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WolfX700 Measurements of Topping Pre90/Ext90 Preamplifier/ Extender

mocenigo

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On pre90 you can select rca output, xlr output, or both at the same time.

Thank you very much. This is in my opinion a very important feature and I appreciate it being there, even though I personally do not need a pre at the moment. On the basis of how your NCFA circuit works, I now know I can recommend it to anyone that is shopping for a preamp.

The 768khz issue seems not fixable. D90 can play 768khz without issue here. But some users have the issue. And frankly who really needs 768khz...

I know, it is just because I am a bit OCD and I do not like that there are bugs, but of course this is not an important one. 768khz is in my opinion useless. Pass this on to the team that developed the D90 (not sure if you were involved or not): that little thing sounds just great. And the combo D90+L30 (I know you are the mastermind of the latter) is simply lovely with my AKG K812. Congratulations.
 

Dave O.

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Thanks for the information. Would have been nice to keep them half width and same depth as pre90 - could have made a really nice stack.

Any chance that Topping will design and develop a pure streamer (no dac, no hp amp) to match Pre90 or Ď30Pro... I'm quite sure there are many others like me who want to stream from Tidal and / or Quboz without having to deal with a computer and without compromising sound quality.
 

Atanasi

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The 768khz issue seems not fixable. D90 can play 768khz without issue here. But some users have the issue. And frankly who really needs 768khz...
As for firmware bugs, is it possible to fix initialization issues when connecting a DAC through an isolator like Intona? I have E30, and it often fails to initialize without adding a hub in between. This is common with XMOS chips, but I heard it can be fixed through firmware.

https://intona.eu/en/support/answer/1235
 
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Harmonie

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Pre90 is not designed to be used with A90. A90 is the center of the desktop system. Pre90 is to design to pair with dedicated power amp in a HIFI system where the speakers are the only needed outputs.

Is there any advantage to put the Pre90 between a D90 and speakers.
Putting it differently, will there be any sonic advantage running the D90 in pure DAC mode and avoid it's volume control in favor of Pre90's one ?
 

JohnYang1997

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Is there any advantage to put the Pre90 between a D90 and speakers.
Putting it differently, will there be any sonic advantage running the D90 in pure DAC mode and avoid it's volume control in favor of Pre90's one ?
I won't speak about sonic. Technically, you get better SNR this way.
 

typericey

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Our first up coming power amp is a integrated amp.

Can you give us a teaser to the form factor? i.e. similar dimensions to the 90-series? If you are feeling generous, you are free to share other specs too. :p

(Sorry, off topic)
 

VeerK

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I won't speak about sonic. Technically, you get better SNR this way.
Is the integrated power amp the “level 1”? Did you finally decide on how to handle chassis size and the ears? Wolf mentioned you had made progress, interested to see some hints :)
 

elevensheep

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I won't speak about sonic. Technically, you get better SNR this way.

hi John

I intend to buy the Pre90 to use in my living room hifi system.

Streamer will be a Lumin u1 mini - is that output impedance okay?

secondly, is there a particular type of power amp that would work the best with Pre90? I intend to pair it with a Naim 250DR power amp.

Thanks
 

Angsty

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Maybe it's the opposite? I didn't want to reply to this thread but as you are actually giving some valuable points. Here's the deal.
599 now only worth 549 in June. That's half of the price difference.
The amplification is reduced in half but the same same time same structure this doesn't reduce much money only the board occupation. 2 relays are basically evening out the difference of the different amplification circuit. Then you add even more relays not only for the volume control but for switching and screen etc. Also would any one think a 300 dollar extender unit sane? Even 249 is a bit high for many. But the extender itself cost quite a lot to make so we eased a bit to the main unit. Hence 599+249. Reducing another 50 bucks won't make a meaningful difference for people commented above as you see. So that's it.
Also from a different perspective pre90 is not to compete with A90. It's a dedicated preamp. Think about it.
Our first up coming power amp is a integrated amp. So that shouldn't need this either. So we don't at first expect this to sell like other products. This is targeted to specific people. It's also a preparation for the higher end monoblock poweramp. 599 is really not that much. 849 for multiple inputs and all the features built into it is not unfair also. If you look around the competition. There's simply no competition. H16 from gustard is cheaper yes but with much worse performance especially when reduced volume. If one doesn't care about the performance, safe volume, saved volume features on pre90, H16 is the way to go. Go get it. If remote is not essential, A90 is there for you. And go go get it.
Pre90 doesn't make much sense because it doesn't mean to.
The new A30pro and D30pro will be a very good deal for most people here. :)

