I am going over 1001 schematics for what I want to try next. The amp I just finished up is about 5 watts per channel and it seems about half as loud as my "100 watts per channel 🙄" 5 channel surround system.
Is there a factor for tube watts vs. solid state watts? I am thinking there has to be some load of bull in rating the solid state gear, like maybe peak on one channel if all the others have no signal or some scam like that.
For a room in a house 25 watts per channel of tube watts would seem to me to be much more than adequate if 5 is loud. Maybe 8-10 is fine for the next one?
Is there a factor for tube watts vs. solid state watts? I am thinking there has to be some load of bull in rating the solid state gear, like maybe peak on one channel if all the others have no signal or some scam like that.
For a room in a house 25 watts per channel of tube watts would seem to me to be much more than adequate if 5 is loud. Maybe 8-10 is fine for the next one?
That means typically a 100W amplifier is twice as loud as a 10W amplifier, and a 10W amp is twice as loud as a 1W amplifier. This applies to tubes and transistors.
Half as loud as 100 W. is 10 W. As Jon stated, it's logarithmic.
A watt is a watt, regardless of the technology used to generate it. What is different between tubes and SS is clipping behavior. SS hard clips against the PSU rail(s), which can be very destructive to tweeters. Tubes saturate and "compress", prior to hard clipping.
A watt is a watt, regardless of the technology used to generate it. What is different between tubes and SS is clipping behavior. SS hard clips against the PSU rail(s), which can be very destructive to tweeters. Tubes saturate and "compress", prior to hard clipping.
Watt ratings of solid state amplifiers are bogus. A common rating of 100 wpc means, in Class AB, that amplifier itself dissipates 100 W of heat, or 500 W if it is 5 channel. Inside such amp, there is a flimsy heat sink barely capable of 20 W total.
The same is true for speakers. Is it possible that 100 W of heat can be continuously dissipated inside a closed box? No way, it will be on fire in 15 minutes.
The same is true for speakers. Is it possible that 100 W of heat can be continuously dissipated inside a closed box? No way, it will be on fire in 15 minutes.
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Oh yes, if we're talking about PMPO ratings - Peak Music Power Output. Total marde.
I've even seen the "adhesive upgrade" - a 100W sticker over the 80W sticker. All using a 12V 1A wall wart! Remarkable speakers, indeed!
I've even seen the "adhesive upgrade" - a 100W sticker over the 80W sticker. All using a 12V 1A wall wart! Remarkable speakers, indeed!
I agree with your estimate.
Back in the late 60s I used a mono 10W push-pull EL84 amp and a pair of efficient speakers to provide a 'record session' in a public hall full of excited young kids.
The system was plenty loud! 😎
Most domestic listening is done at a level of around 1W, so 10 - 25W would give you ample headroom when using speakers of average sensitivity (86 - 87 dB/W/m).
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That's right.
My 17W per channel tube amp easily coasts along at normal livingroom listening levels.. perhaps putting out 1 to 3 watts to each Advent floorstanding air-suspension speaker.
At full volume, my neighbors next door would be irritated.
Yet, some people insist on monster amps with hundreds of watts....
They must be deaf, live in a large stadium, or drink the koolaid.
Obviously, you take what they said with plenty of salt, but Feldman and Hirsch tested SS HIFI amps RMS power O/P into big, honking, resistors. Also, there was a FTC mandated pretest heating requirement. Now, what some of those amps did into a reactive loudspeaker load is another story.
If you read the fine print carefully, the specifications for a lot of home theater equipment show how puny their true power O/P is. Very nasty sounding power integrated circuits, as opposed to discrete transistors, also make for p_ss poor performance.
If you read the fine print carefully, the specifications for a lot of home theater equipment show how puny their true power O/P is. Very nasty sounding power integrated circuits, as opposed to discrete transistors, also make for p_ss poor performance.
I own a very good sounding 250 WPC tube/FET hybrid amp. The power capability is there so the amp "never" clips, not to wreck an entire city block. Remember, far more speakers have been damaged by clipping amps than by excessive power.
