Review and Measurements of Monoprice Portable Amp and DAC with THX

[Gus141]

I’m enjoying the sound coming from this DAC/Amp as well. Granted, my headphones are not very demanding: Sony MDR-1A, Sony MDR-1AM2, and Sony MDR-Z1R. Since I bought this DAC for portable use, I rarely use it with the much larger Z1R cans. The volume is way more than adequate for the highly efficient 1A and 1AM2 headphones.

Which brings me to my question: @amirm , based on measurements, does this DAC perform better at higher gain levels and thus benefit from an iFi IEMatch or EarBuddy with my high-efficiency headphones?

I use an IEMatch or Earbuddy on other DACs with my high-efficiency headphones to avoid some issues at lower gain levels (e.g., on the Topping NX4 DSD with low gain set, I use the IEMatch on the “high” sensitivity setting with the Sony MDR-1A (24 Ohm) headphones due to audible channel imbalance at low volume levels; with the IEMatch, I can operate at 12 o’clock on the volume knob, getting past the low-gain problem area and still have some headroom).

Cheers
Gus

 

[amirm]

Which brings me to my question: @amirm , based on measurements, does this DAC perform better at higher gain levels and thus benefit from an iFi IEMatch or EarBuddy with my high-efficiency headphones?

Those devices force the amp to run at much higher power levels and hence distortion. So I would not use them unless you have to.

 

[Gus141]

Thanks @amirm for the reply. In this case, I don’t see (or hear) a need to use them with the Monoprice Portable so I’ll operate without.

For the NX4 DSD, I definately benefit from the iFi IEMatch or EarBuddy to get past the channel imbalance at low levels.

 

[Gus141]

I really like the sound coming this Monoprice Monolith Portable THX DAC/Amp in combination with my headphones.

For others considering this DAC/Amp, here are some additional impressions of mine after a couple of weeks of use with the following headphones: Sony MDR-1A, Sony MDR-1AM2, Sony MDR-Z1R (yes, I like the “Sony House” sound).

I don’t use any of the bells and whistles: no EQ, no compression, no DIRAC. I thought I’d use the EQ with my Z1R headphones (I use all 5 PEQ bands on the RME ADI-2 DAC to dial out some of the problems inherent with my Z1Rs) but honestly I haven’t bothered yet with this DAC because I prefer to use my more portable headphones with this portable DAC, and those headphones sound great without EQ.

I personally disliked the sound with DIRAC-on and I’ll never use it. I sounds too artificial to me.

I really like having a display. Setting the same volume level for certain music/song/headphone combinations is super easy with a display. I also like to confirm, when streaming with Qobuz, that the Qobuz stream is the same as the adveritsed hi-res quality (some Qobuz songs are advertised as Hi-Res but only stream in Redbook, and you need to purchase the song to get the Hi-Res). The sample frequency rate in the display helps with that. There is no bit depth shown in the display though: I think there may have been a firmware where the bit depth was shown, because the picture of the DAC on the box cover of the packaging shows a display that listed both frequency rate and bit depth (if you search Google images you can find that picture as part of the early promotional material showing “192KHz 24bit USB IN”).

Battery life is great; about double what I get with the Topping NX4 DSD (but I operate at a higher gain on the NX4 with an artificial load added [the iFi IEMatch or EarBuddy]).

The volume control is great and smooth, but a little over sensitive, so don’t put it in your pocket unless you want unexpected volume increases/decreases.

The sound quality to me is excellent but doesn’t completely trump everything. I like my NX4 DSD with my Sony MDR-1AM2 (and an iFi EarBuddy), but I like the Monoprice Portable THX DAC with the older Sony MDR-1A headphones. My order or preference for portable use is:

1. Monoprice Monolith THX Portable w/ Sony MDR-1A
2. Topping NX4 DSD w/ Sony MDR-1AM2 (and iFi EarBuddy)
3. Topping NX4 DSD w/ Sony MDR-1A (and iFi IEMatch on “High”)

None of the portable DAC configurations I have tried sound as good as my Sony MDR-Z1R headphones through an RME ADI-2 DAC (with some PEQ to realize the latest Harmon curve). But for portable use, they are great. The Topping costs a lot less for the same performance. If you need the display and a longer battery go with the Monoprice Monolith THX Portable, otherwise, I recommend the NX4 DSD for portable use. For desktop use, I’m loving the RME ADI-2 DAC.

