New Fosi Audio V3 Mono vs Topping PA5 II vs Topping PA7 (inc. 'Plus' versions)...and Aiyima A70

[Yorkshire Mouth]

Someone in the new Fosi thread said a new thread would appear to compare models, so here it is.

Links to Amir's reviews of the three:

Fosi Audio V3 Mono
Topping PA5 II
Topping PA7
Aiyima A70

Prices are V3 Mono $260 (pair), PA5 II Plus $290, PA7 Plus $550, Aiyima A70 $220.

Does the V3 match or beat the PA5 II Plus? Can it even approach the PA7 Plus?

I'm going to go to each of those three review and check the specs, then edit this first post.

Meanwhile, chat away.

THD+N: Fosi 100dB, PA5 II 105dB, PA7 Plus 102.5dB. Not a lot in it, I think. ADDITION: A70 95dB.

Signal to Noise Ratio at 5W & full power: Fosi 103dB/120dB, PA5 II 107dB/120.5dB, PA7 Plus 105dB/122dB. Again, very close. ADDITION: A70 100db/116dB.

Frequency response and load dependency: All four marked as inaudible, except the Fosi ay 8ohm. However, it's still within 0.5dB right up to c.15kHz - I suspect most of us can't hear 15-20kHz, and for those who can its not dominant. YMMV, as they say.

Distortion: Fosi below between -130dB and -110dB up to 5kHz, then up to -90dB at 20kHz. PA5 II -130dB to -120dB up to 5kHz, then rising to -110dB at 20kHz. PA7 Plus around -120dB right up to 5kHz, then up to c.105dB at 20kHz. ADDITION: A70 -120dB to -105dB up to 5kHz, then up to -10dB at 20kHz.

Distortion-free range: Fosi 11 bits, PA5 II 15 bits, PA7 Plus ???. ADDITION: A70 13.3bits.

Maximum Power at 1% THD into 4 ohms/Peak Power: Fosi 244W/242W, PA5 II 120W/120W, PA7 Plus 236W235W. ADDITION: A70 178W/185W.

Other areas: I'm going to leave to others to decipher, as I feel others will do a better job of it than me. Just one more:

Bragging rights: If you own the Fosi you can say you own monoblocks. Seriously, when I was starting off in the wotld of hi-fi, only rich executives owned separate pre and power amps, as opposed to an integrated amp, let alone two monoblocks! Also, if one of your Fosis breaks down, it only costs $130 for a new one to replace that, with both Toppings you have to replace the whole thing.

But just initially, the Fosi does very well, considering it's the cheapest. PA5 vs PA7: The PA7 appears to be very similar to the PA5, except it has far more power. PA5 vs Fosi: The PA5 is a little better than the Fosi distortion-wise, but the Fosi has PA7 levels of power. PA7 vs Fosi: Similar power, the PA7 is cleaner, but costs more than twice as much.

Well, that's my initial reading, I may have made errors, for which I humbly apologise (that sounds a lot nicer than E&OE).

Over to you.

 

[staticV3]

Does the V3 match or beat the PA5 II Plus?

2x V3 Mono is slightly worse than PA5 II Plus in all aspects but output power.

At 4Ω, it can play 20% louder than the Topping (1% THD+N).

If your speakers need it, then that 20% difference in loudness will 100% be more audible that all of the V3 Mono's slight step-downs in noise, distortion, and frequency response combined, resulting in a superior listening experience.

If you know that you'll never need that extra 20% loudness, might as well choose the Topping for its superior performance, All-in-One package, built-in volume control, and 12V trigger.

 

[Yorkshire Mouth]

Don't forget the AIYIMA A70.

It measures slightly worse than Fosi in 1khz tests but measures better at higher frequencies as evidenced in multi-tone and 19+20khz tests. I also prefer the Aiyima's frequency response.

Apparently Aiyima improved the pop-on noise in production units compared to the unit Amir reviewed, while Fosi improved their FR.

I am getting both to compare but will probably keep the Fosi for better design and more available power.

Thanks for including the link - saves me the job.

I won't transcribe all the measurements over, but I'll have a look.

Best wishes.

 

[Yorkshire Mouth]

Don't forget the AIYIMA A70.

It measures slightly worse than Fosi in 1khz tests but measures better at higher frequencies as evidenced in multi-tone and 19+20khz tests. I also prefer the Aiyima's frequency response.

Apparently Aiyima improved the pop-on noise in production units compared to the unit Amir reviewed, while Fosi improved their FR.

I am getting both to compare but will probably keep the Fosi for better design and more available power.

Oh, go on, I've done it.

Anyone else asks for another amp they can do it themselves.

 

[Guddu]

Oh, go on, I've done it.

Anyone else asks for another amp they can do it themselves.

 

[mike70]

reliability? ... i haven't heard much about fossi and aiyima ... but i do hear many complains about topping.

and this aspect is VERY important for me.

 

[Abstracted]

reliability? ... i haven't heard much about fossi and aiyima ... but i do hear many complains about topping.

and this aspect is VERY important for me.

This is the main reason why I'm considering exchanging my open box PA7 (non-plus for $269) for 2 Fosi's.

