Cary Audio has always been known for exceptional engineering and build quality. The new SI-300.2d integrated amplifier is their attempt to provide state-of-the-art sound in a combined DAC + preamplifier + power-amplifier package.

Top-grade parts and detailed engineering are used to provide an amplifier intended to compete with the best of separate components.



Cary Audio SI-300.2d Integrated Amplifier

  • Class A preamplifier section
  • Class AB output section intended to have tube sound
  • Up-sampling and re-clocking DAC features
  • Stable into almost any load

The Cary Audio Company is based in Raleigh, North Carolina. They have been in business since 1989. They’re best known for their vacuum tube stereo products that are known to be reliable, exceptionally well-built and great sounding. After moving into the digital arena with a brace of home theater products, Cary is now returning to their two-channel roots and offering a solid-state integrated amplifier intended to offer tube sound.

Digital Outputs:

Coaxial, TOSLINK operating at Sample Frequency (Fs) from 44.1kHz to 192kHz, 16-24 bit

Digital Input Sample Rates:

USB operating at Sample Frequency (Fs) from 44.1kHz to 384kHz, 16 to 32-bit, DSD 64, DSD 128 and DSD 256
Bluetooth operating at Sample Frequency (Fs) 44.1kHz, 16-bit AES/EBU, Coaxial, TOSLINK operating at Sample Frequency (Fs) from 44.1kHz to 192kHz, 16 to 24-bit

Master Clock Jitter:

Below measurable levels

Digital Sampling Rates (Fs):

44.1kHz to 768kHz

Digital Filter:

8x Oversampling Digital Filter

Digital/Analog Converters:

2-channel AK4490EQ


CSR Bluetooth v4.0 with aptX® low latency audio decoder

Subwoofer Filter:

3rd-order Bessel

Preamplifier Outputs:

Balanced XLR , Single-ended RCA

Analog Input:

Single-ended RCA x 2
Balanced XLR x 2

Analog Input Impedance:

10kΩ Unbalanced
20kΩ Balanced

Power Amplifier Outputs:

2 x 300W RMS in 8Ω from 20Hz to 20KHz
2 x 450W RMS in 4Ω from 20Hz to 20KHz

Circuit Type:

Solid-state, Class A/B

Frequency Response:

10Hz – 50kHz +/- 0.1dB (at 10db below rated output power)

Distortion (SMPTE-1M):

< 0.5%

S/N Ratio:

>100dB, “A” Weighted


Full short circuit, thermal, Ultrasonic, RF
signal muting, current limiter


Trigger output 12.0V DC x 1
IR control x 1


Ethernet RJ-45 full remote configuration interface
Wi-Fi 802.11b/g/n

Power Input:

Configured at factory for either 110-120 or 220-240V AC, 50-60Hz

Power Consumption:

950 Watts (4 ohm load at full output)


Black powder coated matte chassis with silver or black aluminum faceplate




6.0″ H x 17.25″ W x 18.0″ D


$5,995 USD




Cary Audio, integrated amplifier, DAC, premium quality, stable amplifier section, able to drive difficult loads

Associated Reviews

Cary Audio CD-500 CD Player
Cary Audio @ the Las Vegas Audio Show


Integrated amplifiers combine a preamplifier section and a power amplifier section in a single chassis. Some integrated amplifiers can include multiple channels for audio-video use, but the majority (including the SI-300.2d) are stereo, or two-channel devices. Integrated amplifiers can also include other functions. In the past, an AM/FM tuner was also included in the same chassis making it into a stereo receiver.

Because the majority of consumers no longer listen to radio in their homes, and because most now listen to digital sources either streamed from the Internet, wirelessly streamed or from a server computer, it has become common to eliminate the tuner section and substitute a digital-to-analog converter, known as a DAC.

Cary Audio has included a DAC from their premium products in this integrated amp. The chip itself, an AK4490EQ from the Asahi-Kasei Microdevices Company, has a good reputation. It sports proprietary TruBit™ up-sampling and OSO™ re-clocking features. The intent of up-sampling is to increase the frequency of the audio signal so that more gradual filtering can be employed. The DAC also increases the bit depth of an incoming signal to 32-bits for greater resolution. The purpose of re-clocking the digital signal is to prevent jitter from affecting the audio output.

