Topping Pre90 Review (preamplifier)

[gvl]

Cleaner sound and convenience of a physical knob? I currently use an in-line attenuator (Pearston IMA-1030) between the D70 and the monoblocks to keep the D70 at optimum level at normal listening levels with room to spare (between -6 and 0 dB) and adjust the D70 output level via remote. The NC500MP does not have adjustable gain unlike my class AB amps so front-end pairing is a little tricky.

I get the knob, but cleaner sound? Maybe, maybe not. What dB volume do you need to run the D70 for your normal listening levels w/out the attenuator?

 

[Gyroscopics]

Gustard said best to not use it's volume control as it would degrade the sound.......Thus I guess I need a preamp....

That's exactly the reason why I currently use in-line attenuators to keep my DAC at optimum level (see above post). But there is no doubt, in-line attenuators affect the signal given all the impedance matching complexity. A stepped attenuator (like the Pre90 or Freya-S) is the best but more expensive solution. At that time the Pre90 was not yet available, and Freya-S was discontinued. Hence I went with the in-line attenuator solution for the time being. I tried the Nobosound NS-05P (or Little Bear equivalent) but the "Pearston in-line attenuator + D70 digital volume" solution sounded cleaner at various volume levels.

 

[Gyroscopics]

I get the knob, but cleaner sound? Maybe, maybe not. What dB volume do you need to run the D70 for your normal listening levels w/out the attenuator?

-35 to -25 dB without the attenuator. With the attenuator set to -20db, l could set the D70 digital output level between -10 to 0 dB for my needs. -6 dB at normal listening level, 0 dB when I want to crank it up. The headroom is also necessary to play DSD (due to inherent lower signal level).

My attenuator has 3 settings: -30, -20 and -10dB of attenuation. It was a pretty neat solution at that time and I'm still happy with it. I may not need the Pre90 afterall. Just toying with the idea. What do you think?

 

[gvl]

-35 to -25 dB without the attenuator. With the attenuator set to -20db, l could set the D70 digital output level between -10 to 0 dB for my needs. -6 dB at normal listening level, 0 dB when I want to crank it up. The headroom is also necessary to play DSD (due to inherent lower signal level).

My attenuator has 3 settings: -30, -20 and -10dB of attenuation. It was a pretty neat solution at that time and I'm still happy with it. I may not need the Pre90 afterall. Just toying with the idea. What do you think?

I think that D70 is very quiet, and you can safely go to -35dB digital attenuation without any perceived effects and ditch the passive attenuator, this will also help to avoid the somewhat increased distortion that starts to creep in at -12dB. If you must have the knob and more inputs then the Pre90 may be a solution, or perhaps just get another top-performing quiet DAC that has a physical knob and sell the D70. If you are listening to DSD a lot it maybe another reason for the Pre90 to avoid internal conversion to PCM on the DAC for volume control there.

 

[Pdxwayne]

That's exactly the reason why I currently use in-line attenuators to keep my DAC at optimum level (see above post). But there is no doubt, in-line attenuators affect the signal given all the impedance matching complexity. A stepped attenuator (like the Pre90 or Freya-S) is the best but more expensive solution. At that time the Pre90 was not yet available, and Freya-S was discontinued. Hence I went with the in-line attenuator solution for the time being. I tried the Nobosound NS-05P (or Little Bear equivalent) but the "Pearston in-line attenuator + D70 digital volume" solution sounded cleaner at various volume levels.

Good to know. I want both xlr and rca outputs for amp and sub....I guess Pre90 would work the best. Thx!

 

[Gyroscopics]

Or perhaps just get another top-performing quiet DAC that has a physical knob and sell the D70.

Any suggestions? I like the warmer sound and wider & deeper soundstage of the D70. I have the SMSL SU-8 and I find it clinical.

 

[gvl]

Any suggestions? I like the warmer sound and wider & deeper soundstage of the D70. I have the SMSL SU-8 and I find it clinical.

The warmness and the depth are most likely imaginary, can't help with that. Topping D30 Pro is super quiet with 128dB of DR, so it is a good candidate to be used for volume control on a DAC. Check the discussions about it here for any known issues.

