Topping LA90 Discrete Amplifier Review

[babadono]

Does this amplifier have any operational amplifier in the signal path, or maybe it is a 100% discrete circuit from input to output?

I would assume yes...but I sure want to take one apart. Don't think we will ever know what is in the black encased modules. Just received a 9" 2mm T handle hex key for this very purpose.

 

[babadono]

what the? replied twice from my phone and it ain't here? sometimes this stuff baffles me...anyway no I have not taken either of my amps apart. Too busy enjoying listening to them.

 

[LucreciaBorgia]

Yes.

LA90 Discrete Power Amplifier-TOPPING

View attachment 358576

Does somebody knows the Imput impedance of the LA90D ? Strange that is nowhere to be found, it is an important criteria....

 

[staticV3]

Does somebody knows the Imput impedance of the LA90D ? Strange that is nowhere to be found, it is an important criteria....

The LA90 had 20kΩ Zi, the LA90D is probably similar.

 

[LucreciaBorgia]

Not so good...I was expecting at least 40/50 KOhms....

 

[LucreciaBorgia]

Is there a fuse in the device (or in the power supply) ? I can't see any ...

 

[babadono]

The LA90 had 20kΩ Zi, the LA90D is probably similar.

That would be balanced I think. I believe I saw John chime in somewhere that that is what he recalled but he was not 100% sure. If putting some kind of adapter or unbalanced cable it would probably be half that so 10K?

 

[babadono]

Can I bother you to tell me where is the sale? Tank you very much in advance

Sale ongoing again...12% off list. At least at ShenzhenAudio for a few more days

 

[babadono]

Perhaps if/when they go on sale again I may purchase another pair to run the mids as well.

Done. Two more on their way.

 

[LucreciaBorgia]

Do you need a special preamplifier to run 4 blocs, or ?
Is something like the SPL 2control up to the task ?
I would be also interested to run 4 blocs as my LS have bi-wiring = 1 bloc for each voice of each LS

 

[babadono]

I have a pretty elaborate set up and run each one off a dedicated output. But the input impedance as far as we know is 20k ohms so 2 in parallel should be 10k. Any decent output should be able to drive 10k.
SPL 2control output impedance spec'd at 75 ohm. 21.3dBu Max out level. Should easily drive 2 LA90s in parallel.

 

[babadono]

Dang, got two pairs now. All 4 in bridge mode. 2 running the mids, 2 the tweeters in a 3 way active (4 way if counting subs). Dang, just dang.

 

[Ismapics]

Friends: I can't find this amp in the Electronics Review Index. It does not appear that I can see under Topping. Please let me know if you can see it there

Audio Electronics Review and Measurements Index

Master table and index of all audio equipment reviews and measurements.

www.audiosciencereview.com

Chees, IM

 

[Grael]

Friends: I can't find this amp in the Electronics Review Index. It does not appear that I can see under Topping. Please let me know if you can see it there

Audio Electronics Review and Measurements Index

Master table and index of all audio equipment reviews and measurements.

www.audiosciencereview.com

View attachment 380074


Chees, IM

This index seems to be frozen in time, "Last review date : 2021-10-20"

You will find the amp in this other index

Master Audio Review Index

www.audiosciencereview.com

 

[Ismapics]

This index seems to be frozen in time, "Last review date : 2021-10-20"

You will find the amp in this other index

Master Audio Review Index

www.audiosciencereview.com

Sorry about being a neophyte but I can't find it, not sure where to click

 

[Grael]

Sorry about being a neophyte but I can't find it, not sure where to click

Go to the "Audio Electronics" section, then "topping amp", "all keywords" in the search box (or use the advanced search)

Master Audio Review Index

www.audiosciencereview.com

 

[babadono]

isn't this the review?

 

[Ismapics]

isn't this the review?

Yes, I am just pointing out that the review is not present in the Review Index.

 

[staticV3]

Yes, I am just pointing out that the review is not present in the Review Index.

It is in this one:

 

[Ismapics]

It is in this one:
View attachment 380170 View attachment 380171

It is in this one:
View attachment 380170 View attachment 380171

Here is not present in de D-Base. https://www.audiosciencereview.com/forum/index.php?pages/Audio_Equipment_Reviews/