This is a subjective review and comparison of the SMSL AD18 integrated DAC/amplifier. This item was purchased from a private party. I do not have any measurement implements so what follows are my opinions. I will try to be as impartial as I can.
I am still surprised by how much these manufacturers can cram into such a petite package. Despite being so small the display is fairly useful and easy to read (at least the center is). The ability to change the display color and brightness is a nice touch as well. The panel appears to be of the TFT variety, so unless you’re looking at the display straight on the display image quality suffers due to aggressive contrast changes. As a consequence I typically have the brightness set to level 3 (it goes up to 9) most of the time.
Connectivity is diverse enough for a desktop solution. The only full size input is “optical 2”. A bit curious that the mini optical is in the same port as the subwoofer output as well as the coaxial SPDIF input. I’m not fond of mini jacks, especially not 3.5mm triple purpose ones. Hopefully one SPDIF optical input is sufficient for those of you who wish to use the subwoofer output. The AD18 also has a single 3.5mm AUX input as well as a Micro USB to function as a desktop DAC. The binding posts are uncomfortably tiny and feel very cheap. They are all but identical to the ones found on the Topping PA3 I reviewed last month. They are very close together, so be careful with banana plugs or bare wire. I made sure to strip just enough insulation from speaker wire to get contact.
Connecting power for the first time there was a significant spark between the unit and the AD18’s DC inlet and the terminal end. When setting up for this review it happened again. It may be harmless, but from now on I will run all wiring to a switched off power strip until I'm ready to give it power.
While on the topic of power, the PSU appears to be grounded. The PA3 came with a larger Topping branded PSU, but no ground. The AC mains power cord that came with the Topping was also quite thin. Both the AC mains cable and DC cable with the SMSL appear to have more insulation.
Comparing some of the features of the AD18 with the DX3 Pro and it’s immediately apparent the AD18 is meant to be a crowd pleaser. The AD18 includes bass and treble adjustments as well as several preset EQ modes. I’ve not given much attention to these settings other than to acknowledge their existence, however each EQ setting appears to have a unique sound. The Topping DX3 Pro has different output filters but discerning audible differences between them is a challenge for my ears.
The AD18 and DX3 Pro both feature Bluetooth. The AD18 utilizes 4.2 where the DX3 Pro utilizes 5 and allows APTX if you can take advantage of it. I take issue with the DX3 Pro because the Bluetooth receiver remains active and will still paired with my iPhone even while in standby. I don’t know if Topping has a firmware patch for this, but they should. The SMSL AD18 gains points for not having a needy Bluetooth receiver.
Since my last review I made a few changes. I’ll be using Boston Acoustics VR-M60 bookshelf monitors, which were compared favorably to Paradigm’s Studio 20 (whichever version was available around that time). I decided that it was too laborious to cannibalize my main entertainment system for doing these tests. The Vandersteen’s are also pretty laid back speakers, where the Boston’s are much more forward. That should lend them to be more revealing of upstream differences.
As before mentioned, I do not have any measurement equipment, not even an SPL meter. I did my best to level match by ear and I used a Niles speaker/amp switch which I operated during this comparison. Needless to say, this comparison was not blind.
I started my test using an Apple TV 3 feeding the DX3 Pro’s optical input. I connected two male to dual female y-adaptors to the outputs and set the DX3 Pro’s output to variable. One pair of RCA cables connected to the Topping PA3 and a RCA-3.5mm adaptor to the SMSL AD18’s AUX input.
After level matching I began the comparison with Rebecca Pidgeon’s “Spanish Harlem” from Chesky’s Demo program. The track has fine detail the vocals are dynamic. Immediately I encountered a problem, the AD18’s right channel had a high pitched ringing sound. In order to match the PA3’s max gain the volume on the AD18 was set to 52, just 8 clicks from its max. I considered this could be a fault of the input or some kind of interference or noise from the power supply. In order to see if I could replicate the noise with another source I pulled out my CD player. Making no other changes other than connecting the CD player in lieu of the Apple TV via optical, even with the same cable, the noise went away. Later on in my testing I tried to reconnect the Apple TV, the noise came back. Bummer, the music I had planned to use for the comparison I could not use.