 

[Gyroscopics]

Good to know. I want both xlr and rca outputs for amp and sub....I guess Pre90 would work the best. Thx!

Yes I use my D70's RCA output for subwoofer (Rhythmik L12) and the XLR output for my amp.

Just a side note for anyone looking for single-ended low-cost pre-amp solution between their single-ended DAC and AMP, the JDS Labs Atom is a very good pre-amp for that purpose. Yes, it is the cheap headphone amp, but also an excellent pre-amp on its own. I use it on my other system (home gym): Topping E30 --> JDS Labs Atom --> Parasound A23 --> 705s2

 

[Pdxwayne]

Yes I use my D70's RCA output for subwoofer (Rhythmik L12) and the XLR output for my amp.

Just a side note for anyone looking for single-ended low-cost pre-amp solution between their single-ended DAC and AMP, the JDS Labs Atom is a very good pre-amp for that purpose. Yes, it is the cheap headphone amp, but also an excellent pre-amp on its own. I use it on my other system (home gym): Topping L30 --> JDS Labs Atom --> Parasound A23 --> 705s2

My x16 has the DC issue with RCA when power off, thus another reason to have a preamp in between.

Regarding your single ended solution, you meant Topping E30 to JDS Labs, correct? L30 is not a dac.

 

[Gyroscopics]

The warmness and the depth are most likely imaginary, can't help with that. Topping D30 Pro is super quiet with 128dB of DR, so it is a good candidate to be used for volume control on a DAC. Check the discussions about it here for any known issues.

Thanks, I see the issues discussed in the ASR D30 Pro thread, typical for new product. I don't want to be one of the early-adopters facing these issues. I would rather wait till a new firmware is released or hardware is fixed (worst case). Thanks for the suggestion.

 

[Gyroscopics]

My x16 has the DC issue with RCA when power off, thus another reason to have a preamp in between.

Regarding your single ended solution, you meant Topping E30 to JDS Labs, correct? L30 is not a dac.

Correct, my mistake, it's the E30. I'll edit my post.

 

[hmscott]

I am thinking, again, to get the pre90. Main reason is I just went back to doing gustard x16 dac direct to amp. To get mqa to work, my node2i need to be in fixed (max) volume mode. It means I need to use x16 to control volume. Gustard said best to not use it's volume control as it would degrade the sound.......Thus I guess I need a preamp....Any cons in doing that other than I may hear no improvements? Pros?

If you only have 1 device source, and volume reduction is the only function - no active gain needed, the Pre90 would be overkill for the application.

Besides the additional cost, there are the aspects of having another active signal amplifying device, you should be able to get by with a less expensive passive volume control device instead, and with good build components, there shouldn't be any effect on the audio quality.

Sorry, I don't currently use a passive volume control so I cannot give a personal use recommendation, perhaps someone else can give a recommendation for one they use?

I did a quick search on Amazon for "passive volume control", these are names I know and they look good enough to check out. And, there are more to look at one Amazon too.

Amazon.com: Schiit SYS Volume Control and 2-Input Switch: Home Audio & Theater

Amazon.com: Nobsound Mini Fully-Balanced/Single-Ended Passive Preamp; Hi-Fi Pre-Amplifier; XLR/RCA Volume Controller for Active Monitor Speakers (Black): Home Audio & Theater

Spoiler: Photo of Back Panel with XLR inputs and outputs

Photo of back panel with XLR inputs and outputs, Douk Designed - I'm looking at getting a tube amp from Douk Audio Designs too.

And, here is the front panel, nicely sized for stable volume control use than their smaller RCA/RCA only models.

