[shenzhenaudio]

TOPPING has released the Pre90 preamplifier & Ext90 input extender today, priced at US$599.99 and US$249.99 separately.
Let's take a first look!

The abundant port interfaces.

TOPPING gives detailed descriptions before purchasing.

Read the parameters here:

If there are no reviews for reference currently, then the following FR is workable:

And, last but not least, the package list:

If there are any questions, comments, or something else are welcomed! SHENZHENAUDIO always here to provide a satisfying service!

 

[pbarach]

Could someone please explain (in English) what these components are supposed to do, and who would need them? (I'm not being sarcastic; I simply don't get what their purposes would be).

 

[tesarpa]

Indispensable for stereo speaker setup. You need volume control, ideally with remote there. For headphones setup, I agree, not much use.

Feature wise, I miss 12V trigger to switch power amplifier on/off.

 

[sajunky]

Dual SMPS with ground loops as an extra feature like in A90?

 

[luckybaer]

Could someone please explain (in English) what these components are supposed to do, and who would need them? (I'm not being sarcastic; I simply don't get what their purposes would be).

It appears to be a pre-amp with a module that allows you to run more components through the pre-amp if you are constrained by the inputs available on the base unit.

At least that’s how I’m interpreting it...
Feel free to set me straight if I missed something.

 

[Fatdoi]

Could someone please explain (in English) what these components are supposed to do, and who would need them? (I'm not being sarcastic; I simply don't get what their purposes would be).

it connects your cd player, dac, pc analog, turntable etc to power amplifier or powered monitor speakers with volume control

 

[royiko]

Interesting. I am more interested in the implementation of single-ended to balanced circuit design? May I know more about that? Currently, experience some clipping sound with RCA-input of A90

 

[sajunky]

Interesting. I am more interested in the implementation of single-ended to balanced circuit design? May I know more about that? Currently, experience some clipping sound with RCA-input of A90

Ground loops destabilising source. It is a biggest problem with A90. Static noise on RCA or just like this...

 

[royiko]

Ground loops destabilising source. It is a biggest problem with A90. Static noise on RCA or just like this...

You mean the problem is from the source? Well, my issue is not static noise on RCA, is like a random sound burst in high frequency. No problem for my XLR source

 

[sajunky]

You mean the problem is from the source? Well, my issue is not static noise on RCA, is like a random sound burst in high frequency. No problem for my XLR source

Then your source is fine. What you hear is just a noise generated by a pair of Meanwell SMPS inside A90. It shouldn't be designed that way, I wrote about it in A90 thread. If you can't find this message refer to this:
https://www.avforums.co.za/index.php/topic,88010.msg1003523.html#msg1003523
and
https://www.avforums.co.za/index.php/topic,88010.msg1003680.html#msg1003680

 

[Voxata]

Then your source is fine. What you hear is just a noise generated by a pair of Meanwell SMPS inside A90. It shouldn't be designed that way, I wrote about it in A90 thread. If you can't find this message refer to this:
https://www.avforums.co.za/index.php/topic,88010.msg1003523.html#msg1003523
and
https://www.avforums.co.za/index.php/topic,88010.msg1003680.html#msg1003680

This is correct, however personally I've never had an issue with loops on my A90. I wish we could see a full PCB shot on the Pre90. Still, I'll be honest the price is WAY up there for Topping.

 

[ivanrocks321]

Might be I a buyer but I have questions.
1. What is the output impedance for the preamp?
2. says it can be a balance or unbalance input converter to either balanced or unbalanced how is this achieved and if it’s a true conversion?

thanks