stereo receivers

[dirtwarrior]

In the 80's I had a sansui 8080 receiver rated at 85 watts per chanel. Now I have a sony rated at 120 watts per chanel. The sansui will out play the sony in every way even though it is rated less wattage. How come?

[CoffeeFiend]

There's tons of possible reasons:

-one being stated in RMS (the old one), and the new one doing some fancy marketing tricks (could be PMPO or anything)

-even if that was 120w RMS, is that in a 8 ohm load? (I'd check the speaker's impedance too)

-are you using the same speakers for that test? (different speakers w/ diff sensitivity will give different volumes)

-some amps have more headroom than others (and some manufacturers are more optimistic/pessimistic than others too)

...

There shouldn't be that much of a difference between both amps regardless (like 1.5db extra or so, 10db being twice as loud). Speaker placement and distance can change volume more than that alone. And to really know for sure, you can't really trust your ears, you'd have to use some measurement device (unless the difference is so large that it's obvious)

Edited January 29, 2007 by crahak

[tommyp]

The first time I heard a Sony, I was absolutely disgusted. Nowadays, the audio manufacturer's are really pulling the strings with they way they spec them out. Audio equipment manufacturers forced people to believe that less THD is better. To get less THD, the design of the circuitry would need lots of feedback. This makes practically no distortion, but it also kills the character of the music. IMHO, the change came about in the mid 1980's.

Like dirtwarrior, I had an old 55 wpc receiver back in the early 80's. In the 90's I thought I did an upgrade when I bought a 100wpc model. I was extremely disappointed, especially since I was 500 bucks lighter! The past few years, I was busy designing and building my own audio amps, I made 3 so far just to say I could do it. I opted for tubes with my designs. The smallest of the amps is a 20 wpc amp. It may be hard to believe this, but the 20 watt amp outperforms the 100 watt amp (and the 55 wpc amp) hands down. It's louder, has character, and adds lots of realism (and it looks better too). The 70 wpc tube amp I made is an absolute masterpiece, but it weighs 70 lbs.

From a people's perception of music, it gets interesting. Any type of amplification distorts, there's no way around it. Transistors distort in odd order harmonics. Tubes distort in even order harmonics. People perceive even order distortion as a pleasant thing... which makes it sound warm. Bottom line, sometimes distortion isn't a bad thing, just as long as it's perceived nice.

[At0mic]

Yeah I bought a Pioneer stereo back in 1996. In the shop it said it was 100 Watts PMPO and the manual said it was 25 Watts RMS. I saw another shop selling it as 50 Watts MPO. Its just different ways of measuring the power outage.

Edited January 29, 2007 by At0mic

[prx984]

Exactly what others said here. It's over rating by the companies. My old Optimus STAV 3200 blows away home theater systems rated at over "1000" watts. It's all major BS if you ask me. The receiver I have is 100 watts RMS, and it can do it I'll tell you

Also, another thing, stuff isn't built the same as it used to be.

[ripken204]

well it all depends on how cheap you are. of coarse a 200$ receiver will suck.... although that is a good chunk of money, the only way to get good quality is to spend thousands. otherwise you will have to settle with what you get.

[prx984]

Ripken is right, you'll need to spend a decent amount of money. The receiver I have was 800 dollars new in '89 , speakers were 400 each

[ripken204]

and a decent receiver now is 800$, 1500$+ is when you just start to enter the good stuff.

[dirtwarrior]

I am going to get a system with a main amp and a preamp. Maybe a yamaha.

[Mordac85]

I disagree, you do not have to spend a lot of money to get a decent component if you understand what the specs are saying. Just b/c it costs a lot doesn't mean you're necessarily getting a better quality product.

PMPO is a hypothetical estimate of the peak output under perfect conditions and at 100% efficiency (i.e a marketing gimmick). It does not, in any way, relate to RMS. If the MFR doesn't state the power in RMS I'd stay away from that MFR and/or product. Anyone that thinks PMPO is a valid spec is full of crap and has no idea what they're talking about. If it's a salesman, go somewhere else or ask for the guru.

THD and freq response are possibly the next most critical specs. Remember, audio is an analog signal. IMHO, the tube amp, or a mag amp, is the way to go for a much better quality signal.

@tommyp

Keep up the good work , it'll pay off!