The year 2035: Super Street Topping Fighter PA5 III Turbo Alpha Deluxe Plus: SBPTBTBL Championship Edition*Sure thing, PA5 III++ will have the bypass
All we need is just a little patience...
*still with potted circuitry
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3e Audio A5 Stereo Amplifier Review
- Thread starter amirm
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*still with potted circuitry
OP
- Thread Starter
- #242
Please take caution in your posts with this kind of speculation. In front of me no less.
I used Volume bypass because this amplifier has very well thought out gain structure, obviating the need for the volume control. Use a front-end with its volume control (and remote if needed) and you are golden.
My time is limited. I can't test every variation to satisfy everyone.
OP
- Thread Starter
- #243
Pop and THD vs freq. added to review.
Thanks for this review @amirm . The 3e A5-A7 seems to check all boxes for me. Enough power, small, cheap, auto switch off, gain choice, no significant HF drop 10-20 kHz. Two of them can drive fronts and sub from my Marantz AVR, letting the AVR take care of the surrounds. Will probably buy two A7se.
obsessive9119
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Try and keep on topic (which isn't Topping ) and relevant please .It's what you say but not what you do (technically speaking).
But don't worry, I won't answer you anymore because you are very obviously too 'broad' in mind for me.
Have a good time
Roland68
Major Contributor
For something like this, I would recommend a wound adhesive based on ethyl-2-cyanoacrylate.
Reduces the pain surprisingly quickly and also allows you to continue working much faster.
Waxx
Major Contributor
Great to see that kind of performance for that price. It means that clean enough to no matter anymore is archivable for small budgets also now. If it's solid build and reliable (not like topping) we have a affordable device that is on level with lower end Ncore amps (or even better on some levels).
To be honest, my reference point is the available ASR reviews of Denon amplifiers, which typically show performance in the range of:Where did you get this number?
All I found was this:
S/N Ratio (Line, IHF-A) 98 dB At denon.com I could not find any performance specifications besides power.
Denon AVR-X1800H Review - Features, Specs, and Performance
Read our comprehensive review of the Denon AVR-X1800H. Discover its features, specs, performance, and why it's a top choice for audio enthusiasts.www.zkelectronics.com
Do you have a better source?
If it is correct, that is not SINAD but noise only and it is in relation to FS I suppose and not 5W and A-rated of course.
For 5W and without A filter this would be already quite different and then there is THD.
But the Denon is still an impressive peace of gear for the price. Just not what I am interested in.
SNR of the A5 is ≈120dB and that is without A-rating.
90 dB SINAD at ~5 watts
107 dB SINAD at full power (exact power output depends on the model).
Given that these amps usually operate with around 30 dB of gain, these are impressive numbers. It raises the question: is it really worth investing in an amplifier with marginally better specs if it offers no additional features beyond amplification? This is my main nitpick.
The amp itself is solid and well-built, but I find its target audience a bit unclear:
For purists, the specs might not be transparent enough.
For those looking for flexibility, there are better all-in-one solutions in the same price range.
For those needing more power, brands like Topping or Aiyima provide alternatives.
This product seems to sit awkwardly in the middle of these categories, which, honestly, leaves me a bit puzzled. I hope my perspective doesn’t come off as overly critical—just sharing my thoughts.
The 3e Audio A5 is simply a power amp, which happens to offer optional volume control (as has e.g. been common with pro audio power amps forever). It doesn't compete with integrated amplifiers, AVRs or all-in-one boxes at all.
So yes, this is an enthusiasts toy on a small scale. Does it mean it's too expensive? Everybody has to decide for themselves. I clearly do see the competition and I don't think the price is unreasonable by comparison.
There's an entire range of products (also containing A5se, A7se, A7 and A7 Mono) for different needs regarding current and power output. The A5 is just one iteration.
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Thanks! In my spreadsheet, I look at 15 kHz THD+N at 5 W, where the PA5 II is 1 dB ahead, but pick 0.5 W or 50 W and the A5 is 4 or 5 dB ahead.
What is more interesting is that the A5 has about 1.5 dB lower THD+N at 200 mW which is likely down to a more aggressive low pass filter on the output. This is in line with my observation that the ~38 kHz side bands in the two-tone IMD tests are more attenuated in the A5. The better 15 kHz THD+N performance in the broadband test of the A5 almost anywhere other than 5 W is probably owed to its steeper output filter. The classic 1 kHz distortion graph shows that A5 has about 8 dB higher high order harmonics in the 12 - 20 kHz range, likely due to its feedback loop running out of gain at a lower frequency.
In spite of this lower broadband noise, the A5 minimum distortion at 50+ W is still about 1.5 dB higher than for the PA5 II. Again, this is in line with the results of the two-tone and multi-tone IMD tests. It is interesting that this difference observed in the IMD tests at 5 W holds up at 50 W where the PA5 II with it lower power supply and presumably single TPA3251 is very close to its knee.
I think this confirms my hunch that the two amps (or at least the specimens tested) are very close, have comparable in-band noise but the PA5 II is slightly more linear. The greater headroom of the A5 does not translate into lower harmonic distortion near the clipping point of the weaker PA5 II.
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Just as a sanity check, I looked at archimago's measurements of the A5 and PA5 II Plus (same amp, higher current rating on the power brick).
I don't see those harmonics in the 12 - 20 kHz range being systematically higher in the A5. The distribution is just different, but this is what you often get even between the left and right channel of the TPA family. (Caveats 1) These graphs are at 1 W, but the 5 W graphs are about the same 2) I am not sure if archimago switched from E1DA ADC to ADCiso in between doing these measurements).
In the two tone graphs, which are at 1 W (and no 5 W graphs are provided), I see them as about the same around 19 kHz, and I see the same tendency of having more attenuation of the ~ 38 kHz products due to a steeper output filter.
