New Sony ES digital receivers have high THD! (1 Viewer)

[Chu Gai]

And it would be appropriate to note that reviewing the power curves for the Bel Canto at Stereophile one will find in Figure 10 a graph of distortion as a function of frequency into different loads (8, 4, 2 ohms). Now the BelCanto is stated by the manufacturer as being a 120 watt unit (8 ohms). However if you look at the curve, it rather abruptly ends at around 90 watts. Peculiar don't you think? It's also unclear whether the rise in distortion is solely due to the switching frequency or something else. Work is being done by some manufacturers where a 'bullet' is sent out to the speakers which will blueprint their impedance curves. The information obtained will then be somehow used in the circuitry to make the amp more speaker friendly.

BelCanto uses the Tripath chip and that chip is also licenced to Sony. Offhand I don't recall who else (Sharp I think) is also using it.

So 10 grand or not, I wouldn't wet my pants dreaming about more expensive units. Bel Canto is a small player and their prices will be substantially higher. If I were to guess, I'd think Sony's R&D or Harmon's for that matter, to get digital right before others.

With all the problems you had with the Sony receivers, notably your mentioning of crosstalk, noise in your speakers, etc. why did you keep buying them and simply not return the unit to get your money back and try something else?

 

[JackS]

Well in the end Darryl hears crosstalk and distortion in his ES receiver so he really should switch to something else, I would. There are a lot of choices so no need to put up with something that can make the complete system unlistenable and hard to live with. I had a simular experience with a two channel receiver (I've owned many) many years ago and to this day, I would never consider purchasing this brand again. I also realise that my opinion is totally unfair and that many users of this brand are very happy. Human nature I would guess, but as long as the choice are many, this particular brand will never enter my equipment rack. I think most of us have had a simular experiences and either conscious or unconsciuosly we hold these positive and negitive opinions and put them to use every time we go shopping. Good luck, Jack

 

[Chu Gai]

Ain't that the truth Jack. My father won't every think of buying Getty gas and he had a Buick back in the 50's that caused him so much grief, that 40 years later, he still had bad things to say about them. Maybe it's like that old saying, 'you only have one chance to make a first impression'.

 

[LanceJ]

Who is the "they" that says recent affordable digital amps sound bad?

Panasonic came out with their XR-10 receiver w/a digital amp almost two years ago. Never saw one professional or owner review.

Same with their new XR25 & XR45 receivers--nothing.

Harman/Kardon came out with their digital amp receiver about five months ago--again no reviews.

And by "review" I don't mean someone at Circuit City listening to a radio station with a pair of $150 Pioneer speakers with the volume at its maximum setting.

LJ

 

[DarrylM]

With all the problems you had with the Sony receivers, notably your mentioning of crosstalk, noise in your speakers, etc. why did you keep buying them and simply not return the unit to get your money back and try something else?

Mainly 'cause I was once a Sony Fanboy, like I said. For all I knew at the time, all receivers exhibited that sort of performance and I was getting the "best" there was. I even upgraded to better and better models (that is, DE to DB to ES). Eventually, though, I realized that I didn't have to settle for such substandard performance, and I did not replace my last receiver with another Sony after I sold it. I've actually been receiver-free for many months now, since I've been patiently waiting to see how well the new Rotel 1098 would perform. Otherwise, I'll probably send my money Outlaw's way.

 

[Seth_L]

Darryl,

Sony is using the same Tri-path modules that are in those critically acclaimed digital amps, so comparing them to $10k amps isn't all that unrealistic.

Good luck with the Outlaw. If you thought Sony had annoying bugs you haven't seen anything yet.

 

[Chu Gai]

There was a discussion some time back regarding digital amps and receivers here that might be of some interest and contains a couple of links to give some food for thought.

With regards to the THD, which in the manner it's typically measured, might be more appropriately called THD+N, of more interest than just the simple number would be to see what the distortion spectrum looks like under different loads. 0.7% distortion is generally considered inaudible but that makes an assumption that the distortion products are lower order non-linears like 2nd or 3rd order. In those cases, audible masking covers anything up. However, make that something like a 15th order and you'll pick it up. Things to look for in reviews, would be to see more in-depth, critical examinations of the receiver's distortion under varying loads.

 

[Gil D]

I've never heard a Sony that didn't have a high THD level, including their ES models.

I have two ES receivers, an ES CD megachanger, an ES SACD changer, with some resolving speakers and headphones and I have no idea what you are talking about. Speaker distortion and response will swamp any contribution due to electronics.

I just may have to try one of those Carver Pro amps...

 

[DarrylM]

Sony is using the same Tri-path modules that are in those critically acclaimed digital amps, so comparing them to $10k amps isn't all that unrealistic.

Just a couple of points:

1. The $10,000 TactT digital amplifier did not use Tripath modules, the Bel Canto did.

2. Tripath modules are not considered "high-end" components by any means. You can find them in inexpensive DVD receivers, television monitors, and whatever else from companies like Aiwa, Sanyo, Sharp, Apex, Samsung, et cetera.

