R2R Ladder DACs or All in One Streamer Solutions

Formed in 2002: Music Heaven Development Team (MHDT):

ABOUT THE BRAND, old article. Still in business in 2020.

The gang of four founded Mhdt Lab in 2002 and are known as: ‘"Music Heaven Development Team".

They had decided to begin designing DACs to bring the feeling and fun back to digital. Motivated by the shortcomings of most DACs to faithfully convey, with spirit, varying styles of music, they have successfully created affordable great sounding and flexible little gems. Asynchronous and synchronous inputs, BNC, USB, RCA, and Toslink. The best of R-2R Burr-Brown PCM56P-J DACs, and a single NOS GE5670 vacuum tube buffered output stage in its circuit design brings the soul into the digital realm.

“‘Less is more’ is still the major rule we follow in our designs. By using the PCM56P, and due to its current output, we can omit the use of amplification (the op-amp), which provides a purer signal than can be achieved with a more complicated circuit.”

Along with Burr-Brown PCM chips, the Philips TDA1541 series chips were imbedded into the mhdt designs as being another 16-bit chip that produced a very musical and enjoyable result. More bits isn't always better. 

More bits isn’t always better.

Correct, RedBook, 16/44, 24/96, or DXD, done with R2R Multibit and done right is "Bit Perfect", where DS (Delta Sigma, 1-Bit, Bit-Stream, Single Bit), is just a facsimile. But it does do DSD, but then there a few discrete R2R Multibit dacs out now that can also do DSD now.

To me the best Delta Sigma dac chip I’ve heard doing RedBook, was one that used a Delta Sigma Burr Brown dac chip in a YBA Dac and Shanling CD , but it was a Hybrid, having the first 4 bits as multibit but the rest taken over with Delta Sigma, that was the Burr Brown PCM1794 or 94 or 98?

It seems to me that TI (Texas Instruments/Burr Brown) with their later dacs "are coming about face" to R2R again and doing these 4 bit Hybrids, instead of their full Delta Sigma PCM1738 etc, as to do full R2R (eg PCM1702/1704etc) is going back to very high costs again because of the manufacturing of them eg: laser trimming all those R2R resistors.) Where doing 4 bit is not too expensive but gives increased sound quality.

Cheers George

Actually those classic cars do get trounced by modern designs in virtually every aspect. Acceleration, handling, top speed, fuel economy, rel world handling over uneven surfaces. You name it. It's not even close.

A classic car does not get "trounced" by a modern piece of junk. Indeed, it becomes "classic" not just because people are sentimental but because of design.

Look at something as simple as  Tesla Model-3 Dual Motor Performance. There isn't a standard production 911 pre-2010 that can beat it 0-60 or in the quarter mile. Those are relatively modern 911's, never mind Classic. Nothing front engine production even comes close due to lack of traction.

Modern performance production road cars are pushing 1.2g on road rated tires. In 1990, barely old enough to be a classic, the best production car hit 0.94g.

Today's base Mustang with the little 2.3 Ecoboost runs a 5.1 0-60, and with typical incentives that's off the lot for $25K + taxes.  In 2000, only the SVT Cobra could beat it and that was $55000 then, a lot more in today's dollars.

I can't think any measure that cars in the past were superior, except ease of repair, which was good, because you did that a whole lot more.

Correct, RedBook, 16/44, 24/96, or DXD, done with R2R Multibit and done right is "Bit Perfect", where DS (Delta Sigma, 1-Bit, Bit-Stream, Single Bit), is just a facsimile. But it does do DSD, but then there a few discrete R2R Multibit dacs out now that can also do DSD now.

They absolutely are not bit-perfect. They have non-linearities, settling time issues, flicker noise, etc.  They are just simpler to understand than sigma-delta. At the end of the day, all that matters is that the analog waveform that comes out looks like the one that went in.  Getting hung up on data converter architecture is silly unless you specifically want the artifacts that come with that technology.

To me the best Delta Sigma dac chip I’ve heard doing RedBook, was one that used a Delta Sigma Burr Brown dac chip in a YBA Dac and Shanling CD , but it was a Hybrid, having the first 4 bits as multibit but the rest taken over with Delta Sigma, that was the Burr Brown PCM1794 or 94 or 98?

It seems to me that TI (Texas Instruments/Burr Brown) with their later dacs "are coming about face" to R2R again and doing these 4 bit Hybrids, instead of their full Delta Sigma PCM1738 etc, as to do full R2R (eg PCM1702/1704etc) is going back to very high costs again because of the manufacturing of them eg: laser trimming all those R2R resistors.) Where doing 4 bit is not too expensive but gives increased sound quality.

The PCM1738 is a segmented DAC (TI Advanced Segment DAC) as has been probably almost every single IC based sigma delta converter for audio in the last 20 years. Using a multi-bit modulator allows for much better practical implementations of SD audio DACs.

Ok, do not know now? Was kind of liking my tubed MHDT Orchid. Maybe I should like? Maybe I should not? My ears are still deciding, for 4 months now. So far it is one of my favorites. My ears will decide. Enjoy!