Bryston BCD-3 CD player Measurements

Sidebar 3: Measurements

As with the Hegel Music Systems Mohican, which we reviewed in the May issue, the Bryston BCD-3 has no digital inputs of any kind. This limited my measurement of its technical behavior to using 16-bit test files burned to a CD-R. (I sometimes had to eject and reload a CD-R several times before the BCD-3 would play it.) I tested the Bryston with my Audio Precision SYS2722 system (see the January 2008 "As We See It").

The Bryston's error correction was excellent—no glitches were apparent in the player's output until the single gaps in the data spiral on the Pierre Verany Digital Test CD reached 2mm in length, or the closely spaced double gaps reached 1.5mm. (The Compact Disc standard, the so-called "Red Book," requires only that a player cope with gaps of up to 0.2mm.) The maximum output level from the unbalanced outputs was 2.02V; as expected, it was twice that value from the balanced outputs, at 4.05V. Both outputs preserved absolute polarity (ie, were non-inverting). The balanced output impedance was a low 143 ohms at 20kHz and 1kHz, rising inconsequentially to 160 ohms at 20Hz; the unbalanced impedance was 72 ohms at 20kHz and 1kHz, 77 ohms at 20Hz.

Fig.1 shows the BCD-3's impulse response; it's typical of a minimum-phase reconstruction filter, with all the ringing occurring after the single sample at 0dBFS. Tested with white noise sampled at 44.1kHz, the BCD-3's output rolled off quickly above 20kHz (fig.2, red and magenta traces), but hadn't reached full attenuation by the Nyquist frequency, 22.05kHz (fig.2, vertical green line). Nevertheless, the aliased image at 25kHz of a full-scale 19.1kHz tone (blue, cyan) is suppressed by 100dB. Note also how low the distortion harmonics of that tone are. The blue and red traces in fig.3 show the Bryston's audioband response taken with spot tones; it is flat, and reveals excellent channel matching. The cyan and magenta traces in this graph show the response with preemphasized data. The slight lack of energy in the mid-treble seems to be typical of modern CD players—the Hegel Mohican behaved identically (footnote 1), perhaps due to the fact that it uses the same AKM AK4490 DAC chip as the BCD-3.


Fig.1 Bryston BCD-3, impulse response (one sample at 0dBFS, 4ms time window).


Fig.2 Bryston BCD-3, wideband spectrum of white noise at –4dBFS (left channel red, right magenta) and 19.1kHz tone at 0dBFS (left blue, right cyan), with CD data (20dB/vertical div.).


Fig.3 Bryston BCD-3, frequency response at –12dBFS into 100k ohms, without deemphasis (left channel blue, right red) and with deemphasis (left cyan, right magenta) (0.5dB/vertical div.).

Channel separation (not shown) was superb, at >120dB above 200Hz, while the analog noise floor (fig.4) was both very low in level and free from any power-supply–related artifacts. Fig.5, the spectrum of the player's output while it played data representing a 1kHz tone at –90dBFS actually shows the low-frequency spectrum of the dither noise used to encode the 16-bit test signal. With undithered data representing a 1kHz tone at exactly –90.31dBFS, the Bryston's low self-noise allows the minimum-phase ringing on the waveform transitions to be clearly seen (fig.6). The three DC voltage levels described by the data are well defined.


Fig.4 Bryston BCD-3, spectrum with noise and spuriae of dithered 16-bit, 1kHz tone at 0dBFS (left channel blue, right red) (20dB/vertical div.).


Fig.5 Bryston BCD-3, spectrum with noise and spuriae of dithered 16-bit, 1kHz tone at –90dBFS (left channel blue, right red) (20dB/vertical div.).


Fig.6 Bryston BCD-3, waveform of undithered 16-bit, 1kHz sinewave at –90.31dBFS (left channel blue, right red).

Confirming the low distortion seen in fig.2, the spectrum of a full-scale 1kHz tone is very clean (fig.7), with just the third harmonic at 2kHz visible—and even then, it lies at –100dB (0.001%). I then tested for intermodulation distortion with an equal mix of 19 and 20kHz tones; the resultant spectrum looks hashy in the audioband (fig.8), but this is an artifact of the 16-bit encoding. Actual intermodulation products are very low in level even into 600 ohms, as are the aliased images at 24.1 and 25.1kHz.