So the specimens tested by archimago seem to be more equal in terms of (low power) distortion. I have yet to figure out a simple way to compare them at high power from his measurements. I have no explanation other than the lower test power as to why the lower frequency products at 2 - 7 kHz that are very evident in Amir's tests in the PA5 II and even more so in the A5 are simply not there in archimago's measurements of either amplifier.
I don't see those harmonics in the 12 - 20 kHz range being systematically higher in the A5. The distribution is just different, but this is what you often get even between the left and right channel of the TPA family. (Caveats 1) These graphs are at 1 W, but the 5 W graphs are about the same 2) I am not sure if archimago switched from E1DA ADC to ADCiso in between doing these measurements).
In the two tone graphs, which are at 1 W (and no 5 W graphs are provided), I see them as about the same around 19 kHz, and I see the same tendency of having more attenuation of the ~ 38 kHz products due to a steeper output filter.
So the specimens tested by archimago seem to be more equal in terms of (low power) distortion. I have yet to figure out a simple way to compare them at high power from his measurements. I have no explanation other than the lower test power as to why the lower frequency products at 2 - 7 kHz that are very evident in Amir's tests in the PA5 II and even more so in the A5 are simply not there in archimago's measurements of either amplifier.
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Where are you pulling these figures from, precisely? Looking at the reviews I'm not seeing anything over 90-ish dB SINAD at any power level for the 3800H and 4800H.
Also keep in mind that Amir has given the Denons a bit of a handicap here by using "Pure Direct" mode for the measurements. In practice, almost nobody will be using them that way since that disables all processing. When not in that mode, SINAD will decrease a fair amount.
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You have made your point ad nauseum. This is a power amp that has a volume control, which is probably not a very high quality volume control, but just don't friggin use it if you don't care for it. It already gives additional flexibility beyond those power amps that come with integrated volume control that you cannot even bypass.Like an extremely important crosstalk (unacceptable for a device that wants to be of a 'higher level') at the beginning of the potentiometer's travel...
... we better understand the interest of having added a bypass switch for it (LOL)
It could even be possible that the 5 Watts used for Amir's measurements are precisely within this range of use of the volume potentiometer, which forced Amir (and therefore also the users) to use the amplifier with the bypassed volume to measure it, but above all that he passes the 'test': to check...
I think this is perhaps the 12th post you have made on the same topic. Really makes one wonder what your ulterior motives are.
Thank you, amirm! Just what I am waiting for.
Measured output power is 122 W per channel into 4 Ohms with both channels driven = 244 W total. But the power supply is rated at 38 V and 5 A = 190 W. So either the PS has much more capacity than nominally stated, or this is a massive-overload but very-short-duration test relying on capacitance not sustained power.
Anyway, since this is a class D amp it would be good to learn its total efficiency, i.e. from the real power drawn from the wall receptacle to the actual power produced into a resistive load, plotted against the latter. IMO, all reviews of class D amps should include such a chart.
A side comment: Since it is clear that excellent performance can be achieved in amps using the TI class D chip with global feedback, why aren't any AVR manufacturers producing 9-, 11- or even 13-channel models with such amps and built-inSMPS? Surely, the cost and weight of a giant transformer (esp. a shielded toroidal one), a bank of massive rectifiers and caps, etc. in a linear PS could be beneficially eliminated. Let alone not burning ~70 W idle, as AVRs like Yamaha RX-A6A do.
Anyway, since this is a class D amp it would be good to learn its total efficiency, i.e. from the real power drawn from the wall receptacle to the actual power produced into a resistive load, plotted against the latter. IMO, all reviews of class D amps should include such a chart.
A side comment: Since it is clear that excellent performance can be achieved in amps using the TI class D chip with global feedback, why aren't any AVR manufacturers producing 9-, 11- or even 13-channel models with such amps and built-inSMPS? Surely, the cost and weight of a giant transformer (esp. a shielded toroidal one), a bank of massive rectifiers and caps, etc. in a linear PS could be beneficially eliminated. Let alone not burning ~70 W idle, as AVRs like Yamaha RX-A6A do.
According to @3eaudio the over current protection of the GaN SMPS units used kicks in above 7.5 A, even if the nominal current output is 5 A.
3e Audio TPA3251 TPA3255 Finished Amplifier with PFFB is coming!
Which code? The one posted to this forum or the one received through email for those who took the poll? Posted on the forum works.
audiosciencereview.com
I'm just citing, I don't judge.
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The answer is crest factor. The average power of music is much lower than during its peaks. The wattage of the transformer in a traditional AVR will also be much lower than its 9x 180 W or whatever advertised power.
SMPS and Class D amps are very efficient at high output, but not so much at low output. At one point, I compared the idle power consumption of a Hypex 400 W toroidal with rectifier and capacitor bank vs. a Hypex SMPS1200, and the toroidal won hands down.
The idle power consumption of stereo TPA325x amps is on the order of 5 - 10 W. The idle power consumption of a single channel Hypex module is more like 10 W.
I realized I had confused SINAD measurements with pure signal-to-noise ratio. SINAD is generally about 5 dB lower across the board for all AVRs. Interestingly, Denon AVRs seem to have a gain of around 26–29 dB, which is slightly lower than I expected.
That said, my main point still stands. Achieving 85 dB SINAD at 5 watts (worst case of all Denons) of the integrated amps in AVRs is just really good. This level of performance is great —essentially completely transparent for any listening purposes.
Also, the "pure direct" argument applies to DACs as well. Once you introduce preprocessing like EQ, loudness curves, or room correction, SINAD will likely drop by an amount proportional to the corrections applied (in dB). This is worth considering for anyone prioritizing transparency over processing features.
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