Topping B100 Amplifier Review

[Sokel]

What settings did you use to show the LA and LZ measurements?

Using the RTA in REW, I measured RMS and Peak, sampling 3 songs. This about as loud as I typically listen, measured at about 2m:

View attachment 393444

Open REW,choose the "SPL meter" tab and then choose SPL,choose weighting,fast or slow and Logger.
At the window which will open press the upper right red dot,same as the RTA window.

 

[Sokel]

What settings did you use to show the LA and LZ measurements?

Using the RTA in REW, I measured RMS and Peak, sampling 3 songs. This about as loud as I typically listen, measured at about 2m:

View attachment 393444

Also,as a test use a bass-heavy song and first measure it with (A) weighting and then with (C) weighting WITHOUT changing level and observe the big difference as the later captures lows too.

 

[EddNog]

Also,as a test use a bass-heavy song and first measure it with (A) weighting and then with (C) weighting WITHOUT changing level and observe the big difference as the later captures lows too.

Should I be re-checking my 1hr avg and peak using A weighting instead of C to try and exclude my subwoofer?

-Ed

 

[Sokel]

Should I be re-checking my 1hr avg and peak using A weighting instead of C to try and exclude my subwoofer?

-Ed

You could do that too,yes.
But (C) is more representative in my opinion as it includes most of what you hear.

 

[terryforsythe]

Also,as a test use a bass-heavy song and first measure it with (A) weighting and then with (C) weighting WITHOUT changing level and observe the big difference as the later captures lows too.

I ran the test before I saw this post. The second and fourth songs are bass heavy. I played these on my office speakers (KEF LS60) louder than I normally would listen, and measured at my listening position (2m). I ran four complete songs. The songs I ran are:

1. "Upcoast" by Brett Staska
2. "Wildfires" by Sault
3. "Love Story" by Indila
4. "You and Me" by MEUTE

I just realized REW's screen capture did not include the legend. I re-opened REW and did a screen capture of it. Hopefully it did not change the colors:

 

[EddNog]

You could do that too,yes.
But (C) is more representative in my opinion as it includes most of what you hear.

Right, that’s why the first time I did this, I went C-weighted.

-Ed

 

[Sokel]

I ran the test before I saw this post. The second and fourth songs are bass heavy. I played these on my office speakers (KEF LS60) at my listening position (2m), louder than I normally would listen. I ran four complete songs. The songs I ran are:

1. "County Line" by Brett Staska
2. "Wildfires" by Sault
3. "Love Story" by Indila
4. "You and Me" by MEUTE

View attachment 393459

Seems about right for (A) weighting,nice recorded songs played back without clipping is about there,15-20dB between max and peak.
Heavily compressed ones on the other hand...

 

[terryforsythe]

Seems about right for (A) weighting,nice recorded songs played back without clipping is about there,15-20dB between max and peak.
Heavily compressed ones on the other hand...

I just picked songs I like from my playlist.

The first two are compressed for sure. The third and fourth songs don't sound compressed to me, but perhaps they are. Take a listen to "You and Me" by MEUTE and see what you think.

 

[Sokel]

I just picked songs I like from my playlist.

The first two are compressed for sure. The third and fourth songs don't sound compressed to me, but perhaps they are. Take a listen to "You and Me" by MEUTE and see what you think.

I hope I found the right one,there's a gazillion of covers,etc.
Sounds good,nothing to complain about.

 

[kyuu]

It's true that people generally need less power than they think, assuming their speakers are of average sensitivity or better and they are in a typical home setting. However, if the choice is between an amp with, say, 80dB SINAD and 160W and one with 120dB SINAD and 60W, I'd choose the former (except maybe for near field listening with very sensitive speakers to avoid hiss). The additional SINAD will be inaudible under pretty much all circumstances. The extra headroom, on the other hand, might come in handy for the occasional dynamic peak, even if most listening barely breaks into the double-digit wattage range.

Of course, if we could get both plenty of power and vanishingly low noise/distortion on the cheap, that'd be swell too.

 

[terryforsythe]

I hope I found the right one,there's a gazillion of covers,etc.

On Tidal I enter the artist name, MEUTE, and only one version of that song comes up.

 

[SMen]

Just to put things right,in not only about SPL.
A kick drum can go to 125dB,yes,with the pedal far enough (18-20cm) from the drumhead but the important thing here is its dynamic range which can go up to a staggering 80dB.
And,acoustic guitar is not at 75dB,is more closer to 90dB.
(you don't even want to know what a sax can do)

I had a source (article) for that and meant to quote it. Maybe it was classical guitar ... but I think you are clarifying and adding value to my point about natural sound volumes. And about the importance of the compression in the recording itself, and conversely where the recording does have peaks for headroom in the amp.
These all have an influence in where we might 'set that volume dial' I think.

A good saxophonist gets just over 95 dB out of a saxophone. I once measured it in the studio when there were a few problems with a recording.