Cheers
Gus

 

[Mattrazol]

Hello everyone! I'm planning to buy a NX4 and use it with my IEMs. I currently have a pair of BGVP DM6 which have an impedance of 20 ohms. I'm also planning to get an EarBuddy / IEMatch to compensate the channel unbalance output that has been reported by @amirm . So I was wondering which of the two will best fit my setup, because I noticed that even though the EarBuddy doesn't have the switch to change sensitivity, it has an higher attenuation compared to the IEMatch, specifically -16dB compared to the -12dB of the IEMatch in "High sensitivity" mode. In fact by looking at your usage (@Gus141) of both of them I noticed that you've used the EarBuddy to match the higher sensible MDR-1AM2 (22 ohms?) therefore I can conclude that the EarBuddy might be a better choice for my specific configuration? What are your thoughts on this @amirm @Gus141?

Thanks in advance for your help.

 

[Gus141]

Hello everyone! I'm planning to buy a NX4 and use it with my IEMs. I currently have a pair of BGVP DM6 which have an impedance of 20 ohms. I'm also planning to get an EarBuddy / IEMatch to compensate the channel unbalance output that has been reported by @amirm . So I was wondering which of the two will best fit my setup, because I noticed that even though the EarBuddy doesn't have the switch to change sensitivity, it has an higher attenuation compared to the IEMatch, specifically -16dB compared to the -12dB of the IEMatch in "High sensitivity" mode. In fact by looking at your usage (@Gus141) of both of them I noticed that you've used the EarBuddy to match the higher sensible MDR-1AM2 (22 ohms?) therefore I can conclude that the EarBuddy might be a better choice for my specific configuration? What are your thoughts on this @amirm @Gus141?

Thanks in advance for your help.

I stopped using the EarBuddy and IEMatch. At first I was convinced I needed them to ensure I didn’t experience channel imbalance with the NX4 DSD. But after reading Amir’s reply to me above (“Those devices force the amp to run at much higher power levels and hence distortion. So I would not use them unless you have to.”) I decided to try without them for a week. I found that most of the time I operated the DAC at high enough gain settings that I didn’t notice any channel imbalance and that it was probably better to not over tax the DAC if I didn’t have to.

My recommendation is to try the NX4 DSD without the EarBuddy. If you can’t sense an imbalance at your preferred volume settings then there’s no need for it. You can always buy it later if you have to.

I’m glad I have one less cable/dongle to carry around now. I should probably edit the statements I made above about needing the EarBuddy/IEMatch, but at the time (I was trying to listen at low levels to see if I could hear an imbalance) those were accurate statements, so I’ll leave as is for others to read in case they listen at low volumes most of the time. And yes, I chose the EarBuddy for the MDR-1AM2 (16 ohms, by the way) because it was in the middle of the options: IEMatch -12dB [high setting], EarBuddy -16dB, IEMatch -24dB [ultra setting]. For the MDR-1A (24 ohms) I chose the IEMatch’s -12db “high” setting.

Cheers
Gus

 

[pwjazz]

I started my testing Sennheiser HD-650. Unfortunately I was easily able to push the unit into clipping distortion with my standard test tracks

How loud do you listen @amirm? 36mW should drive the HD650 to over 110dB. Is there something else going on here other than just total power?

 

[amirm]

How loud do you listen @amirm? 36mW should drive the HD650 to over 110dB. Is there something else going on here other than just total power?

I put little value on those dB numbers. Also, for testing I push the devices. I turn up the volume to as much as I can tolerate.

 

[Teroz]

I can produce the hiss to but only when connected to PC with USB and charge the unit at same time from PC. When i pull the charger USB cable out the noise goes away. My unit is dead silent no hiss or anything.
Much better in sound quality than my AUNE x1s. much more analytic and clearer. Also soundstage and instrument separation is noticeable better.
I just like this much better than any portable DAC/AMP iw heard before, easily. Better than iFi Micro iDSD Black Label or even Chord Mojo.

