Topping PA5 (TPA325X) : Is a modification worth it? ?

[vankovich]

Sorry, the pics are somewhat out of order as I attempted to delete a duplicate image.
Vanko

 

[TNT]

Nicely done. A mod I could have liked to do myself if I owned the amp. Maybe also XLR connectors?

They should do a version with Speakon, single input only with XLR and no pot/fixed, standard (~27dB?) gain.

//

 

[U101222]

I find the PA5 to be a bit of an odd duck with pro audio balance inputs and consumer level small 5 way binding post outputs. Upon receiving mine I found foremost reaction was the replacing the later with Speakons as the amp was to be used whenever, wherever and my history with binding posts have relegated them to the ash heap upon discovering Speakons. The following are my experience replacing the binding posts.
Cheers,
Vanko
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very nice work but the slits in the back plate aid ventilation. Removing them can be dangerous. Of course there is no more room for them now….

 

[daniboun]

Well done, interesting mod )

 

[U101222]

Meant AO200 or also DA9. Curious if PA5 has much better soundstage as Class D is known to have much smaller soundstage.

In general, no. The claim is too broad to have any meaning. With respect to amplifiers with a small amount of negative second order distortion, it is knows. As PDQ Bach said, A Chaconne a son gôut.

 

[vankovich]

very nice work but the slits in the back plate aid ventilation. Removing them can be dangerous. Of course there is no more room for them now….

Oh I think there is more that enough ventilation,
VANKO

 

[BPT]

Anymore mods being done on the PA5: lower noise 38V DC supply, lower impedance DC power connection? I replaced the AC cord with a heavier gauge using a C14 to C7 adapter and reduced the length of the power umbilical cord in half with some minor subjective sonic improvements. If I can find a used B & K precision power supply cheap--might give it a go.
BPT

 

[daniboun]

Anymore mods being done on the PA5: lower noise 38V DC supply, lower impedance DC power connection? I replaced the AC cord with a heavier gauge using a C14 to C7 adapter and reduced the length of the power umbilical cord in half with some minor subjective sonic improvements. If I can find a used B & K precision power supply cheap--might give it a go.
BPT

I made my own LLC PSU for the PA5, The Connex SMPS300R (single rail) has an excellent ripple (JLESTER measured it VS a Meanwell, and it performs even better). I am also using a special Audio Filter for the AC inputs and good quality cooper cables.

This is a 36V / 8.3A (stock, can be ajusted @ +-5%) 300W LLC SMPS PSU.


Some pictures :

 

[BPT]

very nice work but the slits in the back plate aid ventilation. Removing them can be dangerous. Of course there is no more room for them now….

Just flip it over so bottom vents face upwards.
BPT

 

[daniboun]

Just flip it over so bottom vents face upwards.
BPT

Both bottom and top cover have ventilation holes )

 

[daniboun]

Here is a little table that might be useful)




Meanwell LRS-350-36 vs SMPS300RS

the Meanwell has a higher switching noise (65kHz) (192mV-pp).

Connex :



Meanwell :

 

[BPT]

Both bottom and top cover have ventilation holes )

Mine doesn't. It has bottom and both sides.
BPT

 

[audioarchitech]

I'm going to upgrade the binding posts using GR-Research's Electra Tube Connectors.

 

[audioarchitech]

@vankovich

Did you check the quality of the binding posts, take a magnet to all the parts? Ferromagnetic? Do you think you noticed any improvement after installing Speakon connectors?

 

[vitopro]

Anyone has discovered what opamp are used in this amp?

 

[daniboun]

Anyone has discovered what opamp are used in this amp?

Not yet... you would have to unsolder the black box to find out more...

 

[usa_satriani]

Hello,

Do you think these amps are good for compression drivers and tweeters in a multi way active speaker?

 

[BPT]

Yes. Should be XLR balanced connection.
BPT

 

[usa_satriani]

Yes looking for balanced amp to pair with RME soundcard.
Quite difficult to find class ab balanced amp these days event from traditional PA manufacturers...

Topping la90 looks good at 3* price

 

[esl 63]

Probably... it is dead quiet. Otherwise put a 10 ohm resistor in series. Damping factor is not important above resonant frequency.
Actually it will lower the distortion.