Relying on the relics of past, round discs with holes in the center, with a silver colored surface that is read by bouncing light off of it. Dave Matthews Band’s “Some Devil” has some rich sounding instrumentation though Dave’s slight raspiness can sound harsh at times. I skipped around the album while instantaneously switching between the AD18 and PA3 and was unable to tell the two apart. I made the decision to swap out the PA3 for the B&K 125.2 and still, indiscernible.
Just played track #1 on this album. The drums are visceral and loud. The AD18 handled it surprisingly well, but I pressed it little far and got some clipping. No big surprise, the B&K powered through this track without any signs of stress, but that’s not really fair to the AD18.
Norah Jones, what Hi-Fi shop doesn’t have this CD somewhere on it’s premises? Another dynamic voice like Rebecca above, I chose Nightingale to make this comparison. Well, guess what? Boring comparison, no discernible difference between the AD18 and the B&K for my part.
I connected the Apple TV to the AD18’s optical input briefly and there was no high pitched ringing sound. I also briefly connected the CD player’s coaxial output to the DX3 Pro which was feeding the PA3 at the time, and the optical output of the same CD player to the AD18. After level matching I was unable to discern audible differences.
In not so dramatic conclusion, it appears to be a good amp. Unless you have a golden ear or difficult to drive speakers this could be a good DAC/amp to use in an office or small room. I wouldn’t use it to crank bass heavy EDM or rap, but don’t let that fool you into thinking it cannot play as loud as you would like 98% of the time. You can save space and money by getting a product like this and putting most of your budget toward speakers, room treatments, or active EQ implementation which stand to benefit your listening far more than getting a DAC with 20dB better SINAD.
Edit: If anyone should have anything they'd like to add or critique I'd very much like to hear your thoughts.
I am still surprised by how much these manufacturers can cram into such a petite package. Despite being so small the display is fairly useful and easy to read (at least the center is). The ability to change the display color and brightness is a nice touch as well. The panel appears to be of the TFT variety, so unless you’re looking at the display straight on the display image quality suffers due to aggressive contrast changes. As a consequence I typically have the brightness set to level 3 (it goes up to 9) most of the time.
Connectivity is diverse enough for a desktop solution. The only full size input is “optical 2”. A bit curious that the mini optical is in the same port as the subwoofer output as well as the coaxial SPDIF input. I’m not fond of mini jacks, especially not 3.5mm triple purpose ones. Hopefully one SPDIF optical input is sufficient for those of you who wish to use the subwoofer output. The AD18 also has a single 3.5mm AUX input as well as a Micro USB to function as a desktop DAC. The binding posts are uncomfortably tiny and feel very cheap. They are all but identical to the ones found on the Topping PA3 I reviewed last month. They are very close together, so be careful with banana plugs or bare wire. I made sure to strip just enough insulation from speaker wire to get contact.
Connecting power for the first time there was a significant spark between the unit and the AD18’s DC inlet and the terminal end. When setting up for this review it happened again. It may be harmless, but from now on I will run all wiring to a switched off power strip until I'm ready to give it power.
While on the topic of power, the PSU appears to be grounded. The PA3 came with a larger Topping branded PSU, but no ground. The AC mains power cord that came with the Topping was also quite thin. Both the AC mains cable and DC cable with the SMSL appear to have more insulation.
Comparing some of the features of the AD18 with the DX3 Pro and it’s immediately apparent the AD18 is meant to be a crowd pleaser. The AD18 includes bass and treble adjustments as well as several preset EQ modes. I’ve not given much attention to these settings other than to acknowledge their existence, however each EQ setting appears to have a unique sound. The Topping DX3 Pro has different output filters but discerning audible differences between them is a challenge for my ears.