Fig.7 Bryston BCD-3, spectrum of 1kHz sinewave, DC–1kHz, at 0dBFS into 100k ohms (left channel blue, right red; linear frequency scale).


Fig.8 Bryston BCD-3, HF intermodulation spectrum, DC–30kHz, 19+20kHz at 0dBFS into 600 ohms (left channel blue, right red; linear frequency scale).

Finally, though there is a slight widening at the base of the spectral spike in fig.9 that represents the high-level tone at exactly one-quarter the sample rate, all the odd-order harmonics of the LSB-level, low-frequency squarewave lie at the correct levels, shown as the sloping green line. The BCD-3 offers excellent rejection of word-clock jitter.


Fig.9 Bryston BCD-3, high-resolution jitter spectrum of analog output signal, 11.025kHz at –6dBFS, sampled at 44.1kHz with LSB toggled at 229Hz: CD data (left channel blue, right red). Center frequency of trace, 11.025kHz; frequency range, ±3.5kHz.

This Bryston CD player's measured performance reveals superb audio engineering.— John Atkinson

Footnote 1: See fig.3 here.
Bryston Limited
PO Box 2170, 677 Neal Drive, Peterborough
Ontario K9J 6X7

mrkaic's picture

Just look at the measurements!

Axiom05's picture

It doesn't play SACD's or DVD-A discs. Is a CD-only player really competitive in 2017? For less than half the price I can buy a top of the line Oppo (UDP-205) that plays every 5" disc in existence, plus uses the ESS 9038PRO DAC (and I bet it comes with a remote control at no extra cost). Something just seems wrong with this picture...

johnnythunder's picture

while not inexpensive, based on AD's review and JA's measurements, this seems to be a very well made and great sounding CD only player. I'm sure the Oppo is a good machine. I've only read great things about its blu ray capabilities. Enjoy it. But it's not a proper comparison.

watchdog005's picture

The point is if it can play CD audio better then a modern day SACD or DVD machine can play CD audio then it's worth owning even if it cannot play SACD or DVD audio. They made these and tuned them specifically for CD audio.

hnickm's picture

Ah, I remember - those are the hard media things you used to rip so you could store AND FIND the songs and play on a music player, like the excellent Bryston BDP P1 (less than $1,500). Or if you want to go all out, the BDP 2 (less than $2,500). Either of these solutions seem superior to the silver LP solution.

johnnythunder's picture

of the future or even the present for that matter, it's a review of a cd player - which, considering how many companies are still investing in new state of the art players and considering how many people still have massive cd collections - is still a viable and often great sounding format for reproducing music.

jmsent's picture

... and the specs of the individual components, you'll see that the transport and all the digital processing circuitry are all fully capable of reading and decoding far more formats than Redbook CD. It comes as no surprise that the CD measurements are going to be great, as modern transports and DACS designed to decode 24bit/192kHz files and greater are not even breaking a sweat when it comes to CD playback. It's not as though they've employed some "super special CD only components" to make a machine that will outperform every multi format player. It's more like they built a high quality multi-format player and programmed out the "multi". At least, that's how I see it . YMMV.

johnnythunder's picture

Hegel is doing the same thing w their Mohican CD player. Over-engineered and optimized for purely redbook cd playback. Not another piece of electronics wasted for anything other than that. I get your point but it's a little like criticizing a $35000/ 100 lb. PASS amplifier for only being a mono block and not being for that price and size a maasive home theatre amplifier.

smileday's picture

Looking at the owner manual of Bryston BCD-3 CD player, I found that the program function is missing. Why?

$499 Marantz CD6006 and $1499 Onkyo C-7000R have the feature.

It is just a little bit of coding, but Bryston skipped it for their $3495 CD player?

Or omitting the programming feature leads to better sound quality?

johnnythunder's picture

Once again, criticizing a feature that has no direct impact on SOUND QUALITY is missing the point of this review and the product and others like it.
Another analogy - it's like someone criticizing a $10,000 turntable/cartridge/arm combo for only playing one record at a time. Yes, back in the 60s you could buy $69.00 turntable that could stack record after record!

smileday's picture

Single record playing turn tables are designed that way to achieve better sound quality.

By skipping the programming feature on a CD player, do they achieve better sound quality?

Allen Fant's picture

Nicely done- AD!

have any of guys compared this new BCD-3 to the older BCD-1 spinner?

Ortofan's picture

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its intrinsic resolution is better than is needed by the CD medium, then what does the Bryston unit do for about 10 times the price?