Amazon.com: Nobsound High Precision Passive Preamp Volume Controller VOL Control HiFi Preamplifier ALPS (RCA&HiFi Version, Black): Home Audio & Theater

A little more searching, I remembered this gem from a review I'd read (and seen on Youtube), perhaps overkill too - it switches 4 devices, but it got good reviews:

Amazon.com: Bellari PP532 Passive Preamplifier: Electronics

Then I searched on Youtube and was reminded of the Schitt Loki Equalizer that can also be switched to a passive bypass mode, and you might enjoy the equalizer functions, hopefully, these active devices do not degrade the audio signal audibly:

Schiit Audio: LOKI MINI+ HIGH-QUALITY 4-BAND TONE CONTROL $149 ROLLING BACKORDER. SHIPS 4-6 WEEKS.
"The Silent and Transparent Companion
Loki Mini+ transforms your system without getting in the way, or making itself known. Forget noisy, bad-sounding equalizers you may have used in the past. Loki Mini+ uses a single, discrete, current-feedback gain stage, coupled to passive LC filters for 3 bands, plus a gyrator for the bass. It also uses sealed Alps potentiometers with rational adjustment ranges to allow for fine control. Coupled with a 100% passive bypass setting, Loki Mini+ offers the transparency and flexibility you need." - Not sure if the Passive Bypass still allows volume control? More info on the Schitt site.

And, then I recalled Bellari also has an Equalizer - along with other Bellari similar-sized devices, like a Phono Amplifier - check out the comments for more info / photos. This is powered like the Schitt Loki and this Bellari has an "Active" button - again not sure if the Loki / Bellari has passive volume control when in passive mode...

Amazon.com: Bellari Rolls EQ570 Audio Equalizer: Home Audio & Theater

Question: Loki vs eq570. how does each sound? which do you prefer?
Answer: "They sound similar and function alike. I prefer the Bellari since it has a slightly better build and its on/off switch is accessible on the front side (unlike the Loki)."
Answer: "Real difference is Loki bass boost centered around 20hz, Bellari at 60hz. Otherwise almost the same, Bellari power buttons on the front and of course gorgeous red color. No discernible quality differences in build. Bellari may be a bit heavier w/slightly thicker build material, it’s been a while since I handled Shiit and my memory may be off."

Question: How is this compared to Schiit Loki? from a performance standpoint
Answer: "For me, the low control at 60hz is better than the Loki’s at 20 hz. (Room resonance)"
Answer: "I have heard others say the two are basically the same, have no personal experience with the Schiit."

 

[Pdxwayne]

If you only have 1 device source, and volume reduction is the only function - no active gain needed, the Pre90 would be overkill for the application.

Besides the additional cost, there are the aspects of having another active signal amplifying device, you should be able to get by with a less expensive passive volume control device instead, and with good build components, there shouldn't be any effect on the audio quality.

Sorry, I don't currently use a passive volume control so I cannot give a personal use recommendation, perhaps someone else can give a recommendation for one they use?

I did a quick search on Amazon for "passive volume control", these are names I know and they look good enough to check out. And, there are more to look at one Amazon too.

Amazon.com: Schiit SYS Volume Control and 2-Input Switch: Home Audio & Theater

Amazon.com: Nobsound Mini Fully-Balanced/Single-Ended Passive Preamp; Hi-Fi Pre-Amplifier; XLR/RCA Volume Controller for Active Monitor Speakers (Black): Home Audio & Theater

Amazon.com: Nobsound High Precision Passive Preamp Volume Controller VOL Control HiFi Preamplifier ALPS (RCA&HiFi Version, Black): Home Audio & Theater

A little more searching, I remembered this gem from a review I'd read (and seen on Youtube), perhaps overkill too - it switches 4 devices, but it got good reviews:

Amazon.com: Bellari PP532 Passive Preamplifier: Electronics

Then I searched on Youtube and was reminded of the Schitt Loki Equalizer that can also be switched to passive volume control, and you might enjoy the equalizer functions too:

Schiit Audio: Audio Products Designed and Built in California - LOKI MINI+ HIGH QUALITY 4-BAND TONE CONTROL
"The Silent and Transparent Companion
Loki Mini+ transforms your system without getting in the way, or making itself known. Forget noisy, bad-sounding equalizers you may have used in the past. Loki Mini+ uses a single, discrete, current-feedback gain stage, coupled to passive LC filters for 3 bands, plus a gyrator for the bass. It also uses sealed Alps potentiometers with rational adjustment ranges to allow for fine control. Coupled with a 100% passive bypass setting, Loki Mini+ offers the transparency and flexibility you need." - Not sure if the Passive Bypass still allows volume control? More info on site, Q&A options...