Enjoying it even with my HD800 and specially with Audeze SINE:

 

[Jorj]

I just like this much better than any portable DAC/AMP iw heard before, easily. Better than iFi Micro iDSD Black Label or even Chord Mojo.

Hopefully your unit does not have the issues that mine did. There is no way I'll trust my hearing to a Monoprice audio component ever again. Even if they have sorted out the quality issues, the only real selling point for me was the Dirac Sensaround, which turned out to be a whole lotta nothingsauce. Without that, it was just another portable DAC\amp, and to be honest, I've never been able to tell the difference between my Mojo and other up-market portables in filter & level-matched listening.

 

[Grattle]

Has anyone found a lightning -> micro usb cable for this amp that doesn’t require the camera connection kit?

 

[Sinquito]

Hello everyone! I'm planning to buy a NX4 and use it with my IEMs. I currently have a pair of BGVP DM6 which have an impedance of 20 ohms. I'm also planning to get an EarBuddy / IEMatch to compensate the channel unbalance output that has been reported by @amirm . So I was wondering which of the two will best fit my setup, because I noticed that even though the EarBuddy doesn't have the switch to change sensitivity, it has an higher attenuation compared to the IEMatch, specifically -16dB compared to the -12dB of the IEMatch in "High sensitivity" mode. In fact by looking at your usage (@Gus141) of both of them I noticed that you've used the EarBuddy to match the higher sensible MDR-1AM2 (22 ohms?) therefore I can conclude that the EarBuddy might be a better choice for my specific configuration? What are your thoughts on this @amirm @Gus141?

Thanks in advance for your help.

I have the NX4 DSD, no imbalance issues using IEMs such Ety ER4SR and ER2XR, Sony EX-800ST, AKG N40, this is on low gain. I actually didn't understand the purpose of the IEMMatch if high gain was needed, is like adding and then subtracting, you end up with pretty much the same number. For IEMs the pot is usually set at 10 o'clock, for over ears like HD600, 11:30 to 12 o'clock is fine.

 

[Mike Arnopol]

Interesting. I design and manufacture very high end speakers for bass players. I've toured professionally as a bassist for all of my life. I've played and recorded with major jazz artists. (2 Grammy winning recordings}. Many might know me for my work with Patricia Barber.
I just mention this because I have really good ears. I was on the Beta testing team for Jerry Harvey's JH13's ten years ago. Recently i've gotten back into listening to high end IEM's. I'm not rich, so I sold one of my electric basses and bought
Audeze LCD i3
Tansio Mirai Zodiac
Zorloo Ztella
Xduoo o5 plus (with the Burson chip)
Monoprice Monolith THX AAA portable
I love everything I got. Funny thing is--that I prefer the Monolith over the other 2. Better soundstage, more accurate placement in the soundstage. I prefer the tonal balance.
But I guess it doesn't measure well. One thing that I've learned is that the sound and listening experience is much more complex than the measurements. Two DAC/AMPs may measure near the same but sound and present the music in very different ways. In some ways, other speakers may measure better than mine. But--the feedback that I get--is that they feel and perform better than any others. I really feel--that while important--the measurements done only indicate a small part of the listening experience. I'm sure that the Xduoo measures better--but I vastly prefer listening the the Monolith. I love what you're doing here but I worry that some pieces that provide spectacular sound and listening experience might get overlooked.

 

[Jorj]

I just mention this because I have really good ears. I was on the Beta testing team for Jerry Harvey's JH13's ten years ago. Recently i've gotten back into listening to high end IEM's.
<snip>
But I guess it doesn't measure well. One thing that I've learned is that the sound and listening experience is much more complex than the measurements.
<snip>
I love what you're doing here but I worry that some pieces that provide spectacular sound and listening experience might get overlooked.

Welcome! As a new member, I'll go easy. The point of this site is to provide a welcome dose of objective data to an industry that has been overrun by subjective nonsense. Keep that in mind, and remember we're all human, with preferences, biases. We are all learning.

