Low Level Listening and Distortion

My experience with ganFet amps is that they sound boring at any volume level, let alone low volume setting. They just don’t “project” music like class A/AB amps do. I’ve only listened at length to one of these and I owned one and both were disappointing in comparison. Mids are a bit sucked out and bass is loose and not as textured in comparison. Tonality is worse for sure. Yes, they are clean up top, but it’s just boring as compared to my SS amp. They lack the “bite” of a good ss amp, or tube amp for that matter. My ss amp also had slightly less hiss with the volume cranked with no source material playing. I wanted to like these new class D amps, but nope.

Interesting. That’s pretty much what I’m hearing. Do you think my theory about distortion could be the issue? Distortion may cause/trick our minds into thinking depth, three dimensionality, wide soundstage, etc. so the lack of distortion of these newer class D amps leads to the opposite? I will say the AGD amps I heard didn’t sound like this but we know aural memory is rubbish so I could be and probably am wrong. I’ll have to try and hear the AGD again.

Most amplifiers reduce distortion as volume goes up.  Take a look at the distortion vs. output of a linear amp (figure 5) below.

Is it the job of a preamp to be sure the amp sounds the same at all levels or is this just impossible to make the sound that linear?

It's main job is to act as a buffer with variable gain.  The buffer part is that the source doesn't see a variable resistance.  Tubes often lack an output buffer though so the preamp itself may be subject to volume control variances.  The preamp can't compensate for problems in the amp though. 

The difference you are hearing may be due to speaker impedance / amp interaction.  It's possible one amp is responding more to the speaker load than the other.  If that depresses the midrange, at low volumes that may be helpful.

https://www.stereophile.com/content/luxman-l-509x-integrated-amplifier-measurements

Most amplifiers reduce distortion as volume goes up.

Mostly this. Your loudspeakers have way more distortion. There is however a volume level where your system will sound the most linear. That is where you should listen most of the time. 

In other words, a "clean" sounding amp (think stereotypical class D)

'Stereotypical class D'?? IME class D amps vary more in sound from one to another than all tube amps.

It sounds like you are talking about that 'first watt', which has to be musical for the amplifier to have a satisfying portrayal.

Thanks for the response @atmasphere. They may vary in sound but their reputation is a fairly sterile, clean sound as opposed to a tube amp which has a reputation for distortion, no? Ralph, you were who I was thinking of when I started this thread.  I believe in the past you said you like to be able to listen to music at louder volumes and it not sound too loud.  If I'm mistaken, please let me know.  Is it possible an amp that distorts at lower levels would be preferred to one that distorts at higher volume levels for someone that listens at 60 or 65 dB mostly? And, inversely, someone who listens at louder levels would dislike the same amp because once it's turned up it sounds "too loud"? Maybe I'm completely off base as my electrical and amplifier design knowledge is pretty close to zero.

interesting thread

when listening with intent (not background music etc etc) i am listening in the 75-85 db range (avg-peak) at my listening position, with speakers in a 11-12 ft triangle... i haven’t considered what the amps do at very low volumes

Another question is this.  Does anyone really enjoy music at "low level".  Other than for the sake of backgound noise, I have never been able to enjoy music without enough volume to let the sound open up.  Just saying.....

@bigtwin I enjoy music at low levels.  It's part of my weekend routine. Wake up early, go downstairs, throw on something I really want to hear and listen for a couple hours watching football/soccer on TV. I don't want to disturb anyone in the house so I have to keep it low. My Harbeth's are great at low level listening. My Devores seem to be more amp sensitive when it comes to under 70dB...hence part of the reason for my asking this question.  It makes sense to me logically that certain amps will sound thinner at low volumes, which is why loudness buttons used to exist (and still sort of do) but I've never heard an expert like Ralph's opinion on the subject of more pleasing distortion at low levels. Could an amp be made that specializes in sound up to 70 dB? I really have no idea.

@bigtwin

The enjoyment / volume is a function of quality of system… well, in general, there are exceptions. But, in general, the better the system, the less volume is required to be engaging. A few minutes ago I was captivated by a tune at volumes averaging 68 db. The high volume requirement is not required at al in great systems.

• +1 ghdprentice

1. @ghdprentice  What are saying?  Speak up.  I can't you over my loud system.  🤣  

All I know is that a lot of people choose the Sugden A21, A21se signature because it excels at low volume listening. It is a pure class A solid state amplifier. Mine sounds excellent at lower volumes, especially driving a 10 inch dual concentric driver in the Tannoys.

+1 ghdprentice

I listen a lot at very low levels when my wife is asleep. But the ambient noise level drops at night also. However, it is a very good test of a system as to how engaging it is at low levels - more linear, wide bandwidth systems do well here. Conversely, in my experience, if you need to play a system loud to make it sound good, that reflects badly on it.

+2 ghdprentice

That has been my experience. The better my system got, the less I needed to crank it to get the same sensation and dynamic contrasts. Even at low levels now, the system still has a good soundstage, excellent presence and inner detail, and is still very pleasant. At low levels the bass output isn’t as strong, but still sounds full. Distortion levels are likely not the whole answer.

