Topping B100 Amplifier Review

[testp]

you can technically a/b test two devices close to level-matched, if you double the blind tests amount and make sure half of the time one is louder, then the other is louder, random order. person giving the value, should not know which one of course

 

[antcollinet]

you can technically a/b test two devices close to level-matched, if you double the blind tests amount and make sure half of the time one is louder, then the other is louder, random order. person giving the value, should not know which one of course

But then you would have to ensure the amount by which each is louder would have to be carefully matched - or you would be introducing a bias in the test.

Easier by far to make sure the devices are closely matched (to within 1%) in the first place.

 

[testp]

But then you would have to ensure the amount by which each is louder would have to be carefully matched - or you would be introducing a bias in the test.

Easier by far to make sure the devices are closely matched (to within 1%) in the first place.

well if the problem is not having a proper "level matched setup", then tester makes one test set with as "level matched" as possible, the one that was worst (more than marginally), can be set slightly louder/quieter (maybe pref. is quieter instead, so both ways..), that way the worst gets it chance and the result would rebut level differences as argument for the first test, the result concludes that, there was a difference heard in the first test. <- these tests has to be blind for the tester.

just saying..there are options around "properly level matched" argument for regular ppl with just a mic (not perfect but close enough..)

[EDIT] just realized, louder/quieter test cannot both be included for assesment (bc one of them would favor the winner), so worst performing of the two would be the control, to evaluate if one still prefers the winner of "level matched" test, ...it is doable, just 3x vs. 1x times the test and blind of course.

[EDIT2] just realized , the argument isn't which one is better at all (that subjective), the question should be: is there a difference, so in "level matched" setup, tester should succesfully distinguish 7/10 of the two, then do louder/quieter tests, pick the worst performing test as control: if the worst performing test got 7/10, it should say, tester was able to distinguish two devices and they were sounding different in "level matched" setup. just food for thought, and testing can be fun.

 

[antcollinet]

well if the problem is not having a proper "level matched setup", then tester makes one test set with as "level matched" as possible, the one that was worst (more than marginally), can be set slightly louder/quieter (maybe pref. is quieter instead, so both ways..), that way the worst gets it chance and the result would rebut level differences as argument for the first test, the result concludes that, there was a difference heard in the first test. <- these tests has to be blind for the tester.

just saying..there are options around "properly level matched" argument for regular ppl with just a mic (not perfect but close enough..)

[EDIT] just realized, louder/quieter test cannot both be included for assesment (bc one of them would favor the winner), so worst performing of the two would be the control, to evaluate if one still prefers the winner of "level matched" test, ...it is doable, just 3x vs. 1x times the test and blind of course.

[EDIT2] just realized , the argument isn't which one is better at all (that subjective), the question should be: is there a difference, so in "level matched" setup, tester should succesfully distinguish 7/10 of the two, then do louder/quieter tests, pick the worst performing test as control: if the worst performing test got 7/10, it should say, tester was able to distinguish two devices and they were sounding different in "level matched" setup. just food for thought, and testing can be fun.

First - you need 8 out of ten for any sort of significance - and even then there is a 5% chance of getting that by guess work.

And there is no way of setting up a valid test without accurate level matching. Mis matched levels simply mean you there is no way of telling if the result was influenced by the level mismatch.

 

[testp]

First - you need 8 out of ten for any sort of significance - and even then there is a 5% chance of getting that by guess work.

And there is no way of setting up a valid test without accurate level matching. Mis matched levels simply mean you there is no way of telling if the result was influenced by the level mismatch.

if someone heard a difference and they used a mic approach to "level match", why not try by incrementing up/down by .2db, then by 0.4db, it will either get "properly" level matched and difference is not heard (proving setup was not level matched) or it stays different,
i will always be proponent for yes|or approaches bdw.

 

[FERCSA]

After one year of service one of my B100s just died. Lovely xmas present.. I thought

There was zero reaction to touching the power button. Turned out there was a cold joint -actually three- located at the touch sensor panel.

After a quick soldering session at 2am my system works again.

I just leave it here maybe one day it'll be useful for someone.

 

[Panelhead]

GTK.
I read there have been a couple running production changes to the B100. Think these were to address failure rate. The serial numbers are A-735x for my pair.
But since getting a dac with trigger I see the light. Have not touched touch sensor since. My system is upstairs in a loft. Being able to turn on and off dac and amps downstairs is huge. More than trying the ROHM chip in a D200 or having 15v output and PEM in an E50 II. Now an E50 II with trigger would be on backorder.
I used to wonder why people felt trigger is an important feature.

 

[magreen]

Thank you for taking the time and effort to read through our experience and for the sound (ha ha) and usefull advise!

Ad.1:
The SU8 has 40 steps, but accuracy is indeed about 0,1/0,2 as the level was not always constant but switching between 75.0/75.1 during readout the dB app of my phone.

If I understand correctly (DVM =Digital Volt Meter? Most probably not Doctor of Veterinary Medicine ;-) ) I can better measure the voltage on the speaker connectors instead of the dB's at the speaker driver itself? I can do that.

