PS Audio Sprout100 Review: Sprouting Passion

Introduction

In the audio world, PS Audio brand should not be a stranger. The brand is typically tied with high-end audio products, with price tags in the 4 to 5 digits range. It is therefore refreshing to know that the brains at PS Audio have conceived an entry-level budget product with their high-end knowledge and experience. Costing $699 USD, the Sprout100 may equate to about a month of room rent for college/university students. But, it is still a very cheap alternative to their other products. As the company says on their website, this is their “vision of a simple, elegant means of playing music at home.”

In this review, we shall see how their offering is still relevant 2 years on from their release. This is also their second iteration at such a product, with their first one being just named the Sprout. An easy way to remember is this naming reflects an increase in the amplifier power from 50 watts in the previous model to 100 watts at 4 ohms max.

Disclosure

For this review, PS Audio’s only part in this review is the loaning of the Sprout100 as well as seeing the review before release for fact-checking. In no way have they influenced my evaluation process. All words and impressions are my own words. I thank PS Audio for sending me out a review sample for evaluation.

Specifications

Physical
Unit Weight	2.9 lbs [1.3 kg]
Unit Dimensions	Width 6.2″, Height 1.9″, Depth 8.2″ (chassis only, not including knobs) or 9.2” (including connectors and knobs)
Shipping Weight	5lbs [2.2 kg]
Shipping Dimensions	Width 10.5″, Height 5″, Depth 14″
Power requirements
Voltage Options	100-240 VAC, 50-60Hz, Auto-Detect
Power Consumption	280W Maximum
Phono Audio Input
Connector	1 Stereo Pair, Phono RCA
Cartridge type	Moving Magnet
Cartridge Output	3mV-10mV (5mV recommended)
Cartridge Loading	47KΩ (100pF)
EQ Type	RIAA
Gain	+40dB
S/N ratio	>84dB A-weighted (analog output)
Analog Audio Inputs
Connector	1 Stereo Pair, Line Level RCA
Maximum Input level	2.1VRMS (+6.44dBV)
Input impedance	10KΩ
Analog Audio Output
Connector	1 Stereo Pair, Line Level RCA
Output level, maximum	3.0VRMS (+9.5dBV)
Output Max Gain (using Analog Inputs)	8.45dB
S/N ratio	>105dB (3VRMS ref)
THD (Analog)	<0.01% (1VRMS, 1KHz)
S/PDIF Digital Input
Connector	Optical (Toslink)
Format	PCM (96KHz max), 24 bits
USB Input
Connector	USB “B” Type
Format	PCM (384KHz max), 24 bits, DSD64 (DoP), DSD128 (DoP)
Transfer mode	Asynchronous
Bluetooth
Antenna	Built in
DAC	Uses Sprout’s built in asynchronous DAC over S/PDIF (ESS Sabre 9016 DAC)
Stereo Power Amplifier Output
8Ω loudspeakers connected	50 watts per channel, both channels driven
4Ω loudspeakers connected	100 watts per channel, both channels driven
THD (Speaker Output)	<0.01% (1W, 1KHz into 4Ω)
Frequency Response	+/- 1dB (1VRMS out, 20Hz – 20Khz into 4-8Ω)
Signal to Noise	>100dB at max power into 4Ω
Headphone Output
32Ω headphones connected	500mW
300Ω headphones connected	125mW

(taken and modified from PS Audio Sprout100 Website)

Set-up

For this review, the only change in the system setup is the fact that the Sprout100 is used to act as an all-in-one on my desk, connected to my upstream components the Lenovo P43s laptop and the Yamaha CDC-905 5 CD changer player. The Onix Rocket RS250 speakers are still placed to my left and right on stands, in a rather near-field listening position. For accuracy in evaluations I sit further back to place myself in a more typical listening position. The Velodyne DLS4000 subwoofer is connected via the sub-out of the Sprout100 for a 2.1 speaker configuration. For testing purposes, I also slotted this Sprout100 in various systems in the house to see how it handled itself, which I will discuss further below.

I allow the Sprout100 for about a week (4-5 hours per day) of casual playing before I critically listen to the product just in-case there is a “burn-in” period for the Sprout amplifier.

*Note: In the picture, the Velodyne DLS-4000 is out of commission and hence why a different sub (a borrowed Paradigm X12) is there temporarily. This sub is pictured as a placeholder to where the Velodyne sat.