3. There is certainly more to those digital amplifiers than just the Tripath modules. As with analog amplifiers, quality capacitors, power supplies, heat sinks, and other components are still critical to the overall performance.

4. Keep in mind that digital amplifiers, including Class T (Tripath) amps, are not used because they provide superior audio performance to analog amplifiers. They are used because they have "power efficiency, size, weight and cost advantages over traditional amplifier technology" (a quote regarding Tripath). As a matter of fact, the implication in many technical discussions regarding these products seems to be an assertion that their digital switching products sound "almost as good" as analog amplifiers. You probably won't find a review or article stating something like, "Oh, we wanted our amplifiers to sound better, so we dropped the analog components and went to digital, instead."

 

[Lewis Besze]

Good luck with the Outlaw. If you thought Sony had annoying bugs you haven't seen anything yet.

Really, can you point me to one that hasn't been fixed?

 

[Seth_L]

Really, can you point me to one that hasn't been fixed?

Sure... On a 950, go from a 2 channel stereo source like the CD input and then switch to the multichannel input. You'll notice only the front 2 speakers work. You have to switch from something using DD or DPL2 or DTS into the multichannel input to get all 7 speakers to work.

 

[DanielMan]

I think the simple fact is that digital amps are a MATURING technology. So far I haven't seen any reviews that rank a digital amp above an analog amp.

Maybe some time in the future (say 5 years?), digital amps will be equal or better than their analog counterparts. I saw a link to a review of a $15K Sharp two-channel digital amp and the frequency response curve looked terrible (especially compared next to a Mark Levinson frequency response curve).

Who knows, maybe Sony has something with their new ES line but I'll remain a skeptic for now. It surprises me that Sony would adopt digital amp technology in their audiophile line. It would make more sense to test it in their lower lines first.

 

[DarrylM]

On a 950, go from a 2 channel stereo source like the CD input and then switch to the multichannel input... You have to switch from something using DD or DPL2 or DTS into the multichannel input to get all 7 speakers to work

That's actually more of an operational quirk than a performance issue. Also, I thought there was another button on the remote that you could push to activate all 7 channels of the analog inputs after switching from a 2-channel source...?

 

[Dale B]

Hi everyone. I tried to wright a review of the Panny xr25 with the digital amps, but made a big mistake comparing it to a hk avr325. Well I will try to give an honest review without to much comparisions to the hk. I have since took the 25 back and ordered the sa xr45 . It has dual source capabilities,gold plated connectors and dts 24/96. The Panny has more than enough power to drive my,not so expensive ar hc5 speakers with plenty of sub output. I found myself actually turning the sub volume down with the Panny. In digital sources is where I think it really outdoes itself. The sounds are clear and precise without getting any ear fatigue after listening for long periods. There is no signal lose between tracks on cd or dvds when using digital cables. When I go from tv or sat. to dvd, I find myself not having to turn the volume up very much at all, sometimes I even have to turn it down. I am not much on reviews, and no I have not calibrated it with those disks, but I know what I hear. I will be more than happy to answer any questions if you aren't to rough on me. P.S. also it doesn't get very hot at all and I don't think the fan has kicked on yet.:b

 

[LanceJ]

Dale B: thanks for your thoughts on the Panasonic.

LJ

 

[Seth_L]

That's actually more of an operational quirk than a performance issue. Also, I thought there was another button on the remote that you could push to activate all 7 channels of the analog inputs after switching from a 2-channel source...?

Nope, only the left and right speakers will work when the multi channel input is activated (even from the remote) unless you had something that used those channel running prior to switching. That's not what I'd call an operational quirk.

 

[Lewis Besze]

Sure... On a 950, go from a 2 channel stereo source like the CD input and then switch to the multichannel input. You'll notice only the front 2 speakers work. You have to switch from something using DD or DPL2 or DTS into the multichannel input to get all 7 speakers to work.

Yes this is well known,but quiet old,I thought you had something new to add? I agree however that this is a bug,not a quirk,but it rearly affected me because of the way I set the 950 up.

 

[DarrylM]

Nope, only the left and right speakers will work when the multi channel input is activated (even from the remote) unless you had something that used those channel running prior to switching.

I wouldn't be using the analog inputs, since I'm not big into SACD or DVD-A, but I could certainly see where this would be annoying for those who did use them.

 

[Seth_L]

Yes this is well known,but quiet old,I thought you had something new to add? I agree however that this is a bug,not a quirk,but it rearly affected me because of the way I set the 950 up.

You'd think they'd have fixed it by now then...

 

[Craig_Kg]

Who knows, maybe Sony has something with their new ES line but I'll remain a skeptic for now. It surprises me that Sony would adopt digital amp technology in their audiophile line. It would make more sense to test it in their lower lines first.

They did. Their upper HTiB systems have used digital amplification for a while now. They seem to get good reviews for that sector (though it's hardly high end audio).