Interesting about the saxophone.

I think this is why I still enjoy my records! It's in the nature of the compression. I listen to a lot of alto saxophone.

 

[Old_School_Brad]

I had a source (article) for that and meant to quote it. Maybe it was classical guitar ... but I think you are clarifying and adding value to my point. And about the importance of the compression in the recording itself, and conversely headroom in the amp for where the recording does have peaks.
These all have an influence in where we might 'set that volume dial' I think.


Interesting about the saxophone. I think this is why I still enjoy my records! It's in the nature of the compression.

Maybe this:

Acoustical Characteristics of Musical Instruments

www.dpamicrophones.com

 

[SMen]

Maybe this:

Acoustical Characteristics of Musical Instruments

www.dpamicrophones.com

Thank you - that's excellent ... so many peak in the 90's and above...

Duly bookmarked!

 

[DanielT]

There is a market for the amplifier that tops Amir's SINAD list. Of course, manufacturers, if they see an opportunity to make money from it, will try to reach the number 1 position. The plus that I suspect that there is a competition between different manufacturers that spurs to be in place number 1.

For my own part, SINAD around 70-80 is okay. Had I had better low-distortion speakers, maybe amp SINAD around 90 then to be on the absolutely safe distortion headroom side.

Having said that, I think it is GOOD with this SINAD competition because it encourages, motivates manufacturers to move forward in technological development. It benefits everyone EVEN if you don't need a 120 SINAD amplifier. It will probably,I'm guessing,"spill" over, so to speak, so that in the future there will be affordable 150 watt amplifiers with SINAD of around 100. At a lower price than today, that is.
Should Texas Instruments also create new amp chips, this could of course also facilitate the creation of an even better price-performance ratio.

Anyway. Fascinating development. How is that possible? I am not an EE so I only understand a little of what is said in the thread below, but it is interesting:

Class B amplifier with SINAD of 120, how is that possible?

I thought that class B based amplifiers advantage were a lot of power in combination with the disadvantage of high distortion. To solve the negative aspect class A design was integrated, creating the classic combination: Class AB amplifier. BUT why bother with this AB combination if it can be...

audiosciencereview.com

 

[Old_School_Brad]

Thank you - that's excellent ... so many peak in the 90's and above...

Duly bookmarked!

Yes. The dynamics in music, if you want them and have speakers that can handle them, demands power. Simple as that.
Add EQ/room correction to that and you can double, triple or quadruple that number.

Without going into calculation examples, I'll just say this: There's a reason that powered monitors such as Genelec uses powerful amplification for even small drivers.

 

[torgeirs]

I think the calculation following calculation is interesting for acoustic music and listening to same loudness as the original instrument.
First a reference: https://www.neumann.com/fr-fr/knowl.../what-is-self-noise-or-equivalent-noise-level

Neumann studio microphone TLM 103

Cardioid characteristic✔️Large diaphragm capsule ✔️pristine, clear sound✔️Extremely low self-noise✔️ Capsule design derived from the legendary U 87 A✔️

www.neumann.com

So let's take that 7 dBA selfnoise mic and a 100 dB/1w 4 ohm speaker.
What is the selfnoise of the speaker/amp when amp has 0dB gain and 0.3 uV noise?

So selfnoise of speaker/amp is 43 dB lower than the mic. (some shortcuts made)

So how many uV noise will the mic make if 7 dBA noise from mic will generate 7 dBA noise from that speaker at 1m

Sensitivity at 1 kHz into 1 kohm	23 mV/Pa = –32.5 dBV ± 1 dB

So 1 pascal acoustic noise generates -33dBV electric noise on mic output. (some shortcuts made)
7dBA Noise from mic is -33dBV - (94 dBV - 7dBV) = -120 dBV or 1 uV noise.

So why must not the amp have a little less noise than that?
Because that noise will be amplified in the mic amp.
To have the same SPL into mic generating same SPL out of speaker, we need 33 dB GAIN. And it is not in amp. It is in the the mic amp.
Then that 1 uV noise from mic is 33 uV noise when the signal comes to the amp.
So source has 33uV noise. amp/speaker has 0,3uV noise.

 

[antcollinet]

I've heard massive amounts of feedback (often used to get these kind of low numbers in AB amplifiers)

What you’ve heard there is audiophile mythology.

 

[mlsstl]

Maybe this:

Acoustical Characteristics of Musical Instruments

www.dpamicrophones.com

Would point out that those dB figures appear to be measured immediately adjacent to the instrument itself so would not reflect what one would hear in an audience seat however many feet away. And it would also not reflect what appears on most recordings after being mixed and processed. It's biggest point might be that the musicians playing those instruments might want to consider hearing protection.

 

[Roland68]

It's biggest point might be that the musicians playing those instruments might want to consider hearing protection.

Most musicians wear IEMs, which already have protection integrated.