Preview: Monolith by Monoprice Desktop THX Headphone Amp & DAC

[amirm]

It starts with poor project management seeing the condition of the product I received.

 

[FireLion]

It starts with poor project management seeing the condition of the product I received.

Absolutely and whoever is in charge of this amp probably messed up on cutting a corner on the adapter where he could have spent $5 instead of $2.

What I don't like about Monolith is there is no face or team we can identify with. It just some mysterious team who liases with Chinese OEMs and occasionally Alex Cavalli.

For instance the m1060c had the potential to be tuned into a great sounding headphone but it for some reason has a piece of bendy sheet metal for a headband.
ZeosPantera supposedly told them over a year ago to change it and they said it was in the works but alas no improved tuning or comfort. Gotta love little loose foam discs as damping.

Edit: Still got the over temperature protection. I prob have a faulty unit but at least you can use a 16v adapter.

 

[mgmate]

I must say that I have no issues with the power adapter up to now.

After succesfully (it was very easy) grounding the case, the buzz issue with very low impedance IEMS was fade away for good.

I agree also with Amir. Receiving a product with a beta firmware is not a good sign of proper tested unit. Probably the last minute change in design delay the project and increase the costs, but this does not justify it.

I must say on the other hand that I am enjoying it a lot. With the Senns 660s on XLR balanced is a great combo and it's very good sound surprise me every day.

Regards,

Manuel.

 

[Son-of-Lux]

I must say that I have no issues with the power adapter up to now.

After succesfully (it was very easy) grounding the case, the buzz issue with very low impedance IEMS was fade away for good.

I agree also with Amir. Receiving a product with a beta firmware is not a good sign of proper tested unit. Probably the last minute change in design delay the project and increase the costs, but this does not justify it.

I must say on the other hand that I am enjoying it a lot. With the Senns 660s on XLR balanced is a great combo and it's very good sound surprise me every day.

Regards,

Manuel.

I agree. I personally have had absolutely no problems and I've been happy with the performance, but I can understand how frustrated people can be with all of the issues they've been having.

Hopefully, now that Zeos has praised it, there will be more available and we can get someone to send a unit to Amir

 

[antdroid]

I can send my unit if it'll be tested and in a relatively timely manner. Let me know.

 

[mgmate]

It will be great for the forum!!!!!!

Hope @Amir answer you to have more competition in the DAC/AMP section with the relative older THX 788 amplifier.

Is it in the last firmware 1.03?

Regards

 

[BullBuchanan]

I loled fucking hard when I see ad8397. Finally, I now know that thx aaa technology is whole marketing bullshit. It might not be bad and in fact it's quite ok engineering but holy fuck.
Same shit with thx789. Let me say something, jds atom, not even great in my standard, destroys 788 here. 788 and 789 sounds like just tiny difference but omg, the difference in of current capability and power dissipation ability is night and day. I was already sketchy when I saw opa564. Now everything is clear. Of course I would have known this because there is no way that someone never did semiconductor engineering/design suddenly shits on everybody on the market(ad and ti or other discrete output designs). And if they did it, there is no way to sell this cheap(also thx 789)
However, this has nothing to do with the performance or engineering. It also proves my point, amplifiers are really easy to design, especially for headphones, and more especially when you're not using discrete design. Any good electrical engineer can design up to this level of performance for headphone amplifier. Also properly engineered ic based amplifier can be great and be better than most of the non-properly engineered shit.
Sure the 888 and the power amp are great but those are like thousands of dollars. Also 888 is not even that superior still. Again it's just properly engineered product. Nothing to hype about.

It's something to hype about when no one else has done it. Are you suggesting there's a better amp at the same pricepoint as the THX 789? Or even one under $1k?

 

[antdroid]

It will be great for the forum!!!!!!

Hope @Amir answer you to have more competition in the DAC/AMP section with the relative older THX 788 amplifier.

Is it in the last firmware 1.03?

Regards

Yes it's updated.

 

[amirm]

I can send my unit if it'll be tested and in a relatively timely manner. Let me know.

Thanks. Let's do it then.

 

[amorr01]

This is an early look of the Monolith by Monoprice Desktop Headphone Amplifier and DAC with THX amplification technology. The unit was kindly purchased by a forum member and drop shipped to me. And that is where the trouble began but more on that later. The Monoprice THX amp and DAC retails for USD $480.

The Monoprice THX amp and DAC has the same design language of other "monolith" units which translates to a serious look. There is brushed metal on front and very shiny and glossy enclosure which instantly shows fingerprints:

View attachment 18096

Let's backtrack a bit. I have ordered three products from monoprice. The first one never came and I only found out about it a few months later. I then ordered two other products from them both of which were sent to a remote neighbor. Their street and house number are one digit off from us. Hard to imagine how someone could be this bad at reading addresses yet be in delivery business.