"Better to be looking at it than looking for it." Keith Fenner
Small watts
I have some DIY with ecl82 se, el84se triode wired, and about 1,5 watts Claas A. With my Klipsch speakers (RF15 or RP-160M), and the volume knob at "12" o`clock, music fills my livingroom, pretty loud! My friends do not believe me, when I tell them that the amp gives us about 1,5 watts!
I have some DIY with ecl82 se, el84se triode wired, and about 1,5 watts Claas A. With my Klipsch speakers (RF15 or RP-160M), and the volume knob at "12" o`clock, music fills my livingroom, pretty loud! My friends do not believe me, when I tell them that the amp gives us about 1,5 watts!
It would appear that your statement is debatable:
Does “Underpowering” Damage Loudspeakers? | Thomas Cornish Consulting | TJ Cornish
https://www.epanorama.net/sff/Audio...and_its_Effect_on_Loudspeaker_Reliability.pdf
Not mentioned so far is that the nature of how an amplifier clips and how it recovers from clipping. It can make as much diiferences as real differences in power.
It has been over time turned into a "tube power vrs SS power” thing, but has little to do with it. Historically tube amps have clipped gracefully and SS amps, particualrly early ones went to crap when they clipped.
But it is more a design thing.
Both the NAD 3020 and Nelson Pass ACA are both SS amps that sound way more powerful than one would think because they pass the “how does it clip” test very well. My 3.2w PP #L94 class A amp as well.
dave
It has been over time turned into a "tube power vrs SS power” thing, but has little to do with it. Historically tube amps have clipped gracefully and SS amps, particualrly early ones went to crap when they clipped.
But it is more a design thing.
Both the NAD 3020 and Nelson Pass ACA are both SS amps that sound way more powerful than one would think because they pass the “how does it clip” test very well. My 3.2w PP #L94 class A amp as well.
dave
A frequently clipping SS power amp does damage tweeters. Apply Fourier's Theorem to the FUGLY clipped waveform.
They do. Just ask all those poor Advent tweeters that expired due to poor 1970s SS receivers being clipped.
dave
dave
Dave is correct about NAD's 3020, a little engine that definitely could. IIRC, Hirsch measured something in excess of 6 dB. dynamic headroom into 4 Ω. While definitely not sustainable, 80 W. instantaneous pulses is anything but shabby. Hirsch, Feldman, and TAS all "drooled" over NAD's 3020. 
Here's a rigorous examination of clipping from the University of St. Andrews which may be to your liking.
However, do note the realistic, real-world conclusions at the foot of the pages.
Amplifier clipping and tweeter damage
Creating HF power by clipping
Tweeter damage by compression
The NAD 7080 90wpch receiver I bought new in '78 blew up an also new pair of B&W DM7s I bought along with it. I was ogling the new Boothroyd Stuart Meridiam 105 mono 100wpch kit but didn't want to lay out 3 times the cost. The NAD had zero, nada, nyet headroom; consequently burned up the coils in the woofers only, not the tweeters. I never had the volume more than 4.5. I had it for one month, promptly returned it and traded for the Meridians with 7db headroom! That 90 wpch really wasn't very loud with the DM7s. They got fixed under warranty but I didn't even take them back; someone there wanted them so I sold them, got a pair of KEF 105.2, and SHOOK THE HOUSE! Those Meridians are awesome to say the least. Very surprising for their small footprint. Sq is second to none even now. I never saw the red clipping indicator on the Kefs light up unless I cranked it just to see if they're functional. I have never heard a better sounding amp ss or tube. They were NAIM's direct competition preferred by many.
The reason tweeters blow when your amp clips is because the HF component of the signal is still being amplified even though the woofer is flapping out of gas. You think ALL frequencies are being clipped but they're not and you end up overpowering the tweeter in an effort to get more bass.
The NAD 3020 marked a change in NAD’s design philosophy. We saw a few of that old series, but not many. They had been discontinued by the time we got into NAD.
dave
dave