Digital inputs include Cary’s XMOS USB input, capable of true native DSD signals up to 256kHz and PCM/DXD up to 32-bit/384kHz. The integrated amp also offers two coaxial inputs, one optical input, an AES/EBU input and Cary’s aptX® Bluetooth input. All S/PDIF and Bluetooth digital sources allow for 10 TruBit™ selectable up-sampling rates and PCM-to-DSD conversion options.

The preamplifier runs in Class A mode to minimize crossover notch distortion.

The Class AB power amplifier section provides 300 watts-per-channel into eight ohms, 20Hz-20kHz. Into four-ohm loads, the power amp provides 450 watts-per-channel at the same bandwidth. This is not indicative of any power supply limitation, but rather a limit imposed by the heat dissipation fins. The best power amplifiers can double their eight-ohm power output at half the impedance, and were it not for the heat sinking limit, this Cary could also. At these outputs levels, distortion (SMPTE-IM) is specified at less-than 0.5%. This is a completely academic specification since nobody will ever be listening at full power.

One specification that is spectacular is how quietly the Cary runs, sporting a greater than 100 dB signal to noise ratio. This spec ensures that there will be no background noise heard from the amplifier at any reasonable volume level. And listening bore this out. With no signal through the amplifier, and with the volume control set to 100%, no audible noise could be heard at the speakers.

It also bears mentioning that the SI-300.2d successfully drove Martin Logan hybrid electrostatic speakers. These speakers have a 20kHz impedance of only 0.6 ohms. Despite this, it never became exceptionally hot, shut itself down or hiccupped. Another power amplifier blew its output devices when hooked up to the speakers, but the Cary remained unflappable.

The front-panel display also merits some conversation. The panel on the left-hand side of the central volume control knob displays information about the input selection, DAC frequency and volume. Changing sources temporarily blanks the left panel and displays a much larger name of the newly-selected input. The large text persists for a second or two. This is very handy because at its normal size, the left-hand panel text can be hard to read. The panel on the right-hand side of the central knob displays a pair of illuminated virtual power-output meters.

And this brings up one of my (very few) complaints about this integrated amplifier. Most of the time, the meters can’t be readily seen from across the room, so they’re not particularly useful. Furthermore, the meters are significantly brighter than the function display to their left, and can sometimes glare badly enough to make the already hard-to-read function information even harder to understand. I wish that Cary had made the power meters a defeatable feature. I’d much rather have larger, more legible source, DAC and input information than the meters.


But the meters are a “gee-whiz” feature, and I can understand how many users might like them.


Well, this section is easy – I took the amplifier out of its box, placed it on the equipment stand and connected the speaker wires, and an input coaxial cable, and voilá – Music!

A few days later, after the amp had played long enough to be burned-in, I took the time to read the owner’s manual. No surprises. Everything works as expected.

Eventually, I hooked up some analog sources via XLR to try different, outboard DACs. I also tried out the TOSLINK optical connection. The SI-300.2d sounded just as good either way.

I also took the time to pair my phone with the Cary via Bluetooth to stream some CD-quality audio. The sound was indistinguishable from the other inputs. So even though I was initially highly skeptical of sound quality over Bluetooth, the amp surprised me again.


The back panel is well laid out and easy to hook up. I particularly appreciated the availability of not one but two XLR inputs. I tried the Cary’s DAC with both coaxial and TOSLINK optical inputs – no audible difference. Those wishing to drive more than one pair of speakers might wish for a second set of speaker terminals, but I didn’t find that to be a concern.

Note also that the SI-300.2d offers digital outputs in both coaxial and TOSLINK optical flavors. This makes it easy to daisy-chain components if you need to do that. A cinema bypass option allows it to be used as a power amplifier for home theater systems.

Having a set of preamp output jacks is also helpful if one wants to run subwoofers in parallel with the main speakers. Since there is no bass-control filter, the pre-out jacks are full-range, and any subwoofer blending will need to be done using the plate amplifier on the sub.