Ad.2:
Actually we are also comparing DAC's here, so indeed not that controlled.With the better DAC of the Ultra on the PA5.

If I want to use the B100 in my setup (surround & stereo) I need to use it through the SU-8 as the Ultra has no balanced output but does have digital out. For a speedy change I used the PA5 on RCA.
When I find time I'll redo the test with same connectors

Ad.3: 5 trials or so, didn't count them exactly. Each person. Every single trial was in favor of the B100 without doubts. With a 3(.125) % chance on guessing right...would you put your money on that? ;-)
When we redo it with same connection for both amps (either RCA or XLR), I'll keep the exact score.

Also have to see measurements of connections since that could also make a difference in sound.

Ad 4: very true! Maybe use a curtain in front or an eye patch for the testperson!

I am really looking forward to your retesting of this matchup. I am in the market for a replacement of a high quality amp for classical music, and these two amps are quite high in the running.

 

[Jazigo]

I am really looking forward to your retesting of this matchup. I am in the market for a replacement of a high quality amp for classical music, and these two amps are quite high in the running.

Maybe this thread is of interest to you: https://www.audiosciencereview.com/...onse-enough-to-determine-sound-quality.68183/

Me and @NoFuzz agrees on the differences, but we simply can't prove it yet, but I intend to do some more measurements during my holidays.

 

[magreen]

Maybe this thread is of interest to you: https://www.audiosciencereview.com/...onse-enough-to-determine-sound-quality.68183/

Me and @NoFuzz agrees on the differences, but we simply can't prove it yet, but I intend to do some more measurements during my holidays.

Thanks. Looking forward to seeing your further measurements.

 

[HakanC]

But since getting a dac with trigger I see the light. Have not touched touch sensor since.

Same for me
I have my two B100 connected to a WiiM Ultra and the remote trigger out from the Ultra takes care of on and off the B100s
And I have not touched the power "buttons" on the B100 since

 

[Bluedog]

DO THE CHINESE NOT UNDERSTAND AIR CONVECTION AT ALL? Look at the holes on the B100, look at the fin placement on the B200 radiator? What the hell?

 

[Panelhead]

DO THE CHINESE NOT UNDERSTAND AIR CONVECTION AT ALL? Look at the holes on the B100, look at the fin placement on the B200 radiator? What the hell?

I think the Class B B100 does not need more. The Class AB B200 must not either.
That said I used to use several pairs of Altec 1570B that were Class B. They generated a lot of heat.

 

[Nzama]

No, not perfect then. Far from it. A microphone (or any measurement of in room SPL) is insufficiently accurate for level matching for a blind test. You have no idea if your perceptions came from the audio quality of the device, or from slightly mismatched levels.

What I dont get about your point is that if this is true it shall help randomly amps while it seems in many cases according to reports the b100 can ve preferred.

 

[oleg87]

What I dont get about your point is that if this is true it shall help randomly amps while it seems in many cases according to reports the b100 can ve preferred.

If you had no idea which one you’re listening to, you’d likely prefer the louder one. Otherwise it’s still filtering through the rest of your brain.

 

[Sokel]

After one year of service one of my B100s just died. Lovely xmas present.. I thought

There was zero reaction to touching the power button. Turned out there was a cold joint -actually three- located at the touch sensor panel.
View attachment 499507
After a quick soldering session at 2am my system works again.
View attachment 499508
I just leave it here maybe one day it'll be useful for someone.

The big caps under the chip and the one next the little linear PSU could use a little extra solder as well, it seems they have the bare minimum.
(and I would check all joints while being there, three of them is no accident, is just haste to product more units as it seems)

 

[antcollinet]

DO THE CHINESE NOT UNDERSTAND AIR CONVECTION AT ALL? Look at the holes on the B100, look at the fin placement on the B200 radiator? What the hell?

Everything in engineering is a compromise. The question is - do those thermal designs work well enough as they are. If they do - no need to worry further.

 

[Bluedog]

Everything in engineering is a compromise. The question is - do those thermal designs work well enough as they are. If they do - no need to worry further.

Classic power amplifiers never compromised on the orientation of the heatsink fins. Horizontal fins indicate forced cooling. And even more so, no one even thought about making the top surface without holes.

 

[BeeKay]

Classic power amplifiers never compromised on the orientation of the heatsink fins. Horizontal fins indicate forced cooling. And even more so, no one even thought about making the top surface without holes.

Those classic power amps you mention often were class A. Different animal in terms of heat dissipation demand. That’s likely comparing apples and oranges.

 

[NTK]

Topping plays the number game of SINAD, for which the only reward is in the bragging right of "engineering excellence" by sequeezing out the highest last but totally insignificant digits in SINAD numbers versus their peers. It is therefore, IMHO, absolutely fair to criticize them for their lack of engineering common sense in their thermal design (i.e. displaying severe ignorance of good thermal design practices).