Topping B200 Monoblock Amplifier Review

[voodooless]

From those measurements you can compute the current as I=(P/Z)^0.5.

Or you’re lazy and have an AI do it:

 

[dcolak]

It depends on the load impedance. Also, Topping's specifications state that the measurements for the specifications were made using 220VAC/50Hz for the mains power. If you have different mains power, as we do in the U.S., the output power may be a little lower. In the first post in this thread Amir lists output power for different load impedances, presumably using 120VAC/60Hz. From those measurements you can compute the current as I=(P/Z)^0.5.

Regular Class AB 100W RMS @ 8ohm amps, like old NAD 2200 offer 60A peaks, being able to handle real speaker load and not collapse when the things get going.

How many amps peak can B200 provide?

Oh, I just saw it.. that's ridiculous, 7A?! You have to be very careful when choosing speakers for this amp, if you want to use anything but desktop speakers.

Pfffff...

Amir should start talking about current capability of the amps and how much is really needed to listen music loud with the proper bass and music peaks.

 

[dcolak]

NAD 3020 - Only 20 W/ch has peak current around 20 A depending on version. That means you can listen to your music with 5W average and when the kick drum hits or dynamic range starts expressing itself you still keep hearing everything uncompressed.

That punny 20W amp crushes B200 if you listen with more than 2-5W on average, not to mention any class AB 100W amp with proper current supply.

B200 might be ok for 2-5W average listening (let's say a 3m distance, 88-89dB/1w/1m speakers), everything over that, when that orchestra kicks in, sound will get compressed and not sound as good as it should.

Why are we not talking about the current capability of the amps and how much is needed if you listen at anything but low levels?

Is that why these are all called "desktop amps?" They assume you will not listen from more than 1m distance hence will not need to use a lot of power?

 

[terryforsythe]

Regular Class AB 100W RMS @ 8ohm amps, like old NAD 2200 offer 60A peaks, being able to handle real speaker load and not collapse when the things get going.

How many amps peak can B200 provide?

Oh, I just saw it.. that's ridiculous, 7A?! You have to be very careful when choosing speakers for this amp, if you want to use anything but desktop speakers.

Pfffff...

Amir should start talking about current capability of the amps and how much is really needed to listen music loud with the proper bass and music peaks.

I don't know where you got the 60A peak number from, but that is not anywhere near what Amir measured. At 4 ohms he measured, per CEA-2006/490A, 520.9W on one channel and 541.3W on the other channel, which are 11.4A and 11.6A, respectively.

NAD 2200 Vintage Amplifier Review

This is a review and detailed measurements of a refurbished and upgraded NAD 2200 stereo amplifier. It was bought by a member, sent to QuirkAudio to be fully updated and then loaned to me. The work that Peter has done is exemplary. The inside looks brand new! I have repaired hundreds of...

www.audiosciencereview.com

Nonethless, the NAD 2200 Is a good amplifier. If you can find one for a good price, get it.

 

[dcolak]

I don't know where you got the 60A peak number from, but that is not anywhere near what Amir measured. At 4 ohms he measured, per CEA-2006/490A, 520.9W on one channel and 541.3W on the other channel, which are 11.4A and 11.6A, respectively.

NAD 2200 Vintage Amplifier Review

This is a review and detailed measurements of a refurbished and upgraded NAD 2200 stereo amplifier. It was bought by a member, sent to QuirkAudio to be fully updated and then loaned to me. The work that Peter has done is exemplary. The inside looks brand new! I have repaired hundreds of...

www.audiosciencereview.com

Nonethless, the NAD 2200 Is a good amplifier. If you can find one for a good price, get it.

NAD 2200 Power Amplifier Review price specs - Hi-Fi Classic

www.hifi-classic.net

Is Amir measuring average or peak power? Dynamic transients need more than average power.

 

[terryforsythe]

NAD 2200 Power Amplifier Review price specs - Hi-Fi Classic

www.hifi-classic.net

From that article: "The output transistors of the NAD 2200 amplifier are high-powered, fast-switching devices capable of delivering some 60 amperes of peak current for brief periods." But, is the rest of the amplifier, including the power supply, capable of delivering 60A? Maybe, but there is no test data in the article confirming that is the case. Indeed, as noted, Amir's test results are not anywhere near 60A.

