviously better build and implemented even with many shared parts.

That said, I suppose only golden ears can tell a difference in sq between those 3.
 
O

onyx cat

Audioholic Intern
I used to sell hi end audio in the 70's , remember the Yamaha amps and receivers were hard to beat for the money , we had B&O, and Tandburg electronics as well but I likes the Yamaha stuff better and it was also lower cost , the only product better was McIntosh and I love the McIntosh gear and used to own it as well but I am retired now and just getting back to Audio , I may not live long enough to get my moneys worth out of MAC gear , but would love to still have it . Now I have a Yamaha 301 Int. Amp and going to upgrade it to a 801 , have polk Audio speakers ( OK for Now) , Thornes TD125 turntable and 3009 SME arm and Ortofon bronze , I would like to find a new stylist for my Ortofon M15e but seems like Ortofon does not make that anymore , stream from a Sony blue ray and also have a old tuner I put together from a kit ,a HH Scott LT112 , still works OK . My system now is OK but I do get this harsh sound from the tweeters on streamoing , tried some other tweeters and now a little better but still has the problem , maybe my streamer? , maybe the new 801 Yamaha amp may help as it has a better DAC …
 
Pogre

Pogre

Audioholic Slumlord
I used to sell hi end audio in the 70's , remember the Yamaha amps and receivers were hard to beat for the money , we had B&O, and Tandburg electronics as well but I likes the Yamaha stuff better and it was also lower cost , the only product better was McIntosh and I love the McIntosh gear and used to own it as well but I am retired now and just getting back to Audio , I may not live long enough to get my moneys worth out of MAC gear , but would love to still have it . Now I have a Yamaha 301 Int. Amp and going to upgrade it to a 801 , have polk Audio speakers ( OK for Now) , Thornes TD125 turntable and 3009 SME arm and Ortofon bronze , I would like to find a new stylist for my Ortofon M15e but seems like Ortofon does not make that anymore , stream from a Sony blue ray and also have a old tuner I put together from a kit ,a HH Scott LT112 , still works OK . My system now is OK but I do get this harsh sound from the tweeters on streamoing , tried some other tweeters and now a little better but still has the problem , maybe my streamer? , maybe the new 801 Yamaha amp may help as it has a better DAC …
You know, if it's been a while and you're just returning DACs have come a long way and most competent manufacturers have it licked. Even some of the higher end AVRs have very good DACs now and most the differences now all fall below the range of human hearing. If you're considering new speakers I would address that first, before even considering a lateral move like an amp "upgrade".

I highly, highly doubt you'd be able to pick a difference between the 501 and 801 in a DBT. The extra 15 watts doesn't translate to any real audible gain in spl either. Speakers, man! Always put the bulk of your budget into the best speakers (and subwoofage) you can afford and build around those. I agree with you about Mac gear. I love it too and would love to own some, but I would buy golly make sure I had speakers worthy of it first! Right now I think you have good amplification that should be able to handle pretty much anything you throw at it. Let's start looking at speakers!
 
O

onyx cat

Audioholic Intern
You know, if it's been a while and you're just returning DACs have come a long way and most competent manufacturers have it licked. Even some of the higher end AVRs have very good DACs now and most the differences now all fall below the range of human hearing. If you're considering new speakers I would address that first, before even considering a lateral move like an amp "upgrade".

I highly, highly doubt you'd be able to pick a difference between the 501 and 801 in a DBT. The extra 15 watts doesn't translate to any real audible gain in spl either. Speakers, man! Always put the bulk of your budget into the best speakers (and subwoofage) you can afford and build around those. I agree with you about Mac gear. I love it too and would love to own some, but I would buy golly make sure I had speakers worthy of it first! Right now I think you have good amplification that should be able to handle pretty much anything you throw at it. Let's start looking at speakers!
 
lovinthehd

lovinthehd

Audioholic Jedi
I used to sell hi end audio in the 70's , remember the Yamaha amps and receivers were hard to beat for the money , we had B&O, and Tandburg electronics as well but I likes the Yamaha stuff better and it was also lower cost , the only product better was McIntosh and I love the McIntosh gear and used to own it as well but I am retired now and just getting back to Audio , I may not live long enough to get my moneys worth out of MAC gear , but would love to still have it . Now I have a Yamaha 301 Int. Amp and going to upgrade it to a 801 , have polk Audio speakers ( OK for Now) , Thornes TD125 turntable and 3009 SME arm and Ortofon bronze , I would like to find a new stylist for my Ortofon M15e but seems like Ortofon does not make that anymore , stream from a Sony blue ray and also have a old tuner I put together from a kit ,a HH Scott LT112 , still works OK . My system now is OK but I do get this harsh sound from the tweeters on streamoing , tried some other tweeters and now a little better but still has the problem , maybe my streamer? , maybe the new 801 Yamaha amp may help as it has a better DAC …
Sounds like a speaker issue....and you're changing tweeters in your Polks? What speakers do you have? I'd certainly work on speakers/room before a slight change in amplification. For replacement stylus you might check this https://www.lpgear.com/product/ORTSM15ES.html
 
O

onyx cat

Audioholic Intern
I do understand about the speakers , I am going to get a Klipch Sub woofer this week , it is on sale for 500.00 , was 650.00 , the Amp I have now is a Yam. AS301 and not a 501 , will be getting a 801 this week , will also be looking for better speakers soon as well when I can afford them , remember I am now on a retirement income . If I can swing it in maybe a year from now will get better speakers that maybe are a little "darker" to play old records and some recordings that at way to much compressed , any commits about that harshness on streaming ?
 
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