Worried that this unit would also face the same fate, I contacted the carrier and monoprice. With the latter, I read them the riot act for sending the last shipments to wrong address. No response came back. The carrier sent me a form response a couple of days later saying "we will get back to you." Well, they didn't and today got notification that the package was delivered at the front door. Searched everywhere and no sign. Called the carrier and they started to investigate. A few phone calls later and then neighbor calls and says the package is once again delivered to her. Thankfully it was double boxed or it would have been soaked in the rain.

I unpack the unit and find no manual of any type -- just a code to put in online to find it. I know we have moved away from paper but come on, for a $500 device, I expect a little cheat sheet on how to power the unit on. Yes, how to power it. Look at the front panel: there is no indication of how you turn it on! Fumbling I hit the enter button and I see the monoprice log and the unit lights up.

I hook up a USB cable to it, select that input and run a quick dashboard test. I get to SINAD of 107 in best case scenario. Where is that output you ask? Well, I usually run a few quick tests before doing a formal review and I don't save those. I went on to test output power and with 300 ohm, and single-ended, I get half the rated power before clipping (and less than Topping DX3 Pro). I then test 33 ohm, and here I get about a watt of power which is decent.

I thought I test the amplifier section by itself so I hook up a set of analog cables to its inputs. In the midst of switching things around, the protection circuit kicks in which is fine. But on the second instance this happened, the unit shut itself off. Hmmm. This is never a good sign. I turn it back on and now it is acting crazy. Menus work but changing the volume causes it to update the new value 0.5 dB every few seconds! Changing inputs no longer works as you see from the stuck "RCA Line" in the above picture. Factory reset does nothing.

There is an about menu so I selected that and see this:

View attachment 18097

0.82 beta? Really? With all the delay in production of this unit they couldn't finish the firmware?

Seeing the dismal usability of the firmware, my suggestion is for them to throw it all out and start over. It is maddening to navigate. Why isn't there a single button press for changing inputs? Once you go into menus, the rotary volume control goes through different options. But when you go into settings, the enter button does that! Why or why? Between it crapping out and poor usability I am tempted to throw it into the bay. But then it is not mine so I better not do that.

And oh, the purpose of messing with it was that I was getting the two channels completely out of phase with each other when feeding it analog input! I ran out of options with the thing breaking before trying everything. I doubt the issue is at my end though.

Back to functionality, any desktop product in this range should have a remote control for volume so that you can use it in your equipment rack.

Conclusions
I was all excited to get this review out quickly for you all. But the company didn't allow it. Between poor delivery, customer service, firmware functionality and reliability, I am not sure I have any motivation left to test the product anymore. And can you imagine my mood if they replace this and it goes to the neighbor again? She was ready to shoot me had it not been for the joyous holiday mood!

The bit of performance that I did measure was good but not exceptional. At nearly $500, that is not acceptable. You can get excellent $100 DACs and pair them with the Massdrop THX 789 or JDS Labs Atom and be in business for less than what this unit costs. And they would be a lot easier to use.

Anyway, I feel bad for the owner who actually lives in Europe and ordered this just for the good of the community. I think I am going to ask him to get a refund instead of replacement.

My suggestion is to buy the Massdrop THX, JDS Labs Atom or Neurochrome HP-1 if you need high performance headphone amplification and a DAC of your choice. Otherwise, there are excellent all-in-one choices like Topping DX3 Pro which cost less than half of this unit.

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I got nothing from this review.

 

[amirm]

I got nothing from this review.

Maybe because it was a preview and not a review?

 

[FireLion]

Wanted to report back i re-terminated my cable with a new xlr with a fresh cut on the cables and all seems to be good now. I individually put heatshrink on each pole and have been running 10db higher without any issues. Must have been a break in a cable somewhere.

Well at least ye know a 16v will work.

 

[antdroid]

Package has been delivered. It was nice to meet @amirm in person!

 

[amirm]

Package has been delivered. It was nice to meet @amirm in person!

Was nice to finally meet you too. I will see if I can get it reviewed soon.

 

[deafenears]

Was nice to finally meet you too. I will see if I can get it reviewed soon.

Should have just brought along your APx555, hook it up at a local cafe, and test it then and there

 

[mgmate]

Hi Amir, Did you have any chance of testing it?

Regards and many thanks for your great job!

Manuel.

 

[Veri]

Hi Amir, Did you have any chance of testing it?

Regards and many thanks for your great job!

Manuel.

I suppose you missed the full review?

https://www.audiosciencereview.com/...ements-of-monoprice-thx-desktop-dac-amp.7483/

 

[deafenears]

Maybe the front page should be updated with a link to the actual review post/thread.

 

[mgmate]

Thanks, I was expecting the review in this thread!!

Thanks Amir!! and Veri to point me to the new review!-

 

[GGroch]

Its back! Now $600 with ESS ES9820Q and ES9038Q2M chips instead of AKM. It appears most of the features are the same. I owned one of the AKM versions for a while and enjoyed it. Lots of electronic switches to twiddle.