Let's assume that 60A is a true measurement. In order to do a proper comparison, you would need to determine the test conditions used to measure 60A, and then replicate those test conditions for the B200. Otherwise, you are making an apples to oranges comparison. The only apples to apples comparison we have are Amir's measurements, and there the differences are not anywhere near as high as you claim.

 

[terryforsythe]

NAD 2200 Power Amplifier Review price specs - Hi-Fi Classic

www.hifi-classic.net

Is Amir measuring average or peak power? Dynamic transients need more than average power.

 

[dcolak]

From that article: "The output transistors of the NAD 2200 amplifier are high-powered, fast-switching devices capable of delivering some 60 amperes of peak current for brief periods." But, is the rest of the amplifier, including the power supply, capable of delivering 60A? Maybe, but there is no test data in the article confirming that is the case. Indeed, as noted, Amir's test results are not anywhere near 60A.

Let's assume that 60A is a true measurement. In order to do a proper comparison, you would need to determine the test conditions used to measure 60A, and then replicate those test conditions for the B200. Otherwise, you are making an apples to oranges comparison. The only apples to apples comparison we have are Amir's measurements, and there the differences are not anywhere near as high as you claim.

You are missing the whole point.

Why are we not saying B200 is a desktop amp, not a real typical amp that can be used to listen to music from 3m distance at anything over 5W with speakers that are 89dB/1w/m or less?

People read "200W amp" and asume it's a powerful amp. No, not even close, with its 7 amperes.

I couldn't understand why all these desktop amps sounded so punny when I put them to work and now I get it... if you listen loud to dynamic music, they will compress the sound, it will sound flat.

 

[terryforsythe]

You are missing the whole point.

Why are we not saying B200 is a desktop amp, not a real typical amp that can be used to listen to music from 3m distance at anything over 5W with speakers that are 89dB/1w/m or less?

People read "200W amp" and asume it's a powerful amp. No, not even close, with its 7 amperes.

I couldn't understand why all these desktop amps sounded so punny when I put them to work and now I get it... if you listen loud to dynamic music, they will compress the sound, it will sound flat.

It depends on the particular use case. Let's go with your example of a 3m listening distance and 89dB/1W/1m speakers. Let's also assume the speakers are 4 ohm and that someone listens at a maximum of 80dB (which to me is a little too loud), with the speakers pulled out away from the front wall. Let's add 20dB for dynamic headroom, for a total of 100dB. The total power needed would be around 57W/channel. The B200 should have no issue with that use case:

Now, let's look at the same scenario, but with 8 ohm speakers. There, the power requirement is even lower, 28W/channel.

Here is a link to a spreadsheet I created where you can play with different scenarios:

Amplifier Power Requirement

docs.google.com

 

[dcolak]

You are assuming both speakers are playing mono signal, adding 3dB?

Only drums? Ok, but orchestral music is not like that. Jazz is not like that, music is not like that.

Maybe +1dB and that's it.

For a single speaker we're talking around 112W to get to 100dB at 3m.

We're also supposing speakers do not dip under 4 ohms, they are like resistors?

3 ohm dip would try to pull 16A peak/381W.

A lot of assumptions. And let's not even think about making a party in the house?

Desktop amps... lesson learned

Cool sheet! You even accounted for 2.83V vs ohms

 

[terryforsythe]

You are assuming both speakers are playing mono signal, adding 3dB?

Only drums? Ok, but orchestral music is not like that. Jazz is not like that, music is not like that.

Maybe +1dB and that's it.

That is incorrect. Test it for yourself. Put on music, set your balance control so that only one speaker is playing, and measure the SPL. Then, leaving the volume the same, turn the balance control back to center, and replay the same music passage. I just did it, and the SPL difference at my listening position was 3.7dB. Thus, using -3dB for loss from speaker separation in my spreadsheet actually is a bit conservative for my setup; it really is around -2.3dB. Your setup may be different, but not as bad as -5dB, which is the loss that would be needed to get down to a +1dB difference.

3 ohm dip would try to pull 16A peak/381W.