Looking inside, I was particularly impressed with the toroidal transformer, the clean layout and the heavy-gauge speaker wiring. Many components skimp on power supply and speaker wiring (ever looked inside an AV receiver?). The Cary seems exceptionally well-designed and built. This level of build quality goes a long way toward explaining its premium price.


The remote is also quite a nice piece of work. In addition to power, volume and input selection buttons, it offers several features that I found exceptionally useful.

One button (labeled SRC) can be used to cycle through the DAC options on the fly! Options include:


I found that for my 44.1kHz CD collection, the 705.6 (16x oversampling) mode sounded marginally better than the rest.

Another button that I found useful was Display. It allows one to cycle through three LED display brightness settings and an Off position (useful when the amplifier isn’t being used). The Balance and Mute buttons are also nice touches.

In Use

As mentioned earlier, one of the first speakers that I used with the Cary was a pair of Martin Logan Impression ESL 11A loudspeakers (review here – [insert link to ML review on Secrets website]). These speakers are difficult to drive for some amplifiers because of their decreasing impedance in the treble. In fact, it drops all the way to 0.6 ohms at 20,000Hz. Since most amplifiers aren’t rated for less than four ohms, this is WAY out of the design envelope for most amplifiers. Some amps absolutely cannot drive this load, but the SI-300.2d did so without complaint. Even at the end of some long and loud listening sessions, the heat sinks, though warm to the touch, were not really hot. This argues for conservative design and exceptional stability in its power amplifier section. Bravo!

Now that said, even though the Cary could drive the very particular Martin Logan speakers, and even though it sounded better with them than either of the tube amps I had in the house, you could still hear that it wasn’t necessarily a happy date – for either the speakers or the amp. Yes, they sounded good, and yes, the Cary drove them without complaint, it just lacked the magic one would expect from $16,000 worth of equipment.

It isn’t the fault of the speakers – and it isn’t the fault of the amp. Sometimes you just get an uneasy match. It’s like being asked to tango with your girlfriend’s mom – slightly uncomfortable for everyone…

But THEN I hooked up the Cary with a pair of speakers that I thought would be equally unsuitable – and for all the opposite reasons. Those speakers were the Tekton Pendragons.


Where the Martin Logans had low impedance, the Pendragons were an easy-to-drive 8-ohms. Where the Martin Logans had self-amplified bass, the Pendragons were a completely passive speaker with two 10-inch woofers. The Pendragons are highly efficient, and since they demand so little from the amplifier, I didn’t expect too much when I hooked them up to the very-high-powered Cary. In fact, I even expected a bit of background noise, and possibly some glassy-sounding midrange (which is what I’ve heard from several other high-powered amps using these speakers). What I actually got was something more than expected.

Let me be up front, here – I’m a tube guy. That’s just how it is. I like the sound of tube audio and have owned some pretty high-end solid-state amplifiers before that just didn’t do much for me. Even the ones that I kind of liked eventually wore out their welcome and took that lonely hike to eBay. Now given that set of internal prejudices, I was prepared to give the SI-300.2d a great big yawn.

But what I heard was different! I didn’t expect the amp to sound like tubes, and despite Cary’s stated attempt to achieve that, this amp does NOT sound like a tube amplifier – except for two very important aspects…

The single most attractive aspect of tube amplification for me, is that the soundstage becomes significantly more expansive. And the Cary nailed that aspect just fine, thank you. With the Cary in the mix, the Pendragons disappeared – just as they do with my favorite pair of tube amps. Close your eyes – you can’t point to the speakers. You’re just immersed in a soundstage that not only appears in front of you, but that seems to wrap around on both sides. Marvelous!

Another attractive aspect of tubes I admire is their ability to provide realistic dynamics, even at lower volumes. Horn speakers do this well, but you pay for that dynamic ability with coloration. The strength of the Pendragons is that they can give you a large portion of those low-volume dynamics without the coloration but ONLY IF the amplifier is up to the task. The Cary is! No, it still can’t rival the best of my tube amps, but it is most of the way there (and without the tubes’ romantic colorations).

