Topping Pre90 Review (preamplifier)

[maruko]

Nothing, only the D90

 

[misterdog]

You're making it way too complicated.

It's an analog preamp. It selects analog sources and applies attenuation, and can be controlled through a remote.

If you only have one source that has its own volume control, there is literally no point in using this.

I'd say that if you need this, you would simply know that already based on your system. This isn't something you cram into your system for better numbers.

The only proviso being that if you have to attenuate your DAC's output by a reasonable amount then you might benefit from a preamp.

 

[Geared4me]

I received the pre90 tonight from Apos Audio. I am going to let it warm up to room temperature and then I will be comparing it to my Marantz SC-7S2 preamp. I put the pre90 on top of the 7s2 and the pre90 is comically small in comparison, or the Marantz is comically large in comparison depending on your perspective. The pre90 weighs about 2lbs and the Marantz weighs about 48lbs, too funny. Can a newfangled 600 usd preamp take on an older 8k usd preamp? Based on the measurements I am guessing yes and maybe even let more of the sound through. To be continued

 

[misterdog]

Received mine on Thursday, took a day to come on song (though burning in of hi-fi is nonsense obviously )
Be interesting to know if the review sample had been bench run before testing or was factory fresh ?

Feeding with SMSL M400 (now in fixed output mode, 5.3V ).
Though my Thesycon ASIO driver seems to have disappeared after a Win 10 update which is a pain.

There is more bass, a lower noise floor and more micro detail, so I'm happy.

My previous pre was a DIY Bruno Putzeys design so was no slouch.

( I think that should read - 18dBu)

Feeding Neurochrome monoblock amplifiers into Quad 989 ESL's.

It arrived in a nice box (black ) has a nice knob feel and the relays are quiet in operation.
My only small criticism is that the remote is a little omnidirectional.

 

[Geared4me]

The answer to my previous post is an emphatic YES! The pre90 is a fantastic preamp. The channel balance is perfect and the pre90 lets every little detail through allowing the soundstage to portray its natural width, height, and depth. It is neutral in the best sense of the word and sounds fantastic. Compared to the Marantz SC-7S2 the Marantz has a slight boost in the upper bass and midrange that makes it sound a little warmer and fuller, the difference is small but definitely there. I can easily see someone preferring the Marantz for its transparency with warmth approach over the pre90s more flat balance. The pre90 counters with an expanded soundstage by letting every little detail through while NOT sounding sterile or clinical in any way, just honest to the source. I am astounded by how well the pre90 performs in my system. The pre90 has a few things that are minor annoyances, the remote sensor is picky about aiming, the volume makes a clicking noise every time it is adjusted, and when the display is off you have to press a button to wake it up before making an adjustment. Other than those three minor annoyances I think the pre90 is a perfect preamp. My system, for reference, is an nvidia shield and oppo bdp-105d as sources to the pre to a Starke Sound ad4.320 amplifier to PSB Imagine T3 speakers. I will be adding a Gustard X16 dac to the mix in a few days and I fully expect that the pre90 will show its abilities to the fullest. If you are in the market for a preamp the Topping pre90 is a no brainer. I am in no way affiliated with Topping and I have not been compensated in any way for my opinion. I bought the Topping pre90 with my own money out of curiosity and I am so glad that I did.

 

[Geared4me]

As far as the remote sensor being picky goes, it is quite omni-directional with the supplied remote. I used the learning feature on my universal remote to capture the pre90s remote signals and the pre90 receives the signal better from the universal remote. It is not perfect but it is better with the universal remote so it seems that the remote and the pre90s sensor are both at fault here.

 

[Dichotome]

It does.

@JohnYang: You said it does SE to balanced conversion. Can I just clarify, is it simply outputting a SE signal via the XLR output, or is it truly converting a SE input to a fully balanced output ?

 

[Geared4me]

I haven't opened it up to look for myself but I have no reason to doubt it when they say "conversion".
https://shenzhenaudio.com/products/...es-audio-nfca-modules-2-rca-4-xlr-combination

 

[Veri]

@JohnYang: You said it does SE to balanced conversion. Can I just clarify, is it simply outputting a SE signal via the XLR output, or is it truly converting a SE input to a fully balanced output ?

The balanced output is always true balanced, regardless of input. You can be sure of that.

 

[misterdog]

Using the RCA input from my phono stage >XLR out, I have to increase the volume from -20dB from my M400 DAC to around -08dB for my phono stage.
So I suspect the output is just pseudo balanced.
Regarding the relay clicks, you cannot avoid them, they are not that intrusive and how often are you changing volume, once set just enjoy the 'extra' music.
Bought mine from HiFiGo £453 to the UK inclusive.

 

[Veri]

Using the RCA input from my phono stage >XLR out, I have to increase the volume from -20dB from my M400 DAC to around -08dB for my phono stage.

It is true balanced. This is simply due to the wild variation between your phono stage and the M400 which has a hotter than standard output voltage (>5V rather than nominal 4.0V).

 

[misterdog]

Maybe @JohnYang1997 could clarify.

 

[JohnYang1997]

Of course it's true balanced...

 

[Mareli63]

Of course it's true balanced...

Looking at the picture from inside it looks like there are 2 muses 100uf bipolar coupling capacitors and only 8 or 9 relays for volume control.
My guess is the balanced signal is converted to single ended then volume is applied then signal is converted back to differential.
For 128 steps balanced volume control you need double the numbers of relays, and also 4 coupling capacitors.
Correct me if I am wrong.

 

[JohnYang1997]

Looking at the picture from inside it looks like there are 2 muses 100uf bipolar coupling capacitors and only 8 or 9 relays for volume control.
My guess is the balanced signal is converted to single ended then volume is applied then signal is converted back to differential.
For 128 steps balanced volume control you need double the numbers of relays, and also 4 coupling capacitors.
Correct me if I am wrong.

Yes. That's correct. There is single ended to balanced conversion. So it's true balanced output. You do still get basically all the benefits of balanced input and balanced output. Minus some noise performance but this is almost inevitable.

 

[Mareli63]

Yes. That's correct. There is single ended to balanced conversion. So it's true balanced output. You do still get basically all the benefits of balanced input and balanced output. Minus some noise performance but this is almost inevitable.

Are those coupling capacitors necessary? Can they be bypassed?

 

[VeerK]

@JohnYang1997 how’s the progress with the power amplifiers?

 

[jruser]

Does a dac (gustard x16) with a 357ohm XLR output impedance work well with this? Any effects on frequency response? I realize it isn't quite the 15:1 impedance ratio people look for.

 

[auronthas]

Want to know how PRE90 integrate into my system (D90/A90)

Digital Source : 1) Network Media Player via USB
Digital Source : 2) Network TV/PS4 via Toslink

Digital source <USB/Toslink> D90 <balanced XLR> A90 <balanced XLR> Integrated Amplifier <speaker cable> speaker

Currently A90 is served as analogue pre-amplifier (speaker system) bypassing in-built pre-amp of integrated amplifier.

I can choose digital source from D90 remote control either USB or optical or even bluetooth or coaxial.

Downside is I need to adjust A90 pre-amp volume knob , gain switch manually.

Is Pre90 redundant for my setup? Only differences/advantages is analogue volume control and remote control but less headphone amplifier ?

 

[auronthas]

Would there be EXT2 with multiple RCA single ended input/output soon?