Build Quality and Impressions

The only one of its kind in the PS Audio lineup, the Sprout100 is a very compact-sized component at 6.2in in width. It is very well designed as well as built, with an all-metal chassis and a real walnut wood top. The bottom part somewhat contrasts to the visible upper part as it appears and feels like a rather thin sheet metal with feet already attached from factory. Everything is very minimalistic about this Sprout100, but it also appears to be rather elegant with the nice sparkly finish to the metal that spans the whole side of the enclosure. It has also got a nice heft to it, weighing in at 2.9 pounds or 1.3 kilograms. This amp also runs a little warm. Never too hot that it’s uncomfortable to touch, but it’s noticeably hot, like a hand warmer.

Overall, this Sprout100 is meant mainly for desktop use. The remote looks like a simple slab of metal with a plastic cut-out on the top having only 4 buttons: power, mute and volume up, and volume down. Not very ergonomic but it does feel good in the hand. Having those 4 buttons on the remote however, means you will actually need to switch your inputs via the knob on the front of the device. That is a pain if you are using this in a living room, sitting maybe 8 feet away, and you are switching multiple inputs. But it is not more troublesome than a vinyl player in the same room, where you will need to get up to reverse or change the vinyl. In a desk system like mine however, this Sprout100 is much less of a trouble since I can easily reach and change inputs. On the front of the device you can find a 1/4 inch headphone jack, an input knob, and a volume/power/mode knob that you can press. Each input has a tactile click to let you know you changed the input, and the knob doesn’t go 360^o because the input selections are all within the left half of the knob, as marked. The volume button is a full revolving button with tactile steps. The actual volume control is digital. You can press this button to access the power and long-press to access or deactivate the bass-boost feature on the Sprout100. Each time you switch inputs, as well as disconnect and connect your headphones, the volume lowers automatically, so you won’t accidentally blast your ears with the volume difference among the sources. I found the volume steps a little miniscule at times, such as when the Sprout100 powers my Massdrop X Sennheiser HD6XX, but in other cases just fine. Using it as a pre-amp to my Emerald Physics 100.2SE, I found the volume-level change interestingly a little too much between the steps.

Going with the minimalist design language, the selection of connections on the rear is essentially packed with the bare minimum. From the shown-picture perspective, you have the power connector on the right, which is a nice detachable one so if you so desire any power cable upgrades you are free to do so. From that to the left we have a plastic divider thing that I suspect is a wireless receiver or transmitter for Bluetooth, then your USB type B connection, optical (TOSLINK) digital inputs, then your analog inputs and outputs, your phono/vinyl input as well a sub out, and a ground for your vinyl. The speaker wire posts are those two pairs red and black jacks most left of the device, which can only accept banana connectors. Call it saving space if you will, but at least PS Audio included some cold-crimp banana connectors so you don’t need to go out and buy some just to play music through your speakers the day you get the Sprout100. I have a very similar kind that I use for my other system and I would recommend inserting the bare wire through the back not the side of the connector and cold-crimp it for a better contact. Although it might be lacking compared to full-size components, the Sprout100’s input-output connections on the rear should be more than enough for a desktop setup, where you don’t usually have many things to plug into.

Like many of the current modern integrated amplifiers, the sprout100 includes Bluetooth wireless connectivity. There is no AptX or AptX-HD feature with this Bluetooth , but I don’t think that should be an important factor, as the sound is still very good. Read on in the next section to know more on how the Bluetooth sounds despite not having AptX technology, or the latest Bluetooth technology either.

One thing I like about the Sprout100 is the fact that the headphone jack is actually a 1/4 inch variety. This is a more common connection for higher end headphones, and hence more user-friendly. The opening-side of the jack seems to be made of plastic, and I would be a little worried about longevity of the headphone jack, although it has held up with almost no visible wear at all on the plastic during the duration of the review, where I’ve done a lot of plugging in, and unplugging of my headphones. It can power most of the headphone on the market with a healthy 0.5 watt headphone amplification. The speaker amplifier power is also quite powerful capable of producing 100 watts at 4 ohms or 50 watts at 8 ohms.With at least 50 watts on tap to 8 ohms, the Sprout100 has enough juice to drive most speakers, even tower speakers like the Revel Ultima Studio comfortably. I only powered the Revel to see if the Sprout100 could handle such speakers comfortably and as it turned out, it could. The Sprout100 looks miniscule next to the Revels, which makes me marvel more at the power to size ratio of the product.

The phono input is labeled as “vinyl,” which seems a bit odd but nonetheless acceptable. I found no issues when connected this to my Rega RP1 turntable, but more on the sound in the next section regarding the phono section of the amp.

