Paul Klipsch was right - What the world needs is a good 5 watt amplifier

The INT-25 doesn't have "poorly rated power". It's a high current amp that's relatively low wattage due to being Class A. No shock at all it drove those speakers.

The Topping PA5 ($349) is more powerful than the Pass amp and has lower distortion. Why pay 10X the money for the Pass?  

Jason, is that from real world A/B testing, or opinion? You get what you pay for. The Toppings does not get outstanding reviews, where the Pass Lbs stuff is legendary. I would love to save money on equipment rather than a name, if you have REAL proof of this, please tell.?

A good 5 watt amp is still a 5 watt amp. There are many systems where that will not be enough power. 

@Mr Bourne,
You honestly think the 300 buck Chinese amp sounds as good as a Pass Class A ? ? Not even close. 

Jason has all the measurements to prove it, so get off your high horse mister.

obviously anybody who pays more than $340 for a 30W amp is ill advised...

Jason has all the measurements to prove it

The measurements were outstanding but that doesn’t tell us how it sounds and to be fair he only listened to it on a single 400 buck speaker so maybe not the last word in definition. Correction, he bought it new for 160 bucks. 

you a bit slow on the caffeine uptake today Russ ?

My old 6 ohm salk songtowers were 88db and also dipped momentarily into 3ohm territory. A Primaluna Dialogue Premium @ 35w was way more power than I needed. Never ever got into trouble driving those speakers hard.

Truth is 88db is not so tough to drive for most hight quality amps making 25+ watts. However, 86db may be another story. 

the point of the video is to show that the Pass with its poorly rated power (25wpc) can drive even demanding speakers to insanely loud levels without any sound degradation. 

Paul Klipsch was right - What the world needs is a good 5 watt amplifier

I'm missing something.  Where's that confounded bridge (segue)?

@noske I really don't understand your question

I really don't understand your question

That's OK.  In the absence of an explanation, the title of the thread and the body of it bear little resemblance.   A non sequitur.

There is no 5 wpc amplifier used in the test or in any subsequent discussion.

Paul Klipsch made that remark decades back when he was using a Brook 2A3 PP tube amp. Certainly 5 watts is enough to get orchestral SPL peak levels from a pair of Klipschorns!

@mofojo : It's all in the circuit design! The PA5 uses quite advanced design - making it rate right up there with the Benchmark AHB2 amp - at 10 times the price!

What is the point in comparing a class A S.S. amp to a SET 5 watt 2A3 amplifier? It isnt the power it is current vs voltage.

No Jason it isnt just in the circuit design. If you want to spend less and think you get more that is fine, but please be quiet when people (presumably) who listen are speaking.

My Sugden A21 is only 30 watts driving speakers rated at 89 db. Plenty loud! Class A is amazing. 

Sensitivity isn't the issue as much as impedance curve. The Pass can handle it because those speakers are it's raison d'etre. A 300B SET won't do here.

Having said that I used 845SET's with Merlin VSM-MM, around 90db with pretty benign impedance curve. I doubt 300B could handle. I once tried for kicks 2a3 monoblocks I had at the time on the Merlins, nice transistor radio sound.

The problem with 5wpc amp is so few speakers allow for it. I'm not even sure my Klipschorns would be happy with less than the 8wpc my 300B amps provide. I was considering 2a3 or 45 amp until I saw a number of less than stellar reviews of the pairing. Khorns  with shallow slope crossovers do have a bit of impedance concern, steep slope and drop down to aprox. 3ohms at 100hz.

I'm not even sure my Klipschorns would be happy with less than the 8wpc my 300B amps provide.

I know some people like low power amps (single digit output) but even at lower volumes higher power amps can work better. I use 25wpc tube mono blocks on my main system and it's enough for me. I have used low power chip amps but they fall far short. I think some are satisfied with what they hear but I assume they my be ignoring the benefits of higher power or in the case of a quality tube amp, they sound more powerful than their low power rating suggests. 

@jasonbourne52 

The Topping PA5 ($349) is more powerful than the Pass amp and has lower distortion. Why pay 10X the money for the Pass?  

