Underwood is now selling Audio GD kit; amp, dac, headphone amp, ...
Here’s snippet from their R2R dac
The R1 is an R2R full discrete DAC that uses 8 groups fully discrete R-2R DA modules to combine into a real balanced push/pull decoder. it also uses 4 group fully discrete real balanced DSD native decoders. It uses a fully discrete real balanced current transmition design. Jitter is kept ultra low by using dual ultra high frequency 90/98 MHz Accusilicon 318B femtosecond clocks to a provide synchronous clock for the whole unit without using a PLL up-frequency. The R1 works up to 32bit/384K with DSD512 asynchronous USB transfer thru the Amanero 384 FPGA synchronous clock. The entire whole digital circuit is built with single FPGA and 5 CPLD programmable chipsets to separate the different configured circuits to avoid interrupting the data stream process in parallel mode. The unit supports firmware updates future sound quality updates and all digital process mode settings are accessible by buttons on the front.
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Hi Terry,
I was surprised you didnt mention the AM Tubadour SE in your Pagoda review. You described it as a giant killer a year ago (you probably didnt use that term) but now I see it's the Pagoda that is in your best products list.
I would really appreciate it if you could tell us how they compare. You write in the review the Pagoda needs to be used fully balanced to give its best. Would you say the AM is better for those of us with RCA pre/amps?
thomas |
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@georgehifi - agree but unless some of these people hear the differences in their own systems they will not know the difference.
I use the Soekris DACs in the DAC we offer along with a 30lb power supply!
Happy Listening |
I have the MHDT Labs Orchid, which I like very much. I also have an Aqua La Voce S3, which is also NOS R2R, and so far, my favorite DAC that I've tried. Having said that, not all delta sigma DACS suck. I really like the way my TEAC NT-505 streamer sounds. It has dual mono
AKM VERITA AK4497 dacs and is very neutral, revealing, and easy to listen to. A little on the "warm" side like the Orchid, but more detailed, but without the hard digital edge that many delta sigma DACs seem to have, especially (IMHO) the Sabre based DACs. |
I had two MHDT dacs over the years.
Wonderful and natural. SUPER value. |
However, it’s a different kind of chip than delta-sigma DACs. Yes Delta Sigma (DS) is not R2R, it took the place of R2R chips because it was far cheaper to make and it could do sacd and dsd. But to me it (DS) can’t do PCM Redbok 16/44, 24/96 or DXD "bit perfect" like R2R' can, it can only give a "facsimile" of it Cheers George |
The Pagoda has a chip - it's the PCM1704 R-2R. However, it's a different kind of chip than delta-sigma DACs. |
Can a R2R DAC also have a chip? I am as usual confused.
R2R chip dacs were the old obsolete PCM1702 PCM1704 TDA1541 etc etc, all were stopped being made because the laser trimming of the microscopic R2R resistors, it was too expensive and time consuming for a chip to be sold for $20 They went for delta sigma because it was far cheaper and no laser trimming involved. Today we have R2R back again but this time discrete normal size resistors that are even better matched today without doing anything to them, all good for the sound of digital. Cheers George |
Can a R2R DAC also have a chip? I am as usual confused. |
I will be checking out an SWx1 Dac ii special next week. Hope it sounds as good as they say. |
That's good, I thought being new it would be discrete R2R, I was referring to the new era of killer "discrete" R2R dacs available now, that MSB championed first off the rank over 10 years ago.
The Texas PCM-1704's chips in Mhdt haven't been made for over 7 years now, they were the last and arguably the best of R2R "chip type" d/a converters made though.
Cheers George
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Hey George,
If you read the details presented by the designer regarding the design in the review, you will see that the Balanced Pagoda doubles the DAC chips and circuit for a true not pseudo design. |
Real "Discrete" R2R dacs, need twice as many R2R resistors as discrete R2R single ended ones. This is where the expense is. Many just have pseudo single ended to balance opamps on the analogue output stage to get balanced output, so really your better off just using the single ended output unless you want to run 3mt+ interconnects. Ask the manufacturer if the discrete R2R resistor DtoA stage is also balanced, or just the analogue output stage. From Soekris Audio http://www.soekris.dk/ they have some of the best R2R dacs, here is the difference between their "single ended" and "real balanced" dac boards. Single Ended https://ibb.co/V2hR2Y7True Balanced https://ibb.co/hB1Ff1yCheers George |