Finally, on the most spec sheet filling and standout aspect of the Sprout100, the DAC. With an ESS Sabre 9016 chip, the Sprout100 can handle not only up to PCM 384KHz, but also DSD up to DSD128. It is impressive that those options are being offered at this price point for an integrated amplifier. Other offerings at this price or higher for integrated don’t often offer the ability to playback PCM 384KHz or even DSD in my observation, so this is a good spec that will future-proof one’s listening passion if you ever do want to try such hi-res lossless formats. The hi-res DAC capability is only accessible via USB connection, however, as the other digital connection on the Sprout100 is of the TOSLINK type, which is a port limited to only 24 bit/96kHz max. For something that fits a desktop set-up very well, you’d probably be doing playback from your laptop or computer via USB anyway.

On the topic of the bass boost option that PS Audio offer with the Sprout100, I personally find this feature redundant. When setting up my subwoofer in a 2.1 speaker configuration, I typically have it a little more prominent. It does help if you have at least medium sized bookshelf speakers. What the speaker cannot reproduce, it still will not with the Sprout100’s bass boost. I still felt a need for a subwoofer on all of my speaker on songs with deep bass. It is the best implementation of bass boost I have heard though, with a nice accentuation to the low end in attempt to fill the room with something a system is lacking. I like that it is not an obnoxious bass boost that intrudes, and creates muddy sounds and vocals.

My current reference system would comprise of me having a few relatively large components on the table or on my sub (I know this is not ideal, but I have no other means). The Music Hall DAC15.2, along with the Emerald Physics 100.2SE amplifier on my table, and the NAD T747 on the sub handling preamp functions. A little unorthodox, but I was working with what I had. In comparison, the PS Audio Sprout100 is quite literally a breath of fresh air to my setup. With the PS Audio Sprout100, All I have is a compact, small box on the side of my desk, handling everything from powering my speakers to my sub easily with the sub-out, and only one power cable to worry about. The use of the Sprout100 left an abundance of space on my table that I could allocate for other functions. The simplicity of this device seems a pleasing when compared to other integrated amplifiers. It fits my desk setup almost perfectly, and, as you will see in the next section, this also packs a very good sonical experience as well.

Sound Impressions

What a simply superb desktop solution from PS Audio. Both speaker amplifier and headphone amplifier produce such a luscious sound that seems to surpass the asking price. Doing a simple blind test would give me the impression of a full-size chassis component with a low 4-digit price tag. This sprout100 is your entry into the other PS Audio’s other products, or other products with similar price tags, like a sprout growing from a dormant seed. With the way this Sprout100 performs, this product may very well sprout your inner audiophile with the joy and detail you get from listening to almost anything you throw at it.

I must admit, after the PS Audio Perfectwave MKII I had reviewed, I have experienced a few more PS Audio products, and the apparent sound signature of PS Audio is there in this very compact package. The rather spacious, deep, extended and clean sound impression is present when played through the speakers. The airiness of vocals, the smooth, slightly warm overall character, along with the impact and emotion of songs played through the Sprout100 through the digital connections is just impressive. It doesn’t exactly reach the levels the more expensive siblings achieve, but it’s impressive it does still pack what seems to be most of it in a small, relatively inexpensive package. When I hooked them up to a certain Revel Ultima Studio speakers, although I didn’t exactly evaluate them closely, they still impressed me. All for a “cheap” price of $699 to PS Audio. I could listen to the Sprout100 all day.

On the topic of listening to them everyday, although the Sprout100 does present a rather clinical, accurate and clean impression, yet it is not “cold” in terms of the characteristics. In my experience a clinical and cold sounding amp, with speakers such as the NHT Superzero, which has a rather harsh tweeter would tire me out in the long-term, but with the Sprout100, everything is just extra smooth. Both the speaker amplifier and the headphone amplifier exhibit this, and it’s just pleasing to listen to both. This makes it perfect for someone like me who likes to listen to both speakers and headphones depending on the situation. I’ve always felt the headphone aspect of my setup can be a little lacking compared to my speaker set up, but with the Sprout100 the gap has been tremendously narrowed. That said, even with the smoothness of the Sprout, it also doesn’t lose detail in exchange for the smoothness, and this is easily my favorite part of the Sprout100. I’ve had situations where I just started admiring this sonic smoothness while deep in my homework.