That is not correct. Remember there is room gain. Setting room gain to 0 in the spreadsheet is fine if you have the speakers setup in the middle of a field, but not if the speakers are in a typical room. In the example use case, if the speakers drop to 3 ohms, the total power would be roughly 76W/ch to reach 100dB dynamic peaks.

Regarding the actual amount of margin needed for dynamic peaks, a while back, I ran an experiment on that. Specifically, I compared LAFMax (maximum average SPL) and LZpeak (maximum SPL peaks). It was so loud as to be uncomfortable - I felt compelled to step out of the room during the test (note the LAE plot (aqua), which is the sound exposure level). In my test the highest dynamic peaks reached around 97.5dB. Here is a link to the post with the plots.

Topping B100 Amplifier Review

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...

www.audiosciencereview.com

I think we can agree that, for you and your listening preferences, the NAD 2200 is a good fit. That does not mean, though, that the B200 is not perfectly suitable for the listening preferences of other people. Every use case is different, and it is great to have a lot of different options.

 

[Dave TR3A]

Regular Class AB 100W RMS @ 8ohm amps, like old NAD 2200 offer 60A peaks, being able to handle real speaker load and not collapse when the things get going.

How many amps peak can B200 provide?

Oh, I just saw it.. that's ridiculous, 7A?! You have to be very careful when choosing speakers for this amp, if you want to use anything but desktop speakers.

Pfffff...

Amir should start talking about current capability of the amps and how much is really needed to listen music loud with the proper bass and music peaks.

Edited to show B200 specific values in addition to the example that had been requested. Changes/additions in red.

@dcolak This is nonsense. We're listening to music, not welding.

Extremely high amperage is unnecessary

The electrical theory is straightforward and has been shared in several posts. Class AB amps follow the same laws of physics as class D amps.

Certainly rated power specs for amps need to be taken with a grain of salt, and load impedance varies with frequency, but for an amp rated at 100W (which is what @dcolak cited as an example)

• driving an 8 ohm load, the amp would need to deliver 28.3 VRMS and 3.5A.
• for a 4 ohm load, it would need to deliver 20 VRMS and 5A.
• for a 2 ohm load, it would need to deliver 14V and 7A.

Any speaker demanding 60A from an amp would have to be an unrealistically low impedance. A 2 ohm load pulling 60A would see 120 VRMS --- that's 7200W!

Now let's look at the B200

Amir's measurements (see post #1) were 160W at 8 ohms, 210W at 4 ohms, and 84 watts at 2 ohms as per this chart:

Using those max. power values, the B200's electrical characteristics can be calculated using P=V^2/R and V=IR. Doing so yields:

• 160W at 8 ohms = 35.8 VRMS, 4.5A
• 210W at 4 ohms = 29.0 VRMS, 7.25A
• 84W at 2 ohms = 13.0 VRMS, 6.5A

What SPL can the B200 deliver?

For home audio listening, unless the speakers are extraordinarily inefficient, 100W would deliver ear-splitting SPL. Much home listening is done at 1W or less.

Although this formula pertains more to speakers than amps, let's run the numbers on the SPL that a B200 (or any amp rated for the same power output) would produce in the case you presented (listening at 3m distance with 88dB/1w/1m speakers).

Recall:

• while dB power is calculated as 10log(P2/P1), dB amplitude (such as SPL) is calculated as 20log(A2/A1).
• adding a second speaker increases SPL between +3 dB (for incoherent/out-of-phase sources) and +6 dB SPL (for coherent/in-phase sources)

88 dB SPL --- SPL produced from 1W
- 9.5 dB SPL --- SPL reduction at 3m distance (i.e., 20log(3/1) = -9.5 dB SPL)
78.5 dB SPL --- SPL at 3m when 1 speaker is driven with 1 watt

From information provided by Crown alongside one of their calculators, we find two formulae that can help us:
1) dBW = Lreq - Lsens + 20 * Log (D2/Dref) + HR
2) W = 10 to the power of (dBW / 10)

Where:
Lreq = required SPL at listener
Lsens = loudspeaker sensitivity (1W/1M)
D2 = loudspeaker-to-listener distance
Dref = reference distance
HR = desired amplifier headroom
dBW = ratio of power referenced to 1 watt
W = power required

