Topping PA5 II Stereo Amplifier Review

[Bleib]

is possible connect the topping to a dac with balanced out?

Yes

 

[djsolidsnake86]

Yes

but topping doesnt have the classic balanced out

 

[Bleib]

but topping doesnt have the classic balanced out

TRS is balanced. One can connect from XLR to TRS, just buy the right cables
Or TRS to TRS, it's then fully balanced

 

[djsolidsnake86]

TRS is balanced. One can connect from XLR to TRS, just buy the right cables
Or TRS to TRS, it's then fully balanced

so is better connect in balanced?
xlr-trs is not fully balanced?

 

[Bleib]

so is better connect in balanced?
xlr-trs is not fully balanced?

Slightly better, audible...no
It's fully balanced

 

[Seavovk]

is possible connect the topping to a dac with balanced out?

Yes, I connected my SMSL DL300 to Topping PA5 II Black with a Dual TRS 6.35mm to 3 Pin XLR Female Balanced Cable. Fully balanced connection.

 

[djsolidsnake86]

Yes, I connected my SMSL DL300 to Topping PA5 II Black with a Dual TRS 6.35mm to 3 Pin XLR Female Balanced Cable. Fully balanced connection.

View attachment 445268

what is the advantage? i heard that in connections between 2-3 meters the result is the same as rca-rca

 

[Julf]

what is the advantage? i heard that in connections between 2-3 meters the result is the same as rca-rca

Avoidance of ground loops.

 

[Jazigo]

Hi all!

I just wanted to leave a note for those on the fence about this amplifier. I own a set of KEF Q1 Meta (which I super-love) and used them with a amplifier that had a SINAD of about 70-80db (measured it on an oscilloscope without THD+N calculation). I was happy with that setup, but I really wanted to test the speakers on a very good system. So I bought the Topping E50 and PA5 II to test - and oh boy - there was a difference.

I mainly thought that it would be an academical difference, so I was very prepared to just return the topping system after testing it for a day or two. But just after one song, I knew I could not return it.

This will probably not be applicable to all, but if you own a set of KEF Q1 Meta and is running them on ok-ish amplifier (70-80db SINAD), definitely try the PA5 II. I am glad that I did.

 

[Seavovk]

what is the advantage? i heard that in connections between 2-3 meters the result is the same as rca-rca

With a balanced connection, the N5532 input operational amplifier, which is needed to convert the signal from the RCA inputs, is excluded from the audio signal path, since the TPA3251 amplifier chip uses a balanced input according to the datasheet. All parameters of the audio path are better with a balanced connection: THD+N is lower, Dynamic Range is higher, especially noticeable is the greater Сhannels Crosstalk.

 

[DVinylfan]

My Topping PA5 II amplifier is performing perfectly in my Vinyl and CD system, while giving me the convenience of switching on the front panel between the two sources.
Listening to e.g. one of my favourite all analogue vinyl recordings, Fairport Convention's 'What We Did On Our Holidays' (ILPS9092) it sounds better than I have heard it before.
As at my post #1,073, the PA5 II replaced a classic 250 WPC into 8ohms class A/B amplifier that (while 30 plus years old) is still in production and whose current iteration retails around $8K, or 48x the price I paid for the Topping amplifier.
And yet I'm not disappointed, far from it, I'm enjoying the new insights into my music this amp delivers.
Recommended!

 

[john11]

I've blown the 38 volt power supply that comes with the PA5 II.
Over here in UK 38 volt power supplies seem strangely difficult to buy. Could i use a slightly different voltage.
I have three pa5 II in total, could i use one of the 38v power supply to power two amps by soldering an extra cable

Thanks

 

[Roland68]

I've blown the 38 volt power supply that comes with the PA5 II.
Over here in UK 38 volt power supplies seem strangely difficult to buy. Could i use a slightly different voltage.
I have three pa5 II in total, could i use one of the 38v power supply to power two amps by soldering an extra cable

Thanks

If you're good at soldering, you can also use a Mean Well HRP-150/N/N3 with 36 volts, for example. These power supplies allow you to adjust the voltage, and you can set it to 38 volts.
The HRP N3 series is one of the best power supplies for audio amplifiers. It delivers up to 350% power for short periods, with the 150-watt version delivering up to 525 watts for 5 seconds.

You can, of course, also use the cable from your defective power supply and only crimp the connectors for the Mean Well.

 

[stefanovesa]

With a balanced connection, the N5532 input operational amplifier, which is needed to convert the signal from the RCA inputs, is excluded from the audio signal path, since the TPA3251 amplifier chip uses a balanced input according to the datasheet. All parameters of the audio path are better with a balanced connection: THD+N is lower, Dynamic Range is higher, especially noticeable is the greater Сhannels Crosstalk.
View attachment 445514
View attachment 445515

Which is best between simply running a RCA to XLR cable, and having instead RCA plugs at amp side plus a operational amplifier as in this implementation from Topping? Convenience for the user? The previous PA5 in fact had balanced only inputs.

 

[Julf]

With a balanced connection, the N5532 input operational amplifier, which is needed to convert the signal from the RCA inputs, is excluded from the audio signal path, since the TPA3251 amplifier chip uses a balanced input according to the datasheet.

That sounds odd. You can drive a balanced (differential) input from an unbalanced source without any problems, no op-amp needed. Other way around is a different matter.

All parameters of the audio path are better with a balanced connection: THD+N is lower, Dynamic Range is higher, especially noticeable is the greater Сhannels Crosstalk.

Less channel crosstalk is actually better.

 

[john11]

If you're good at soldering, you can also use a Mean Well HRP-150/N/N3 with 36 volts, for example. These power supplies allow you to adjust the voltage, and you can set it to 38 volts.
The HRP N3 series is one of the best power supplies for audio amplifiers. It delivers up to 350% power for short periods, with the 150-watt version delivering up to 525 watts for 5 seconds.

You can, of course, also use the cable from your defective power supply and only crimp the connectors for the Mean Well.

So i couldn't run two amps off the one power supply

 

[Seavovk]

Less channel crosstalk is actually better.

-106 dB on Balance input less than -90 bB on RCA input (above meant a larger negative value in dB)

That sounds odd. You can drive a balanced (differential) input from an unbalanced source without any problems, no op-amp needed. Other way around is a different matter.

This is in theory, but in fact wiith a balanced connection, the N5532 input operational amplifier excluded from the audio signal path, since the TPA3251 amplifier chip uses a balanced input according to the datasheet by default.

Which is best between simply running a RCA to XLR cable, and having instead RCA plugs

Dual TRS 6.35mm to 3 Pin XLR Female Balanced Cable is better

 

[Julf]

-106 dB on Balance input less than -90 bB on RCA input (above meant a larger negative value in dB)

OK, a larger negative value means less crosstalk.

This is in theory, but in fact wiith a balanced connection, the N5532 input operational amplifier excluded from the audio signal path, since the TPA3251 amplifier chip uses a balanced input according to the datasheet by default.

Just wondering why they did that, as that opamp isn't needed. As I wrote, there is no problem (in theory or practice) with driving a differential, balanced input from an unbalanced output.

 

[Seavovk]

Just wondering why they did that, as that opamp isn't needed. As I wrote, there is no problem (in theory or practice) with driving a differential, balanced input from an unbalanced output.

As far as I understand this circuit is implemented in all amplifiers based on TPA3251 and TPA3255.

 

[Julf]

This circuit is implemented in all amplifiers based on TPA3251 and TPA3255.

Why? Maybe to provide additional gain? Higher input impedance?