Large-space testing set-up, usually with subwoofer, played with a laptop/turntable but pictured without here

In my large space testing, I found the PS Audio paired with the Sony SS-K10ED, the best I’ve heard so far by one particular experience. How good it sounds throughout a room. Walking away from the set-up, I found the detail, the clarity and accuracy throughout this living room simply better than anything I’ve tested so far. It is almost as if listening off-center is almost the same as listening to it in the ideal center position. It’s an interesting observation that may not apply to everyone, but I thought that was a highlight in my experience in the open-space setup. Going on to the headphone experience, using my Massdrop X Sennheiser HD6XX, with the Sprout100 is also super smooth. It’s one of the smoothest experiences I’ve ever had on headphones. Nothing comes close in my experience so far. I also must mention, that the performance of headphone amp is on par with items that could cost as much as the Sprout100 in my experience. It is also important to note I’ve never had dedicated headphone components, but I’ve tested included headphone sections in other, more expensive integrated amplifiers, and this one surpasses most.

The phono section on the Sprout100 is also impressive. With my Rega RP1, I found the clarity to an impressive aspect. Overall, it handles older, more scratched vinyl well. It seems to mask a lot of the scratches compared to my experience when using the Rega with surround sound processors. With the only new record I have in possession, it is nearly indistinguishable from the digital counterpart. I’m happy to say this includes a pretty good phono section that I would listen to. The sound characteristics and even the superb open-space experience is also a part of the phono section experience. In my CD testing experience as well, using the optical versus the analog output from the Yamaha CDC-905 5CD changer, I found using the internal DAC of the Sprout100 to be the better of the two, providing an overall improvement in the accuracy, soundstage and the imaging. Bluetooth is also impressive, providing a very similar quality in sound compared to using the digital inputs. I did notice a slightly constrained soundstage, slightly less sharp imaging, but the accuracy was on par with using the other inputs. It is still a much better experience than any most Bluetooth devices I’ve used. Despite not having the latest Bluetooth version or AptX/AptX-HD, I think the Sprout100 should not be put off because of it, and I would give a high recommendation to at least audition it, if you’re looking for a solid performer in the wireless category as well.

One of the more unique features on the Sprout100 is the bass boost, which I think is very tastefully done, boosting the low end to where you can hear a difference, but not in an obnoxious way. That means what the speaker can’t reproduce, it still won’t reproduce. Hence, the bass boost would be best utilized if you’re connecting your sub via pre-out (the Sprout100 disables bass boost if you connect via sub-out) or have speakers that can utilize most of the sound spectrum (towers, and medium to large bookshelf speakers). With this, you can get away with not having a sub for a lot of songs. If you’re looking to play songs with deeper bass as typical in Rap, Hip Hop, some Pop and the like, this will not be enough. With other lighter bass application in music however, I never felt the need for a sub with bass boost on. I also must mention that this only applies to my medium the medium to larger speakers that I have. Particularly, my NHT SB1 (the smallest bookshelves among my references), I did feel the need to have a sub even with bass-lacking songs because of the direct comparison, and how it lacked it. With the Sony SS-K10ED, the Onix Rocket RS250, you can worry less about the lack of bass with those bigger woofers and volume. Overall, if you’re looking for more oomph all of a sudden, this is a feature I would activate immediately.

Other than how smooth the Sprout100 is, I am also very impressed with the soundstage. I can often hear an extension of the soundstagebeyond the speaker-wide soundstage, and the depth of the soundstage is deep and overall is very spacious sounding. Imaging is clear all around, and can confidently tackle the more obscure areas between the center of the speakers and the speakers themselves. The Sprout100 conveys a rather convincing stage. Not only that, the soundstaging, accuracy and clean sounding character gives it a composure and dynamic that I would normally see in components much more expensive than this. A very impressive feat.

Nit-picking on the Sprout100, the one thing that I don’t particularly like is the volume control. Versus some other PS Audio siblings I’ve had a chance to hear, the volume module can be a little flawed. Typically when listening at low volume, in better and more expensive systems, a rather emotional and dynamic experience would still be presented. With the Sprout100, this is a bit lacking. Listening to lower volumes doesn’t present that particular experience you would get a higher volumes. It’s not a big deal in my opinion, because for the price, what the Sprout100 includes already is a very impressive and very valuable package.

Conclusions

Overall, the Sprout100 is a value-packed integrated amplifier offering from PS Audio. As a younger audiophile, this offering is a very appealing one, with its compact size, tasteful bass boost, great sounding speaker and headphone amp. I’m elated to report that the Sprout100 delivers, not only in the spec sheet, but also in what goes beyond. It’s perfect on the desktop versus a living room situation, but I would also consider this a great simple large-space integrated as well. The Sprout100 is the best value for performance offering I’ve had in my system yet.