I've great appreciation for topping devices and with great respect I think the PA5 wouldn't be able to drive those speakers above 80dbs before it will start clipping. Don't rely on laboratory measurements as the music is much more complex and dynamic and it is not 1 KHz sine wave

I cannot name this individual ( it is not me )....He owns top of the line CJ gear / Avantgarde horns....Based on my very positive recent talks with him about a chip amp I have been listening to, he went ahead and purchased the PA5, AND LOVES IT. He also has gone passive, and is loving his new sound. His words : From warm and colorful, to clean, precise, immediate, snappy, detailed, fast........more truthful to the recording ( whatever that means ). Enjoy. I am loving my chip amp. 

This is so appropriate for me right now. A couple weeks ago I built a $150 K-12G tube amplifier of 8w/ch......I built it just for fun as I like building stuff and the price was right. I had zero intention of ever using it seriously. But then I connected it to my KEF LS50 Metas and Oh My Lord, does it sound great! At up to 80dB in my 12X24X8 heavily damped room it never strains. The sound quality is simply magnificent and I find myself listening to it for hours. I also have a Pass Labs First Watt F5v2 (50w/ch) and a VTA ST120 Dynaco Clone (60 w/ch) and a Yamaha M45 (125w/ch)....And recently I’m favoring the K-12G.....Read all about my adventure with the little amp here... www.rvbprecision.com

The Topping PA5 ($349) is more powerful than the Pass amp and has lower distortion. Why pay 10X the money for the Pass?  

Measures Good,,,,Sound?...Not so much....I can

t tell you how many components I bought in the last two "Covid Years" that had great reviews/measurements by "Audio Science Reviews" that I had to return because they were unlistenable. I have an Topping MX3 that I use in a sunroom and in that environment it is fine, but no way is it to be compared to my $150 tube amplifier kit (8w/ch) or my Pass First Watt F5v2 (50w/ch).......ASR has really panned the Pass Kit "Amp Camp Amp" (ACA). Called it everything but a total POS. And the specs they posted are horrible. But I've heard quite a few of these little amps and they sound fantastic. Extremely "musical" and do not sound like computer sound cards like most higher power, lower price Class D Chinese amplifiers. Don't get me wrong, I'm a real fan of Class D. This past week I built an ICE Power class D 200w/ch kit and for $300 it is amazing. Not tubes or First Watt, but very, very close......Read all about THAT adventure here... www.rvbprecision.com

I cant tell you how many components I bought in the last two "Covid Years" that had great reviews/measurements by "Audio Science Reviews" that I had to return because they were unlistenable.

IMO too little attention is paid to distortion spectra when amps are measured; IME its one of the more important things to study in an amp. The real problem here isn't the measurements, its what is defined as 'good'.

@celestial__sound 

I've great appreciation for topping devices and with great respect I think the PA5 wouldn't be able to drive those speakers above 80dbs before it will start clipping. Don't rely on laboratory measurements as the music is much more complex and dynamic and it is not 1 KHz sine wave

Measurements don't tell you how a piece of gear is going to sound, no matter what brand, especially not measurements from REW. The music playback in the video didn't sound too great, even considering it's compressed Youtube footage.

The music playback in the video didn’t sound too great, even considering it’s compressed Youtube footage

@divertiti The video is recorded with my 70$ smartphone (huawei). Don’t you think Wilson Chronosonic driven by D’Agoustino Monoblocks will sound the same on my phone? Don’t you?

Please don’t waste our time with comments like this ... PLEASE

I recently sold locally a Pass ACA amp I had purchased 2nd hand. With my listening habits being what they are, it did not adequately power my Lascalas. 

@celestial__sound 

The video is recorded with my 70$ smartphone (huawei). Don’t you think Wilson Chronosonic driven by D’Agoustino Monoblocks will sound the same on my phone? Don’t you?

Please don’t waste our time with comments like this ... PLEASE

You are so close to self awareness it's actually painful. You posted a video measuring an amplifier using REW and an SPL read out making claims about distortion and sound quality, on a $70 cell phone non-the-less. "waste our time" is exactly the right phrase to describe this thread.

105db or higher for 5 watt to sound sufficently good enough at decent volume level and even then it depends on the room and seating distance. These amps struggle with bass.