Although, I have seen very few complaints from PA7, and PA5 II, owners regarding reliability.

 

[mike70]

This is the main reason why I'm considering exchanging my open box PA7 (non-plus for $269) for 2 Fosi's.

Although, I have seen very few complaints from PA7, and PA5 II, owners regarding reliability.

what about the temperature in your PA7? because the past problems are regarding thermal management

 

[kibs]

I'd wanted to get the fosi V3 stereo but have opted to wait for the version with PFFB. Will be interesting to compare Mono with the stereo version.
Is channel separation that significant irl that monoblocks would have an advantage ? Or what would be significantly different about monoblocks?
Also the Pa7 plus seems to be in a different price bracket, doesn't fit here.

 

[Yorkshire Mouth]

Just as a general point, what it most likely to make an amp (any amp) fail, other than immediate and gross misuse?

If you have an amp, and you use it well within its limits, are you less likely for it to give up the ghost than one regularly pushed to (and beyond) the limit?

 

[MaxwellsEq]

Just as a general point, what it most likely to make an amp (any amp) fail, other than immediate and gross misuse?

If you have an amp, and you use it well within its limits, are you less likely for it to give up the ghost than one regularly pushed to (and beyond) the limit?

That will depend on the tolerance and heat extraction of those parts of the design which are under strain when heavily loaded. This usually includes PSU components and output devices. If the manufacturer significantly over-specs the components such that they are not driven beyond their tolerance and are not overheated, then heavy use should be not have a significant impact on longevity.

In practice, picking component tolerance is a cost/benefit task and so heavy loading may reduce lifetime. Meanwhile, poor heat extraction will definitely have a longevity consequence.

 

[Yorkshire Mouth]

That will depend on the tolerance and heat extraction of those parts of the design which are under strain when heavily loaded. This usually includes PSU components and output devices. If the manufacturer significantly over-specs the components such that they are not driven beyond their tolerance and are not overheated, then heavy use should be not have a significant impact on longevity.

In practice, picking component tolerance is a cost/benefit task and so heavy loading may reduce lifetime. Meanwhile, poor heat extraction will definitely have a longevity consequence.

Cheers, that covers most of it.

But specifically, if you use it lightly, are you less likely to see it fail? Obviously, if it’s overspecced, that’s going to help. But if the components are ‘just enough’ will someone who doesn’t use it too often, and not drive it too hard, be less likely to see a failure?

Many thanks.

 

[Sokel]

Cheers, that covers most of it.

But specifically, if you use it lightly, are you less likely to see it fail? Obviously, if it’s overspecced, that’s going to help. But if the components are ‘just enough’ will someone who doesn’t use it too often, and not drive it too hard, be less likely to see a failure?

Many thanks.

It's not only about use but about design too.
Some amps generate some considerable heat even at idle,these need some quality components near there.
I think some Hypex PSUs are like this.
Mine (Ice Power) is some degrees hotter when in idle than when it is playing is another example (and it's mounted on big heatshinks)

So some overspecification is not the worst idea.

 

[Ze Frog]

Given issues others have had with products by Topping, I would much rather go for the Fosi, even if it is slightly bettered. I have a Fosi BT30D, it's been used extensively for years with no issues at all. Topping in my mind did so well with attaining absolutely impressive measurements etc, but then dropped the ball while at the same time increasing price's. The Topping LA90D for instance isn't exactly cheap, but for all intents and purposes was completely broken on release. Sadly Topping stepped into the standard maximize profit for as little effort as possible just like 90% of manafacturers now.

 

[Kegemusha]

..and the aiyma 07 has sub out

 

[Zek]

..and the aiyma 07 has sub out

No, it doesn't have that, it just has a pass-through signal.

 

[ScofieldKid]

No, it doesn't have that, it just has a pass-through signal.

Uh, we're talking about the A70 in this thread, not the A07...

AIYIMA A70 Stereo Amplifier Review

This is a review and detailed measurements of the AIYIMA A70 stereo class D amplifier. It was sent to me by the company and costs US $190 with 48v @ 5 amp supply. As tested with 48v 10amp GaN supply, it costs US $220. As you see, the A70 comes in vertical desktop configuration. Controls are...

www.audiosciencereview.com

 

[kemmler3D]

For me the real take-away of this thread is I probably never need to spend more than $300 on an amp again, unless I get some very big speakers in a very big room someday.

 

[Anton D]

For me the real take-away of this thread is I probably never need to spend more than $300 on an amp again, unless I get some very big speakers in a very big room someday.

I lean toward your camp.

My only reason for other amps going forward will be as playthings to compare for euphonic purposes.

 

[Talisman]

I will not buy a a Topping amp whatever measurement they have. The company showed behavior that was unacceptable to me considering that they acknowledged they had made a mistake.
In terms of sympathy, I prefer Fosi to Aiyima, it seemed to me that Aiyima followed the path taken by Fosi when he noticed the success of the V3. If this wasn't enough I find the design of the Aiyima to be horrendous to say the least, while the Fosi one is much more elegant and refined, with a certain stylistic imprint of that orange on the knobs.
Now among these four contenders I would simply only buy the Fosi (and I will)