Let's start by working backwards from 84W (max power of the B200 when driving 2 ohms, where the amperage requirement would be highest)
W = 10 to the power of (dBW / 10)
84 = 10^(dBW/10)
dBW = 19.2

With that we can approximate the SPL using
dBW = Lreq - Lsens + 20 * Log (D2/Dref) + HR
19.2 = Lreq - 88 + 20log(3/1)+0 (since we are not interested in amplifier headroom at this time, HR can be ignored)
19.2 = Lreq -88 + 9.5
19.2 = Lreq -78.5
Lreq = 97.7 dB SPL

The second speaker would add another 3 to 6 dB SPL, raising the volume at the listening position to over 100 dB SPL. That's the sort of volume one encounters in a nightclub. In fact, experts recommend no more than 15 minutes of exposure per week at that level without hearing protection.

If the speakers were 4 ohm (instead of the 2 ohms used above), the Lreq figure would be 101.7 dB SPL so that, with two speakers, one could expect close to 105 dB SPL at the listening position.

If the speakers were 8 ohm (instead of the 2 ohms used above), the Lreq figure would be 100.5 dB SPL so that, with two speakers, one could expect at least 104 dB SPL at the listening position.

Characterizing the B200 as a desktop amp is ridiculous.

 

[PristineSound]

This is nonsense.

For home audio listening, unless the speakers are extraordinarily inefficient, 100W would deliver ear-splitting SPL. Much home listening is done at 1W or less.

Extremely high amperage is unnecessary

The electrical theory is straightforward and has been shared in several posts. Class AB amps follow the same laws of physics as class D amps.

Certainly rated power specs for amps need to be taken with a grain of salt, and load impedance varies with frequency, but for an amp rated at 100W

• driving an 8 ohm load, the amp would need to deliver 28.3 VRMS and 3.5A.
• for a 4 ohm load, it would need to deliver 20 VRMS and 5A.
• for a 2 ohm load, it would need to deliver 14V and 7A.

Any speaker demanding 60A from an amp would have to be an unrealistically low impedance. A 2 ohm load pulling 60A would see 120 VRMS --- that's 7200W!

What SPL can the B200 deliver?

Let's run the numbers on the SPL that a B200 would produce in the case you presented (at 3m distance with 88dB/1w/1m speakers).

Recall:

• while dB power is calculated as 10log(P2/P1), dB amplitude (such as SPL) is calculated as 20log(A2/A1).
• adding a second speaker increases SPL between +3 dB (for incoherent/out-of-phase sources) and +6 dB SPL (for coherent/in-phase sources)

88 dB SPL --- SPL produced from 1W
- 9.5 dB SPL --- SPL reduction at 3m distance (i.e., 20log(3/1) = -9.5 dB SPL)
78.5 dB SPL --- SPL at 3m when 1 speaker is driven with 1 watt

From information provided by Crown alongside one of their calculators, we find two formulae that can help us:
1) dBW = Lreq - Lsens + 20 * Log (D2/Dref) + HR
2) W = 10 to the power of (dBW / 10)

Where:
Lreq = required SPL at listener
Lsens = loudspeaker sensitivity (1W/1M)
D2 = loudspeaker-to-listener distance
Dref = reference distance
HR = desired amplifier headroom
dBW = ratio of power referenced to 1 watt
W = power required

Let's start by working backwards from 84W (max power of the B200 when driving 2 ohms, where the amperage requirement would be highest)
W = 10 to the power of (dBW / 10)
84 = 10^(dBW/10)
dBW = 19.2

With that we can approximate the SPL using
dBW = Lreq - Lsens + 20 * Log (D2/Dref) + HR
19.2 = Lreq - 88 + 20log(3/1)+0 (since we are not interested in amplifier headroom at this time, HR can be ignored)
19.2 = Lreq -88 + 9.5
19.2 = Lreq -78.5
Lreq = 97.7 dB SPL

The second speaker would add another 3 to 6 dB SPL, raising the volume at the listening position to over 100 dB SPL. That's the sort of volume one encounters in a nightclub. In fact, experts recommend no more than 15 minutes of exposure per week at that level without hearing protection.

