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Topping D90 suitability for use as a Pre Amp

AMCQB

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Hi - there isn't enough information that i can find on how to determine suitability of DACs and utilising their Pre out (digital vol) direct into power amps. I'm hoping someone can help.

I have an old 90s high end system, Linn Kaber speakers (no crossovers), 3x Linn LK100 power amps running active crossovers. I had this connected to a Linn Kairn and then fed by a Chord 2Qute. For a bit of fun as i also has a Chord Mojo i dropped this in. Chord Mojo in place of 2Qute was so similar i was minded to sell it (2QUTE cost £1000 and was model b4 QUTEST). I was then intrigued what it would be like to use mojo as a pre. Now this surprised me, in this system mojo direct was so much more transparent and the bass more tight. I promptly sold the 2QUTE and the Kairn and used the mojo in the main system. Of course a short while later the battery gave up and its no solely the DAC and Pre now.

Topping D90 has pigued my interest. My view is with diminishing returns (and experience with Chord 2Qute) is the jump to Hugo 2 will not be worth the vast money (for me anyway). D90 has a bit of mixed view out there, some clouded by preference to delta sigma vs R2R vs hybrid. Some also most likely to 'hype' which you guys have less time for.

My question is based on the specs of the D90 vs Mojo and then the amps will the D90 work well and exceed the mojo ?

Amps are run in series, Mojo is connected via 3.5mm to RCA to 1st amp, does treble and is linked via RCA to the 2nd on mids and then the 3rd on bass. Amps are 50watts/8 ohms and 90 watt/4 ohms, voltage gain is 28.7db and input impedance is 10kilohms (which i gather is low and not ideal)

look forward to views, especially from Topping
 

trl

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As long as you're OK with selecting the desired level via the two UP/DOWN switches (no rotary knob here) or from the Vol+/- from the remote control, I don't see any issues. Just double check the volume level on the front screen before powering ON your speaker amps.

Also, do check
too.
 
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A

AMCQB

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I had hoped for more feedback, without it i took a risk and purchased the D90 from Amazon.com.au, delivery the usual awesomeness of next day :) I was initially struck by how clean and open the sound was, this was the initial 15mins or so. It was quite soon after this i noticed things were really not right. The presentation lacked depth and dynamics. Functionally i also encountered an issue early on with the remote, if you accidentally hold the button it shoots up in volume. This was a deal breaker, DACs duties include tv/movie etc and includes operation by wife n kids. I just knew at some stage someone would sit on the remote and then blow up three amps and speakers. Going down the addition of adding Topping A90 was a no go due to the lack of sofa seated remote control. I started to come to terms with spending more $$$. D90 was returned to Amazon and an RME ADI2 DAC FS was ordered from another retailer. I think crucially what the RME has that the D90 and most other DACs seem to lack is a relay that can adjust the gain to better match different configs of power amp. Usually the role of a dedicated pre amp. At almost double the price i think its well worth it for my use case. I have been back and forth with it vs the old Mojo and its night and day in a number of ways. At lower volumes the loudness function works a treat as it engages and disengages automatically with level and is fully adjustable. I played around with using the phones output vs the mojo and this is more similar in presentation. I wonder is that because a power amp is expecting 'line level' which although the volts can be the same as 'phones' the current or something is quite different. Only way i can explain it is Mojo gives a bit of a "thick" presentation and the RME phones output is very similar (bit less thick though). RME with line out and everything opens filling the room, its a grander scale and i can raise the volume much more and the bass is more dynamic. Mojo vs RME IEMs output into Sennheiser ie800s is quite similar although i notice the RME is more linear, slightly clearer, Mojo bit warmer. RME has cross-feed options to explore.....
 

trl

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Functionally i also encountered an issue early on with the remote, if you accidentally hold the button it shoots up in volume. This was a deal breaker, DACs duties include tv/movie etc and includes operation by wife n kids. I just knew at some stage someone would sit on the remote and then blow up three amps and speakers.
Isn't this a normal behaviour on any remote? Is it the volume-up speed too high and you think it should be lowered? If so, then maybe it can be adjusted by a firmware upgrade, @JohnYang1997 might know.
 

JohnYang1997

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Isn't this a normal behaviour on any remote? Is it the volume-up speed too high and you think it should be lowered? If so, then maybe it can be adjusted by a firmware upgrade, @JohnYang1997 might know.
The behavior was mentioned before. Sadly it's not upgradable as it's in the microcontroller. At the time we didn't develope the way to upgrade microcontroller firmware via xmos. D70s and newer do.
 
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trl

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All amplifiers should have an input low-pass filter to protect it's inside electronics.

However, I'm not aware of any high frequencies delivered by D90.

You may purchase a preamp with a normal volume knob if you're worried about increasing the volume very fast or you can set the D90's volume to a comfortable-high level (e.g.: 50%) and setup the intermediate levels from the operating system (or from the software player).
 

Willem

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I also use my ADI-2 as a preamp and I am more than happy.
 
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