The AD18 and DX3 Pro both feature Bluetooth. The AD18 utilizes 4.2 where the DX3 Pro utilizes 5 and allows APTX if you can take advantage of it. I take issue with the DX3 Pro because the Bluetooth receiver remains active and will still paired with my iPhone even while in standby. I don’t know if Topping has a firmware patch for this, but they should. The SMSL AD18 gains points for not having a needy Bluetooth receiver.
Since my last review I made a few changes. I’ll be using Boston Acoustics VR-M60 bookshelf monitors, which were compared favorably to Paradigm’s Studio 20 (whichever version was available around that time). I decided that it was too laborious to cannibalize my main entertainment system for doing these tests. The Vandersteen’s are also pretty laid back speakers, where the Boston’s are much more forward. That should lend them to be more revealing of upstream differences.
As before mentioned, I do not have any measurement equipment, not even an SPL meter. I did my best to level match by ear and I used a Niles speaker/amp switch which I operated during this comparison. Needless to say, this comparison was not blind.
I started my test using an Apple TV 3 feeding the DX3 Pro’s optical input. I connected two male to dual female y-adaptors to the outputs and set the DX3 Pro’s output to variable. One pair of RCA cables connected to the Topping PA3 and a RCA-3.5mm adaptor to the SMSL AD18’s AUX input.
After level matching I began the comparison with Rebecca Pidgeon’s “Spanish Harlem” from Chesky’s Demo program. The track has fine detail the vocals are dynamic. Immediately I encountered a problem, the AD18’s right channel had a high pitched ringing sound. In order to match the PA3’s max gain the volume on the AD18 was set to 52, just 8 clicks from its max. I considered this could be a fault of the input or some kind of interference or noise from the power supply. In order to see if I could replicate the noise with another source I pulled out my CD player. Making no other changes other than connecting the CD player in lieu of the Apple TV via optical, even with the same cable, the noise went away. Later on in my testing I tried to reconnect the Apple TV, the noise came back. Bummer, the music I had planned to use for the comparison I could not use.
Relying on the relics of past, round discs with holes in the center, with a silver colored surface that is read by bouncing light off of it. Dave Matthews Band’s “Some Devil” has some rich sounding instrumentation though Dave’s slight raspiness can sound harsh at times. I skipped around the album while instantaneously switching between the AD18 and PA3 and was unable to tell the two apart. I made the decision to swap out the PA3 for the B&K 125.2 and still, indiscernible.
Just played track #1 on this album. The drums are visceral and loud. The AD18 handled it surprisingly well, but I pressed it little far and got some clipping. No big surprise, the B&K powered through this track without any signs of stress, but that’s not really fair to the AD18.
Norah Jones, what Hi-Fi shop doesn’t have this CD somewhere on it’s premises? Another dynamic voice like Rebecca above, I chose Nightingale to make this comparison. Well, guess what? Boring comparison, no discernible difference between the AD18 and the B&K for my part.
I connected the Apple TV to the AD18’s optical input briefly and there was no high pitched ringing sound. I also briefly connected the CD player’s coaxial output to the DX3 Pro which was feeding the PA3 at the time, and the optical output of the same CD player to the AD18. After level matching I was unable to discern audible differences.
In not so dramatic conclusion, it appears to be a good amp. Unless you have a golden ear or difficult to drive speakers this could be a good DAC/amp to use in an office or small room. I wouldn’t use it to crank bass heavy EDM or rap, but don’t let that fool you into thinking it cannot play as loud as you would like 98% of the time. You can save space and money by getting a product like this and putting most of your budget toward speakers, room treatments, or active EQ implementation which stand to benefit your listening far more than getting a DAC with 20dB better SINAD.
Edit: If anyone should have anything they'd like to add or critique I'd very much like to hear your thoughts.
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