If the speakers were 8 ohm (instead of the 2 ohms used above), the Lreq figure would be 100.5 dB SPL so that, with two speakers, one could expect at least 104 dB SPL at the listening position.

Characterizing the B200 as "a desktop amp" is ridiculous.

But it ain't got no Hypex or Purifi power

And I still think this B200 ain't got nothing on Benchmark.

 

[Bleib]

Characterizing the B200 as "a desktop amp" is ridiculous.

This needs to be repeated more here on ASR. I've had people jumping out of their chairs with mere 2x15w connected to a pair of Ino Audio piP bookshelf speakers.

 

[dcolak]

The second speaker would add another 3 to 6 dB SPL, raising the volume at the listening position to over 100 dB SPL. That's the sort of volume one encounters in a nightclub. In fact, experts recommend no more than 15 minutes of exposure per week at that level without hearing protection.

If the speakers were 8 ohm (instead of the 2 ohms used above), the Lreq figure would be 100.5 dB SPL so that, with two speakers, one could expect at least 104 dB SPL at the listening position.

Characterizing the B200 as "a desktop amp" is ridiculous.

I'm afraid you are wrong. Check the excel terryforsythe created. Second speaker by no means adds 6dB. BTW, we are not talking about avg spl at all. Speakers are also no resistors and dip below 4 ohms easily.

Good luck with low current amps.

 

[dcolak]

I think we can agree that, for you and your listening preferences, the NAD 2200 is a good fit. That does not mean, though, that the B200 is not perfectly suitable for the listening preferences of other people. Every use case is different, and it is great to have a lot of different options.

Agreed, I won't be parting with LA 90 discretes, -10dB is max I can go with them before sound collapses, but it's usually loud and dynamic enough. For parties, I do have to switch to one of yamaha power amps, LA 90 simply runs out of steam.

 

[Dave TR3A]

I'm afraid you are wrong. Check the excel terryforsythe created. Second speaker by no means adds 6dB. BTW, we are not talking about avg spl at all. Speakers are also no resistors and dip below 4 ohms easily.

Good luck with low current amps.

You seem determined to twist data to suit your opinion.

Trying to justify your stance by an argument to authority (@terryforsythe 's spreadsheet) is specious. I have high regard for @terryforsythe but I think he favours my position more than yours. You need to prove your point. The amount of SPL contributed by a second speaker is not the same in all cases. The contribution typically ranges from around +3 dB to + 6dB. Heck, if you listened to only one frequency and were positioned at a null (i.e., completely out of phase), a second speaker could be detrimental.

In the calculations I showed, I used +3dB for the contribution of the second speaker, not +6dB.

Your grasp of electronics is tenuous. You attempt to sow confusion when you pretend that I (or others) are treating speakers as resistors. We talk about speaker impedance, not speaker resistance. A basic tenet of speaker impedance is that it varies with frequency. In my example, I used 2 ohm as the impedance value; it can't dip much below that before it's simply a short!

I've concluded that you're not interested in learning, or in facts, and are just trolling by promoting a foolish and indefensible idea.

 

[Dave TR3A]

But it ain't got no Hypex or Purifi power

And I still think this B200 ain't got nothing on Benchmark.

Hypex and Purifi are both excellent technologies. So are amps made by Benchmark. You'll get no argument from me on those points.

But if you want to position Hypex or Purifi-based amps (from Benchmark or others) with respect to other amps, such as the B200 ... I can't help thinking of a quote from W. Edwards Deming, "Without data, you're just another person with an opinion."

 

[-Matt-]

If @dcolak uses the wrong type of RCA to XLR adapter cable is it feasible that he could halve the power available to his speakers and thus get a wrong impression of the B200's capabilities?

 

[Deleted member 93733]

Maybe +1dB and that's it.

Can you show your calculations in assuming this?

For a single speaker we're talking around 112W to get to 100dB at 3m.

You assume a 6dB reduction per doubling of distance in a room. But you conveniently ignore the reverberant field. Why is this?

I am genuinely interested in the science and would like to understand whether it is bias or whether it is a lack of understanding that is forming these responses of yours.