So although the Cary brought out the Martin Logans’ transparency, it lacked the bass slam of the tube amps. Now (with the hybrid Martin Logan speakers) this may not be a valid criticism because they have self-amplified bass and the Cary isn’t driving them directly. But the Martin Logan bass had LOTS more slam with the tube amps despite them being self-amplified.

The Cary brought out the imaging AND provided tight bass with the Tekton Pendragon speakers. To see if I could determine why, I added a third pair of speakers to the mix: Axiom Audio M-100s.

And once again – the Cary showed its mettle by providing both the generous soundstage and low-volume dynamics that I’ve not previously heard from a solid-state amplifier. I’d like to hear the Cary with some imaging-champ speakers like KEF Blades or Thiel 3.7s!

Associated equipment used for this review:
  • MacBook Pro running JRiver Media Center 22
  • Red Book CD collection ripped in WAV format
  • Oppo BDP-105 used as a DLNA (Ethernet) DAC
  • SACD discs played via the Oppo
  • iPhone 6+ with Bluetooth enabled
  • Cary SI-300.2d integrated amp with built-in DAC
  • Martin Logan Impression ESL 11A speakers
  • Tekton Pendragon speakers
  • Axiom Audio M-100 speakers
  • Interconnects from Audioquest, Emotiva, BlueJeans Cable, and others
  • Factory CaryAudio power cord
  • Speaker cables from BlueJeans, Nordost Flatline, Straightwire Symphony SC, and others

The sound of the SI-300.2d, if I had to sum it up in a word, would be “subtle.” It can run with most anything in some parts of the frequency spectrum, and is always a good imaging amp, but it’s very hard to separate the impressions of the DAC from those of the amplifier itself.

If I had to judge, I’d say that the preamp/power-amp section is very neutral. The DAC has some voicing available via its many oversampling and DSD options, and some experimentation is probably needed to select the option that best matches your speakers.



Gordon Lightfoot’s classic The Wreck of the Edmund Fitzgerald is well-recorded and has a multitude of (sometimes subtle) special effects going on in the background. Above it all, Gordon’s guitar should have audible overtones. I found the treble on this cut clean and impressive.

Henry Mancini’s The Pink Panther Theme is a good example of a well-recorded orchestra with lots of treble and sparkle to be appreciated.

Itzhak Perlman’s rendition of Paganini’s Caprice No. 1 in E, Opus 1 is my standard for overtone reproduction. The violin should be startlingly present, and the overtones should be audible above the resonance of the violin body.

It’s A Beautiful Day’s rendition of Bombay Calling is another view of violin overtones, in a completely different context. Amplifiers or speakers that lack treble extension will shut this cut right on down. But the Cary makes the song sound open and extended.



The Glenn Miller Orchestra’s String of Pearls is not only a familiar classic, but the horn section is a marvel. Listen for separation of brass instruments – they should sound like a group of individual horns – not just a massed blob.

Herb Alpert’s The Lonely Bull is another familiar classic, and again the horn section is the thing to listen to. The music should swell and dip, sounding as if you’re at a live performance.

Jackson Browne’s Our Lady of the Well is a far more delicate song. His voice should be in the room with you, and should not sound different in timbre despite its swings in volume.

And what midrange tour could be complete without the king of them all – James Brown’s I Feel Good (I Got You) is a song I’ve appreciated since I was a child (I used the soul screams to irritate my mom). This may not be the very best recording in the world, but it’s definitely one of his best performances. Listen for the details in both the band and in the voice. Don’t hear any detail? Maybe you need a Cary Audio amp…



George Thorogood and the Destroyers’ live performance of One Bourbon, One Scotch, and One Beer is a song that you’ll either love or hate – but the bass slam in the song is not to be denied. I like this song as a test for amp and speaker combinations – many combos that can do chamber music well just lose it completely when asked to play live rock. Rock doesn’t get much more live or raw than George. I played this for a friend on my system, and when he went home he played the same song for his wife. After seconds, they both decided they didn’t want to listen – their system just couldn’t do it justice. The SI-300.2d with the Pendragons rips this one right on up!

Herbie Hancock’s Dis Is Da Drum has tremendous low-bass slam. The recording shows its age, but the bass is impeccable. If your amp can’t do low bass slam, you’ll never hear this as it was intended. The Cary brings the bass.

