Sansui Stats

[Trw]

Is there a list/thread/sticky re stats?

I find Sansui stats very confusing! Sometimes listed at 1000hz sometimes 20-20khz sometimes 1 channel driven sometimes both

I.e i have an au-101 quoted as 15wpc and an au-505 quoted as 12wpc if you were looking at stats as a buying guide you would assume the 101 the more powerful i can assure you that it isn't ..or is it???

 

[Hyperion]

I don't think there is such a thread or list here on AK, chime in if you know different.

1KHz is the standard test frequency, and is often found where there are little or no other statistics. 20Hz-20Khz is the frequency range that a HiFi audio amplifier ought to be able to reproduce, and you'll often see figures of 'dB' quoted in association with this. This is a measure of the flatness of frequency response, and can also have power figures quoted alongside the frequency range. Any amplifier worth it's salt should be able to produce it's full rated power at 20Hz all the way up to 20Khz - and have a flat frequency response too. '1 Channel driven' power rating figures can be a measure of how robust the output stage and associated PSU are, these figures are almost always higher than the both channels driven figure, but are of little use in real world situations.

3wpc is a tiny power difference, note that to sound twice as loud you need to increase the power by 10 times! All of the above statistics and more are required to fully understand the characteristics of an amplifier, including crucially 'input sensitivity' and behaviour with a variety of speaker loads. The output stages of the AU-101 and AU-505 are slightly different - so may behave differently with the same speakers. The effect you note is widely discussed on here, and amplifiers sounding more 'gutsy' with seemingly lower power output spec's, why? - I don't know, other than a combination of the above effects. Sansui were always conservative with their power rating figures, I recently tested an AU-719 in this way, 90watts per channel spec' delivered a measured ~125watts into a dummy load at 1Khz (both channels driven).

 

[Skywatcher]

I will also add to what @Hyperion explained so well. With one channel driven, there is less of a load on the power supply so it can be measured at a bit higher output power level. When both channels are driven, the power supply is strained more thus unable to produce enough clean power to run both channels simultaneously at the same power level as a single channel. It's akin to your car going from 0 to 100MPH in 12.3 seconds with just you in it. But takes 13.4 seconds with a passenger the same weight as you. The engine (power supply) is strained a little more.
Using 1KHz as a "standard" of measure is a good "all around" and "fair" method to compare power output vs distortion.
The 20 - 20KHz notation is doing a full sweep of frequencies (human hearing range) and still meeting the published distortion specifications throughout the power band. Most, if not all amplifiers will put out more power, but the distortion also usually gets higher and beyond the specs published. And as Hyperion also stated, some very well built/designed amps can deliver well beyond the published specs, especially when rebuilt with modern, higher quality components than what were not available back then. So whenever you see the published specs, they are the minimum you can expect from a brand new, off the shelf unit.
Also, WPC output is merely a voltage measurement. It does not equate to decibel levels of sound pressure. That is a function of your speakers to convert that voltage into vibrations. The higher the efficiency of the speakers, the "louder" the sound level.

 

[Skywatcher]

Is there a list/thread/sticky re stats?

I find Sansui stats very confusing! Sometimes listed at 1000hz sometimes 20-20khz sometimes 1 channel driven sometimes both

I.e i have an au-101 quoted as 15wpc and an au-505 quoted as 12wpc if you were looking at stats as a buying guide you would assume the 101 the more powerful i can assure you that it isn't ..or is it???

The speakers will make the difference. Use the same speakers on both of those units, and they will be virtually equal in "loudness". 3 watts is very little difference. But on the other hand, if you used inefficient bookshelf speakers with a 5 inch woofer (say rated at 100w) on the 15 watter, and very efficient floor speakers (of equal quality) with 8 inch woofers (say rated for 50w) of on the 12 watter, the 12 watter will be much louder and better sounding. Why? There is more surface area to get the air molecules vibrating (sound pressure) and sent to your ears. Plus the larger cabinets will have better resonance for the lower frequencies making bass more pronounced. The bottom line is that watts isn't everything.

 

[Dswankey]

Is there a list/thread/sticky re stats?

I believe the word your looking for is Specs, if so Sansui manufactured a TON of various audio equipment over a long period of time. So to answer your question I'm pretty sure there is no thread, sticky or list.

Now if this something you really want to dive into I would say take the bull by the horns and do some compare and contrast research with regards to the pieces of equipment you're interested in.

I would start here and then if you wanted to go further here

https://www.classicaudio.com/value/san/index.html

http://akdatabase.com/AKview/thumbnails.php?album=28