I had an Ayre AX-5 using it as an amp with their KX-R (non-Twenty version) and Salk Encore speakers that excelled at low level listening like nothing I've heard before. I don't think distortion came into play at all but the "blackness" of the Ayre really helped. The Salk's are a more "modern" sound than the Devore's. Maybe that helps delineate the sound from the quiet passages better. Sort of an added sharpness to the bass that more traditional speakers don't necessarily do that allows for more quiet space between notes so to speak. 🤷‍♂️

good systems still sound engaging at low levels

I believe in the past you said you like to be able to listen to music at louder volumes and it not sound too loud.

@bhvf That's not exactly right. What I've often said is that its the mark of a good system that it can play at high volume without sounding loud. IOW you can't tell that its playing loud until you find you have to shout to be heard by someone sitting next to you.

But it should also be engaging at low volume- for that matter at any volume. So you need a good first watt too!

Of course the amp has to have its ducks in a row, so does the preamp; there should be good vibration control for the CDP and turntable, so the the front end of your system is unassailable by the volume in the room.

I am a fan of Salk Song3 Encores.  I was most impressed at the RMAF.  

@bigtwin

“Speak up. I can’t you over my loud system.” 👍😊👏

@atmasphere  I agree, really good systems can also play loud and not be fatiguing; blackness in between the sounds, low distortion… so not adding sound pressure to your eardrums that are non-music. I believe this also drops the SPL… not having all the extra noice in there. 

@ghdprentice,

Just curious, what do you consider low, normal and high levels? For me, low is below 50-55 db. Normal is 55-75 db and high starts at 75ish.

Thanks.

Just now, listening average mid 60s db. Normally mid to high 70s.

Quite engaging making it difficult to write this post. Imaging and soundstage are right on. And, in a way, drawing me into the music more than louder.

Class D GANfet AGD Audions. “Complete” sound with very low, inaudible distortion. Think the lower volume is suited to the current content-C, S & N.

Thanks for this thread. Maybe the lower volume will continue to engage. It is more relaxing.

I listen to music at just about every level as I'm a believer that all music has a proper level which goes beyond anyone's taste in volume.  A small amount of that is dictated by the recording itself as opposed to the actual music.

Try blasting Simon & Garfunkel some time, it doesn't work for me.  Nor does listening to DSOTM at anything but full blast.

I'm listening to Billie Eilish - Happier Than Ever - Not My Responsibility and the SPL was 63-69 which is kinda loud but correct.

What say you?

Regards,

barts 

Let it play the next track as well, they lead into each other.  You're welcome.

Regards,

barts

I also failed to mention that the noise floor in my listening room is 18db.

Honestly can't imagine hearing leaf blowers.

Regards,

barts

@curiousjim

To me low is 55 - 65 ish, normal is around 65 - 75 loud 80 - 90db.

This has changed as my systems have evolved. In the 70’s and 80’s I used to seek out opportunities to hear loud systems… I remember going to a high end store which had Klipschorn’s and enough power to crank around 110db. What was obvious in retrospect… the SPL meter did not move a lot… meaning the background noise was very high (was deafening)… the high frequency hash and noise floor. I still can remember the background hash… at the time I had no idea what it was. That was a sizable amount of the sound pressure. In retrospect some of the worse sound I have heard.

Now with my current and contemporary systems the background noise and hash is just gone. What is driving the SPL meter is the actual music only. A lot of the perception of loud is difference between the noise floor and the notes.

“This has changed as my systems have evolved. In the 70’s and 80’s I used to seek out opportunities to hear loud systems… I remember going to a high end store which had Klipschorn’s and enough power to crank around 110db.”
 

The JBL Century 100’s - DQ-10’s with Apmpzilla - Son of Ampzilla and modded Hafler amps cranked up to 11!  What were the big Bozak speakers from mid/late seventies?

Those were the days.

I remember the JBL Century as well. Sex, drugs, and rock and roll… yes, good sound quality… no.

I had JBL Century 100 s. Looks like many also had them in the early ‘70s.

Miss those college days and cranking the JBLs!

@mglik 

👍. it was fun! 

we all hear differently, sometimes domestic conditions require us to listen at lower volumes

some folks listen real loud (usually dealing with some level of hearing loss) - once i had a fellow come over to ’audition’ my spatial m3s at the time, really nice guy, zen healer body worker type, very educated but man, he listened sooooooo loud... i thought my head was going to explode, i literally had to leave the room

to me, when i think about low level listening, a lot of it is about the fletcher munson effect and how that is dealt with - to me, good sound has a richness and texture and warmth to it, within which details can be heard, that can be hard to accomplish at low levels

there is something about a sweet first watt, but to me it is alot about noise floor, and very low distortion throughout the range, through volume levels, whether the whole chain (and every item in it) can hold it together when spl’s rise - be it in the electrical signal or in the final transducer (cone breakup, crossover resonances, etc etc)

yes i agree, very very good systems often play loud effortlessly, without strain, without a sense of the sound being extruded, or shot at you like from a water cannon... as a defining trait

@jjss49 Great post! "to me, good sound has a richness and texture and warmth to it, within which details can be heard". That says so much to me. Often times we can find richness, texture and warmth but at the expense of detail, or we find detail at the expense of richness, texture and warmth. Low levels make getting both out of your setup difficult. What makes a system great to me is walking the line between the two at all volumes.  I've heard systems that sound much better at low volumes than high and vice versa.  I guess that's why I started the thread. One could buy 2 amps and switch them out depending on listening level preferences at the time,  or find an amp that can do both...which is not easy to say the least. In my experience this is what better, and most of the time, more expensive, amps get you.