Every product cannot cater to every price segment. Topping units are a good deal less expensive than the comparative Bryston units I use daily, even when purchased used.
 

didi

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In absolute sonic terms, which preamplifier matches Benchmark AHB2 best - Topping Pre90 or Benchmark LA4?
 

righthookmike

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so what's the consensus?Is it good? I won't be using any legacy gear. My amp right now is a jungson 88d deluxe model but may change to another class a at some point. I only stream music and I don't believe that will change. I can't afford a benchmark pre. the feature set of this preamp is exactly what I need.
 

Flo

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Pre90 is not designed to be used with A90. A90 is the center of the desktop system. Pre90 is to design to pair with dedicated power amp in a HIFI system where the speakers are the only needed outputs.

@ John Yang nihao!
But can't you just put the A90 between the Pre90 and the amplifier, so you select HPA when using headphone and switch to PRE when listening on speakers?
 

ARAJO

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If you don’t need XLR and you don’t need remote is there any advantages of the Pre90 over L30 for pure HIFI I.e direct to power amp.
 

Peternz

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I asked this in the pre90 review thread, please excuse me for asking this here too, but is there anything to be gained by putting the pre90 between a Oppo UDP-205 and a power amp vs just running the Oppo directly into power amp and using it's digital volume control? Many thanks...
 

MRC01

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Theoretically, there could be a difference. With digital volume controls, as you turn down the volume SNR typically drops 1:1 with it. Turn it down 30 dB and you also get 30 dB lower SNR. Analog volume controls can be worse than this, or better.

For example, if I read Amir's Pre90 measurements correctly, it has an excellent SNR of 126 dB at 4 V output. But when you turn its volume down to 50 mV output, its SNR is 85 dB. In other words, reduce volume by 38 dB (4 V to 50 mV) and SNR drops 41 dB. Compared to other headphone amps and DACs, 85 dB at 50 mV is good but not great. The UDP-205 may be better or worse, which is to say, putting the Pre90 in between might make a difference, for better or for worse. However, in this case I doubt it would make a difference since the Pre90 happens to be close to 1:1 as you lower the volume.
 

tmtomh

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I believe the Oppo's volume control operates inside the DAC at 64-bit float. I am so not a technical expert on this, but my impression was that this implementation reduces the SNR loss from reducing the volume. I could be wrong, though.

My own experience, and my opinion from what I've read, is that if your Oppo-->power amp chain is giving you sufficient gain as-is, there's no benefit to putting a preamp in between them.

If gain is not an issue (and you don't need additional source inputs beyond what the Oppo offers), then adding a preamp becomes basically just substituting the preamp's volume control for the Oppo's. Even if the premp's volume control performs better (which is questionable), you only get those gains if you are able to run the Oppo at 100% volume and use the preamp to control gain. Even if the preamp's volume control is better, you also have to consider how much you have to turn down the Oppo's volume vs how much you'd have to turn down the preamp's volume. Because a preamp adds gain, you might have to run the preamp's volume control at, say, 30 or 40% to play at the same volume as the Oppo's volume control at, say 80 or 90%. Whether you get better performance by running a slightly better volume control at 30% versus a slightly less-good volume control at 80% is anyone's guess.
 
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