Confused about the DV2b

[pedalhead]

Hi all,

I'm currently the owner of a Premier 11A / PV12 combo, and have a DV2b on the way from a friend. I'm a little confused about this model though as it's not mentioned at all on the CJ vintage products site. There's a bit of chatter about it online, but I can't find any user guide, nor details about which dac chip it uses.

Can anyone shed some more light on this CD player please?

Many thanks,

Mark.

[Joe Appierto]

This is from the c-j web site:

The D/A-2b and D/A-3 Digital Processors
A digital processor accepts the data stream from the transport and converts the numerical data back into music. Several circuits are involved in this process. Of these, data conversion, analogue filtering and power supplies are particularly important to faithful music reproduction.

We have chosen to use bit-stream DAC chips for these processors because we find that they offer by far the most musical performance. The edgy, unmusical sound that we typically find with multi-bit DACs is probably attributable to a type of crossover-notch distortion which is intrinsic to these designs, and absent from bit-stream converters. This distortion is essentially invariant to signal amplitude, making it most noticeable on delicate musical passages, obscuring ambience information, tonal nuance, and harmonic subtlety The bit-stream approach reproduces these important elements of musical information far more naturally

The final stage of any DAC is the analogue output stage. This stage is a low-pass filter, designed to remove high-frequency (supersonic) artifacts of the conversion process. In the majority of units presently on the market, this critical function is performed by an IC op-amp, with much the same result as would be expected from using that device in a preamplifier. In contrast, the output stages of the D/A-2b and D/A-3 are designed and executed in much the same way as our preamplifier circuits, using discrete devices – the D/A-2b using vacuum-tubes, the D/A-3 using field-effect transistors.

Always important, power supply des critical to the musical performance of a tal processor, because of the need to isolate the sensitive analogue audio stages from the very high-frequency noise generated in the digital sections. In the D/A-2b and the D/A-3, dc voltage is supplied to the audio stage by a discrete regulated power supply, designed to offer vanishingly low impedance at all audio frequencies. These power supplies use polypropylene and polystyrene capacitors exclusively A similar, separate regulator supplies DC to the analogue circuits in the DAC chip – the origin of the audio signal.

The DR-1, D/A-2b and D/A-3 have been designed and produced with care to transform digital sources into a musically rewarding experience. These digital playback systems offer depth and focus of soundstage, tonal accuracy, and an ability to convey nuance in musical performances that many audiophiles have felt would not be possible from compact disc.

D/A-2b Vacuum-Tube Digital Processor
— introduced September, 1995

Specifications:
Sensitivity: 1.0 VRMS output at 0 dB (maximum output)
Distortion: less than .05% THD
Bandpass: 5 Hz to 20 KHz, +0, -5 dB
Hum and Noise: 92 dB relative to 1.0 V output
Phase: 0, 180 degrees of phase shift switch selectable
Inputs: One RCA coaxial, one BNC coaxial, one TOSlink optical. ST Glass optical input is optionally available.
Digital Output: one BNC coaxial
Mechanical
Dimensions: 14.375D x 19W x 3.315H inches
Weight: 19 tbs.

Hope this helps.

[pedalhead]

Thanks for the info, Joe. I'm mostly confused because the DV2b doesn't seem to be referenced as a model in itself. That excerpt from the CJ web site mentions the DR-1, D/A-2b and D/A-3, but not the DV2b...? Cheers. Mark.

[Joe Appierto]

You're quite right, sorry about that.

[pedalhead]

Hey no problem, I appreciate you making the effort to help. Perhaps I'll get in touch with CJ & see what they have to say about this unit. Cheers. Mark.

[pedalhead]

Just for completeness, here's the response I received from CJ...

DV2b was very popular, it's not on the website, because well frankly we lost all the promo materials for it.
it had a TDA1305 DAC.
I can not recommend anything about it at this point because it is unrepairable by us.
Many parts are no longer available and haven't been for many years in most cases.

[admin]

it's not on the website, because well frankly we lost all the promo materials for it.

That's actually kind of funny.

[pedalhead]

Yes I thought so too

[Big Dog RJ]

Hi mate, came across your post Re. To the DV2b.
Sorry, I should have replied to this much earlier.

I used one back in home town cmb for quite a while until certain parts stared to fail due to excessive humid /tropical climes. Anyway, CJ replaced it with a new unit and shipped across the necessary parts required, so that in the future we would be covered for a few years.

The transport unit is a Phillips, the exact laser reader model number I'm not sure of but it was the best Phillips used at the time. Later on down the line, another owner had the same unit fail on him as well, and CJ in Singapore, sent across a Sony transport mechanism, saying that this was a suitable replacement for the Phillips. Phillips no longer made the original transport unit for the dv2b, hence CJ no longer offered repairs...

The DAC chips are Toshiba, highend DAC's carefully chosen by CJ especially for the dv2b. According to LJ, these chips have a very low distortion plus high sampling rate, plus used in conjunction with vacuum tubes, the sound is closer to analog rather than a typical digital sound, why it sounds warmer than most CD players out there...

CJ gave up on repairs with these units over a decade ago, and allowed McCormak to take over their digital line of products under a special business partnership. Then the UDP1 was introduced by McCormak and later on another CD player by McCormak. However, since these items were both made under the same factory as CJ's line, the owner could request for either of these units to be fitted with the CJ logo rather than the McCormak logo.

Basically at the end of the day, if you require repairs or service, you would have to take the unit to a qualified tech who is familiar with high end gear. I also had the circuit diagram at the time but goodness knows where it is now, probably in someone's old cupboard!

CJ will no longer perform repairs on this unit simply because they have moved on and many of the vintage items made earlier aren't available on file, hence they have no reference of. If you can get hold of the schematic and get a tech to look inside, you'll be able to identify all the high quality parts, such as caps, power supply etc. The tubes used are available from other sources, it is the main transport unit and DAC's that would be hard to source.

Hope my reply helped, take good care of it as I felt it was one of the best digital playback systems I've ever used to date!
Cheers RJ

[pedalhead]

Hi RJ,

Thanks for the detailed post, much appreciated. A brief update on my Dv2b... It was dead on arrival, wouldn't read any CDs. I figured it must be the Philips 12.1 mechanism at fault (they are well known for being extremely unreliable).

I ordered a VAM1202, which is the current equivalent. Its a pretty easy job to replace it... a few screws and six wires to (de) solder. Unfortunately after I swapped them the player still wouldn't read any CDs .

I'll get someone more skilled to check it out sometime & will report back.

Cheers,

Mark.