Personally i would not touch flea watt amps unless my speaker is 110db or higher in sensitivity and room is optimised whilst at the same time im not sitting to far away.

Who is listening at 100db and higher?

I mostly listen at 64-85db, occasionally hitting 90db which is too loud for for more than a few minutes!

@phantom_av at what temperature range do you listen?

I didn't know speakers rated at 110dB or greater existed.  What am I missing out on?

industrial grade deafness methinks…

speaker sensitivty buffoons not listening SPL :-)

100 dBs SPL is painfully loud. I never listen to those levels as well. The video is just a demonstration and it lasts no more than a minute.  The room is 34 square meters and the microphone is placed at 2m distance from each speaker. 

@divertiti Ignored.

i prob hit about 90db splt levels in my room which is heavily treated. I was talking about speaker sensitivity and small amps, you need very sensitive speakers if you using anything under a few watts.

Yep, I agree

Measurements don't tell you how a piece of gear is going to sound, no matter what brand, especially not measurements from REW

Sure they do- but for that simple reason you rarely see them , and I've found that many people don't understand what the measurements are saying. The things to look at are distortion vs frequency (must not rise across the band or the equipment will sound bright), distortion spectra at 1 watt and at all frequencies, distortion spectra at -6dB of full power, and IMD (not CCIR version), the latter at -6dB of full power.

Interpreting  this information properly will tell you exactly how the amplifier will sound.

100 dBs SPL is painfully loud.

If this is the case it points to a distortion problem causing the pain, unless you have hyperacusis.

There are plenty to go around.   No that's not what the world needs more of.

100 dBs SPL is painfully loud.

If this is the case it points to a distortion problem causing the pain, unless you have hyperacusis.

Painfully loud is metaphoric saying for very loud, otherwise the thread may had "My amp distorts at high volume " title.

And, no my ears weren't bleeding either :)  

My peak levels approach 100db + and it does not hurt me in any way. My ears check out fine, as I have annual check ups. This is such a very important aspect to music reproduction for me. That is my story......

My peak levels approach 100db + and it does not hurt me in any way. My ears check out fine, as I have annual check ups. This is such a very important aspect to music reproduction for me.

+1 My point exactly.

This is such a bizarre phenomenon that some refuse to look at any aspect of sound other than peak SPL capability. This is most likely the result of decades of TAS and Strereophile culture where the reviewers set the "highest standard" by gear that they blast at unlistenable levels. In case a system is not capable to win that silly feat, it's not real high end.

Sadly, people (for not knowing it better) try to jump on this bandwagon in hopes of finding high fidelity. True, there are some of us who do crave excessively loud music (regardless the cause: joy or damaged hearing).  But these are far and few in between. If you are one of these, I salute you.

However, when you are like 98% of the population, excessively loud sounds will give you more pain and discomfort than pleasure. The decades old figure of "102dB/m" as gold standard for peak output is there so that when we listen at 75-80dB peak volume there's still 20dB headroom for the transients, and you stay in the goldilocks zone the entire time, and never run out of headroom.

Before you decide to pull the ultra-loud trigger there are a few things you need to know:

1., Even a few minutes of 100+dB SPL exposure can cause permanent hearing damage. (Largely from the distortion components in the sound, which, at that level, completely overload and damage our auditory system.) The damage is also the function of exposure time: 1h at 90dB will damage your ears just as well. Look up the NIOSH guidelines.)

2. If it's louder the brain thinks it "sounds better". (The "wedding band" effect.... they play louder to hide poor technique.) Train your ears to recognize sound quality, and do not take the instant gratification reflex for granted - all it will do is ruin your hearing well ahead of time. Once hearing is gone, there's no return. Our hearing is a One way ticket. Treat it with respect, as it is your greatest asset as an audiophile! 

3. Gear that is optimized to play silly loud often plays poorly at lower volumes. So, you have no choice but to play louder and louder to "upgrade".... and form the firm belief that the only solution for sonic improvement is stepping the volume up.