I bought one of these and had terrible luck with it. Even had it replaced under warranty, and it was still awful. Nothing to to with measurements, the UI was so flaky and blasted my ears for no reason.

Remember also that the measurements weren't audibly bad. The features the device advertised did not work as promised, and there are better values with regards to SQ. If you like it, that is wonderful. No one here should disrespect that, and we all welcome your participation and thoughts. Be careful to use the proper humility and disclaimers when making subjective statements, and we'll all get along just fine.

 

[c69k]

Hi, I have Topping NX4 DSD and Monolith THX AAA Portable. Have been using NX4 DSD for 6 months, but after extensive reading about Monolith I bought it, and keep NX4 DSD as spare. I like deep bass a lot (drill rap mostly these days), but I prefer detailed, cold and analytical bass and sub-bass (not warm and boomy).

After trying Monolith, it is definitely an upgrade to NX4 regarding overall sound. I use it with Sony EX800ST (3Hz-20000Hz) IEMs. The sub-bass with Monolyth goes definitely deeper and cleaner, it is not boomy as with NX4 DSD+bass boost.

Another thing is that NX4 DSD has bass roll-off under 20Hz, whereas Monolyth is able to output 1Hz - 20000Hz. At the same time the detail in frequencies above bass is just insane compared to NX4 DSD, I actually started enjoying highs since Monolith as they are not cutting-in my eardrums as with NX4.

I have to agree that it all really depends on IEMs you use, Sony EX800ST can take 500mW, so the deep sub-bass under 20 Hz suddently sounds and also FEELS that it is there.

Battery stops charging automatically when full.

Please ask if you need any A/B.


p.s.

There is only one negative:

The volume control knob is really easy to turn in my pocket, so I have used a very thin black rubber band around the knob, all is 'safe' now.

 

[Tortie]

Wouldn't it depend on what phone you have? If you have an LG phone with their quad DAC then you wouldn't be getting better performance with the Monoprice unit. I use an external amp with my LG G7 because it gives me more power and a rotary volume control. That improves the listening experience for me.

I have an LG phone with a Quad DAC as well and for the past few months I was using it with a FiiO A5. The combination was quite good but not perfect. I recently broke my A5 and now I'm back to just listening via the LG headphone jack. I'm curious what portable amp you used or would recommend to purchase today if you were starting over. Most manufactures such as iBasso and FiiO have stopped making dedicated portable headphone amps. Aune (B1s) and Topping (NX3s) are two examples of currently available dedicated portable amps. The industry has since moved to AIO devices that integrate DAC and amplification which sucks when you only need amplification.

 

[m8o]

Tho the various THX modules do usually go hand in had with top-tier power output, their tech is not solely about brute force output power (POW-WAAAR, as Jeremy Clarkson loves to scream -hehe ). A large part of its appeal is the touted "feed forward" circuitry that supposedly nullifies switching distortion of a class AB amplifier. Resulting in more fluidity / smoothness when its cranking along.

To any owners or folks who spent extended time with this, any comments in this regard? The power requirements of the iem I would use this with (the new Audeze Euclid) are mostly achieved by this. But I'd want to know first that what the feed-forward tech of the THX amp is supposed to provide us is, simply put, here. I do realize I'm asking about a very subjective aspect of this amp's capability on a forum that eschews subjectivity.

 

[Pernas]

Is this the only available product which carries the following capabilities compared to other portable HP amps?

* Analog and TOS-link inputs
* A "good" EQ which also works for all inputs and not only the DAC
* "App-less" controls is a must for autonomous use

The only thing it lacks is separate EQ for L/R - I noticed that I need that nowadays after some analysis through Samsung adapt sound

/Per

 

[Bluland135]

Is it possible to only use the amp portion of this unit? Would running a 3.5mm analog out from another DAP into this unit's line-in bypass the DAC section and only use the amp function?

 

[Teroz]

Is it possible to only use the amp portion of this unit? Would running a 3.5mm analog out from another DAP into this unit's line-in bypass the DAC section and only use the amp function?

No, its not possible. DAC is involved all times.