And, then I recalled Bellari also has an Equlizer - along with other similar sized devices, like a Phono Amplifier - check out the comments for more info. This is powered like the Schitt Loki and this Bellari doesn't mention a passive passthrough as the Schitt Loki offers - again not sure if the Loki has passive volume control when in passive mode...

Amazon.com: Bellari Rolls EQ570 Audio Equalizer: Home Audio & Theater

Thanks for spending time searching for solutions.

Currently I am connecting xlr to amp and RCA to sub. You just made me realize that what I need is gain reduction. My amp has gain control knobs at the back. Tomorrow, I will try reducing the amp's gain so that I can use higher volume level from the DAC. Then, will see if I like the sound or not.

Thanks again!

 

[Peternz]

Please beware of that stuff on Amazon mentioned above. In terms of sound quality and build it is not on the same planet as the Pre90. I have had far higher quality passive devices in my system, and I always find they kill the energy of music when compared to a good active preamp.

 

[hmscott]

Please beware of that stuff on Amazon mentioned above. In terms of sound quality and build it is not on the same planet as the Pre90. I have had far higher quality passive devices in my system, and I always find they kill the energy of music when compared to a good active preamp.

Thanks for your use opinion, but it would help to have specifics as to the passive device(s) you used or tried to use in your system, and what the rest of the configuration specifics were for that setup.

It is easy to post non-specific negative comments without the detailed information that would make such comments useful.

Also, have you tried any of the devices I posted above as passive pre-amps or equalizers? The comments from actual verified owners of those devices are mostly positive and complimentary.

While it is "obvious" that an expensive active device like the Pre90 would provide better active results, it isn't obvious that the passive attenuation devices using ALPS potentiometers would audibly damage the audio signal.

Please do post some specifics so we know your passive reference devices.

 

[PaulD]

kill the energy of music

What units is this measured in?

 

[Peternz]

Thanks for your use opinion, but it would help to have specifics as to the passive device(s) you used or tried to use in your system, and what the rest of the configuration specifics were for that setup.

It is easy to post non-specific negative comments without the detailed information that would make such comments useful.

Also, have you tried any of the devices I posted above as passive pre-amps or equalizers? The comments from actual verified owners of those devices are mostly positive and complimentary.

While it is "obvious" that an expensive active device like the Pre90 would provide better active results, it isn't obvious that the passive attenuation devices using ALPS potentiometers would audibly damage the audio signal.

Please do post some specifics so we know your passive reference devices.

Happy to oblige. My system changes all the time, sometimes many times a day, so I will have to pass on giving you the configurations specifics. The most notable passive attenuators I have had in my system were a Goldpoint stepped attenuator in a DIY pre, a Rotel RHC-10 preamp and a LDR, light dependent resistor pre amplifier. The Goldpoint was pretty good. The Rotel looks gorgeous but the sound is laid back and a bit lazy. The LDR preamp sounded clear with a lovely reverb but also slow. None of them provided a sound I really enjoyed. The Rotel and especially the Goldpoint are much higher quality than a generic ALPS pot. No idea how the LDR pre compares to an ALPS pot.

I would not touch most of the devices from Amazon that you posted with a 10 foot pole (Schiit should be ok...). I say this based on decades of experience with audio equipment.

 

[Gyroscopics]

I found this Passive Balanced Monitor/Amp controller/preamp discussion here in ASR itself. Lots of cheaper alternatives if only volume-reduction functionality is needed.

https://www.audiosciencereview.com/...balanced-monitor-amp-controller-preamp.11891/

 

[DHT 845]

The simple way to use DAC digital attenuator in it's upper range is to use simple attenuator on RCA / XLR.
Other way is to make an interconnect with voltage divider (2 resistors) set to some fixed attenuation.

 

[gvl]

These passives can potentially create more problems than they solve. I'd use one only if my DAC had fixed output that was too "hot" for my integrated amp.