4. Sure, rock concerts are loud... if that's what you want, live volume rock concert at home, then by all means go for >100dB sustained SPL. Here in the US police has the authority to confiscate your stereo system if you regularly subject your neighborhood to such abuse. Concerts have special licenses to play that loud. Did you obtain one from your major's office?  Or, did you install movie-theater grade soundproofing to prevent excessive noise complaints? (Even in that case the next neighbors will still call the cops, but the noise complaint will be below the level where they confiscate your rig.)

Back to volume requirements.... My SET is capable of putting out 1.2W peak into my 102dB/Wm efficient speakers. I can play any concert (Pink Floyd, Rush) where I have the feel, the "vibe", the rush that I am at a live concert.I do not need any higher volume, and nobody who heard it said they want it any louder...

And yes, sure, I was at live Aerosmith concert, and that was much louder than 100dB or so, but that was a painful experience and I would have enjoyed it much more had they played at a volume that does not require industrial ear protection. (It took a week for my hearing to return after that concert.... lesson learned!)

I can listen to my system at full volume, for hours, without a trace of fatigue. I call that sonic bliss. I basically have a limitless pass to an unending season with Vivaldi, Handel, Bach, Beethoven, Mozart, Mahler, Holst, Rameau... with the same level of experience I feel at the concert hall. (Which I frequent frequently.) I agree with the thread-starter - all we need is a few clean watts. And with super efficient  (100dB/Wm+) speakers, 1W is enough.

Cheers;

PS: @noske  there are 110+dB/Wm speakers.... actually, there's one that's not DIY/unique build: Altec VOTT A1x... will not fit in any living room though. A pair of them is as heavy as 4 cars, and you could house a family inside each cabinet. ;  You are not missing out on much unless you have a concert hall or an IMAX theater size room to house them. ; ). Even the baby-brother, the 109dB/Wm Altec VOTT A4 is still so big you have to knock down a wall to bring it into the room... and even then a single cabinet will occupy most of the space.... you need an auditorium for them as well ;

Funny thing which i can't seem to explain is why this phenomenon occurs on the Atma-Sphere amplifiers and pre-amps. Iv not really experienced this on other audio gear iv tried tested personally or at friends.

If I Measure the room SPL Level at a friend's house 95db to 100db on peaks, It gets rather uncomfortable. This applies to SET and SS.

However on the Atma Sphere gear, 90db in-room spl measurements don't actually feel loud at all, even 95db don't really feel uncomfortable. If anything you kinda get the urge to keep cranking the volume up.

FWIW front row center at an orchestral concert can easily be over 100dB on peaks.

There are a lot of things that can cause harshness in a system when you try to run the volume at realistic levels.

Early side wall reflections are interpreted by the ear as harshness.

Higher ordered harmonics are interpreted as harshness.

Resonances excited by vibration in a turntable or vacuum tubes (microphonics) are interpreted by harshness.

Slap echoes in the room are interpreted as harshness.

Even if you don't play at +100dB levels, getting a handle on these things will result in a more musical relaxed presentation in the room even if 85dB is your maximum volume.

Of course you want your amp to have a good first watt!

I have Polk Lsim707, they say their 88db,but I have read reviews there more like 85 db....well I had a lot of amps with 200 to 250 wpc to drive them...My Chinese made Cayin A50TP MK II with 16w Triode 35 w Ultra drives them with no problems what so ever...I have a big room 25 ×35 Cathedral ceiling  ,and I can play them Loud.....

Hi All,

You all are much more knowledgeable than me, so I have a couple of questions if I may.

I bit the bullet and bought a pair of Klipsch Forte iv's in order to try a pair of high efficiency speakers. Listened to Cornwalls four or five times but felt, for me, the bass was better with the Forte's.

Played the Forte's with my McCormack DNA-500 amp, which is great with my Theil CS5i's, but not so much with the Forte's. 

Switched out to my old CJ LP66S tube amp and the sound greatly improved. In my space, 60 wpc is much more than enough. I think 30 wpc could be too much.

First question: does it make sense that the DNA-500 probably would not sound good with horns? Why?

Second Question: I recall reading somewhere that horns generally do not like amplifiers that use a lot of negative feedback. Is this generally true? Why?

Just trying to lay the groundwork to try a lower power tube amp or maybe Pass/First Watt?

Thanks for listening,

Dsper