The following Is a review of the Chord Hugo Table Top (TT) DAC/Headphone Amp/Premap:
I’m going to preface the review with an observation from Rob Watts, the TT2 Chief designer:
“If you put 12 audiophiles in a room and had them evaluate a PERFECT DAC, there would be 13 different opinions on the DAC’s performance”.
Given that as a backdrop, lets crack on with the review.
The Chord Hugo TT2 is the second from the top of the Chord DAC line. It has the following features:
- Two operating modes: DAC and AMP. The DAC mode outputs a fixed voltage from the RCA or XLR outputs. The AMP mode acts as a preamp to an external amp. The single ended mode outputs up to 7.3 watts @ 8 ohms, while the XLR mode outputs 18 volts, which is enough to drive efficient speakers, or inefficient headphones.
- There is a HI gain and LO gain mode for the amplifier. The LO gain is 9 dB less than the high gain. This is achieved by inserting a resistor in the amp stage to reduce gain. The advice from Chord is to generally use HI gain, unless using a very sensitive set of IEM headphones.
- There are 3 headphone inputs, two ¼ jacks, and one 3.5 mm jack. Whenever the headphone jack is used, the amp outputs are muted.
NOTE: There is only one analog amplifier in the TT2. It is a high quality, very linear amp with excellent distortion numbers, and plenty of power via XLR to drive inefficient headphones or desktop speakers. The headphone jack has more than enough power to drive most headphones sufficiently. Will have more to say on the amp later in the review.
So, how does the TT2 sound? Let’s find out.
The review was conducted with the following configurations:
- TT2 standalone using Headphone Jack with Abyss 1266 or Sony MDR Z7
- TT2 standalone using XLR out with Abyss 1266
- TT2 standalone using SE out to the Kludge OTL Tube amp with Abyss 1266 or Sony MDR Z7
- TT2 with M-Scaler using XLR out with Abyss 1266.
Initially tried the TT2 with the Abyss 1266 using the Headphone Jack. The sound was excellent overall, with all of the strong points Chord DACs are noted for. Having said that, the dynamics seemed a bit restricted, so quickly went to AMP mode, connected the Abyss 1266 via XLR using MIC adapters and XLR cables, and again listened. The soundstage seemed to have added depth, the headphones played louder., more slam with bass notes. Have some back-and-forth correspondence with Rob Watts regarding SE vs Balanced connection. He explained that the DAC amp is an SE design, and that there is always a small loss of transparency with balanced, due to the extra circuitry with headphones. He also convinced me to try again the SE out for the Abyss 1266, assuring that the amp had more than enough power to drive the headphones to 120dB! At that point, went back the headphone jack in AMP mode, and conducted the listening test in that configuration. Of course, Rob was correct, the transparency is better out the headphone jack with the 1266. I think I fell victim to the volume not being level matched initially.
The TT2 octave to octave balance is first rate. Bass reproduction is the best I’ve heard to date. It’s the type of bass that one feels with the lowest registers, stand up bass has outstanding transient response, plenty of impact, but NOT overpowering or artificially boosted. The mid-range is without question the cleanest and most detailed I have ever experienced from a headphone or stereo setup with this DAC. What this DAC gets right that almost no other DACs achieve at this level of performance is the depth of soundstage, the ability to clearly hear ALL of the separate instruments with realistic sounding transient responses. Low level detail is incredibly transparent. The listener will hear nuances with this DAC that they likely have not experienced before. The treble from the TT2 is outstanding, digital glare from harsh distorted treble is almost nonexistent. The transient response with the treble adds to the sense of space and realistic sounding presentations.
This had me thinking about the talk Rob Watts gave at the RMAF:
I think this talk explains better that certainly I can how the Chord DACs work, and why they sound so damn good. One thing that really became apparat over time was that this DAC has significantly less distortion over most other DAC designs. The more I listened to the TT2 via XLR, the more I came to appreciate the sound from this DAC, and the near total lack of distortion characteristics. Rob states that many DACs have distortions that listeners tend to like, which makes the sound brighter, crisper, etc. In fact, many audiophiles actually like the types of distortions generated from these DACs.
The allure of tube amps, for example, is the distortion characteristics, which can be very pleasing to the listener. Which brings me to listening to the TT2 with the OTL headphone amp. This combination is quite seductive, with a bit more emphasis in the presence region, along with a slightly depressed treble. Audiophiles seem to love elevated bass, a bit extra presence, and slightly lower treble. This is exactly what the Kludge brings to the table. I found this to work best with older recorded music, where the slightly extra body provides a bit more warmth.
The filters and crossfeed functions work in the same manner as the Hugo-2. I tended to use the default filter for modern CDs, the warm filter for older CD’s, and the HF rolloff filter for SACD’s The crossfeed function was quite useful with old stereo recordings to adjust the soundstage.
Now, add in the M-Scaler, and things get REALLY interesting. All aspects of sound reproduction improve markedly. Bass gets additional resolution, with improved transient response. The midrange gets the largest amount of improvement, with increased clarity and better instrument placement. Treble also gets better, with any trace of digital glare removed. A 44.1 CD sounds as good as Hi-Res files on other systems. The soundstage gets much deeper, wider, and adds additional height.
In summary, I find the TT2 to be among the very best options for digital playback. The Chord approach definitely works as stated, and in my opinion, offers perhaps the cleanest, distortion free sound with depth, transient response, and spatial realism available. I’ve owned R2R DAC’s in the past, and the Chord approach just plain sounds better to me. It’s a lot easier from a technical aspect to get consistency from unit to unit with the Chord approach as opposed to R2R DAC offerings. The Chord DACs have proved to me that the key to getting digital right is reconstruction and filtering of the incoming digital data stream. So, given the technical challenges of decoding the bits, and then filtering the bits based on how they are decoded, one cannot assume that the bits are being decoded and then filtered correctly. The talk by Rob Watts outlines the shortfalls and challenges with DAC design. The TT2 is not perfect, but the sound is closer to reference than the vast majority of DACs currently available. The M-Scaler gets the TT2 that much closer to an absolute reference. The TT2/M-Scaler is closer to reference than the Dave standalone. That’s good enough for me for now.
One other item: The Amp section in the TT2 is among the cleanest and least distorted presentations I’ve come across to date. The approach taken with the amp section was the same as Nelson Pass: Make it as simple as possible, but no simpler. This experience has re-enforced an old axiom from the past: The less amp stages used, the cleaner the output. This is very true in spades with the TT2. To me, adding an external headphone amp will only add distortion and diminish transient response, the single biggest attribute of this product. Still, sometimes, distortion in the guise of an external tube headphone amp may be desirable on occasion.