James “12-inch” Andrews and the Crescent City All-Stars’ rendition of When the Saints Go Marching In (titled Funky Saints) is another song that just doesn’t sound right with insufficient bass. The Cary does it proud.

The previous three selections focus on bass quality. But the truest test of bass quantity is found in Lady GaGa’s Dance In The Dark. When the bass synth/drum comes in toward the beginning of the song, you’ll find out things you never knew about your amplifier, your speakers and your room. If you have peaks in your response, the bass will become pure mush. If your speakers can’t reproduce low bass at volume, you’ll get the same mush. If your amp can’t control the woofers? More mush. But when things are right – oh my! The Cary gets this right too!



Luther Kent’s Cold Gritz and Blackeyed Peas band hit their peak in about 1970. Their radio hit at the time was Bayou Country. I recorded it off the airwaves and sent a cassette tape to my former schoolmate serving in Vietnam. He mailed me back that it was his squad’s favorite party song. The backup hotties (the Blackeyed Peas) should sound distinct from Luther’s front & center wail. The guitar should sound ethereal. The SI-300.2d brings the magic!

Hank Williams Jr. does Mind Your Own Business with a cast of characters. See how many you can recognize from their voices. The Pendragon/Cary Audio combination make this sound like a live stage show.

The 59th Street Bridge Song by Harpers Bizarre was a big radio hit in its heyday. And despite that, it is well-recorded. I can’t imagine ANY current radio hit being well-recorded, but I digress… The instruments and vocals in this cut should be startlingly distinct. The Cary gets the separation correctly.

One of my favorite recordings is the Bagels and Bongos CD by the Irving Fields Trio. The particular cut Belz contains not only wide dynamic range, but also space between the musicians. See if your setup can separate the trio members. The Cary handles it just fine.

On The Bench

Since I lack the equipment to bench-test electronics, I’ll refer you to Cary Audio’s website for any measurements (beyond the published specifications) that you might be interested in.

I did try all of the up sampling and DSD conversion options of the Cary’s DAC. I couldn’t say which was best, because all sounded close, but I generally preferred the highest available up-sampling without DSD conversion. Could I have picked out my favorite in a double-blind test? Probably not, but spending some time with each of the options (and keeping good notes) can help.



At this level, value is somewhat difficult to evaluate. There are a LOT of integrated amplifiers for far less money. And there are a LOT of separate preamp/power-amp combinations for less money. But think of what the Cary Audio SI-300.2d does that those other components can’t:

  • It has much of the soundstage and dynamic capabilities of tube componentry
  • It has proven itself to be bulletproof when driving difficult loads
  • It is the best-sounding integrated amplifier that I’ve yet heard
  • It has a DAC that could easily cost more than the entire price of this integrated amp

Taking into account all the above, I’d have to say that the Cary Audio SI-300.2d IS worth its asking price. I’ve heard nothing for any lesser price that can compare.

  • Able to drive any speakers that I tried it with
  • Wide variety of DAC options & future upgradability
  • Variable panel lighting options
Would Like To See
  • Larger text on LED panels
  • Ability to turn off the power meters
  • Optional second set of speaker terminals

The Cary is truly two products in one – a versatile and future-ready DAC and a muscular integrated amplifier. Both are exceptionally high-quality, and they sound that way. The DAC can vary its sound signature somewhat with multiple oversampling options. So unlike many high-end DACs that have only one voice, the Cary’s DAC can be tweaked (and from the listening position by remote control) until you find the best match for your system. The integrated amplifier section is FAR more robust than many preamp/power-amp combinations. The separates not only cost more, but also lack (in many cases) the low-impedance stability that the SI-300.2d exhibits.

Cary states that their design with this amp was to be a solid-state component that had the best of tube sound. And despite the fact that you’ll not mistake this amplifier for a tube component, the Cary does bring sound-staging and dynamics that are quite tube-like.

By any consideration, the SI-300.2d is a smashing success. It’s the best integrated amp that I’ve heard and certainly warrants a serious listen if you’re considering spending anywhere near its $5,995 list price.