Twisted Pear Buffalo III DUAL MONO DAC Build

[SCompRacer]

My LCD shield arrived from the Netherlands so I was able to tidy up the display portion of my DAC project. The shield or PCB just required some header pins added to plug it directly into the Arduino UNO board and for harness connectors. Three harnesses connect the LCD, rotary encoder and IR receiver for the remote. Another harness (seen in the fourth picture) connects to the DAC board. You can see how the shield makes for a much neater install.

Other components mounted on the shield are the level converter that drops 5v down to 3.5 for the Buffalo III I2C (two wire serial control) header. Also on the shield is a MCP42010 two channel digital resistor to control LCD backlighting, also via remote. Up a couple of posts I had already added the I2C control of the LCD which makes for a significant reduction in wires to the LCD screen.

I got the shield from CE-designs and it ran me 5 euro or $6.47 plus postage.

http://ce-designs.net/index.php/shop...-shield-detail

Aside from some fine tuning on the code, getting a nice enclosure is up next. In the final build, I'll add a USB cable/input so I can program the Arduino without removing the cover.

[tonyb]

Nice work Rich, again. Your one of a few that put as much effort into squeezing every last drop of SQ from your digital as you do your analog.

[agfrost]

That's a nice way of saying it, Tony. One could also say "Geez, Rich, you're somewhere in between "OCD" and "lunatic."

(I keed, I keed!)

[SCompRacer]

Your one of a few that put as much effort into squeezing every last drop of SQ from your digital as you do your analog.

And that is a good thing, right? Thanks Tony! The end is in sight. I decided on a hi-res USB to I2S module to try since the Twisted Pear hi-res USB module is yet to be released. My Netherlands connection has one and will report his findings. Many folks say due to the DAC chip design, you don't as big a boost in SQ going from SPDIF to I2S input.

That's a nice way of saying it, Tony. One could also say "Geez, Rich, you're somewhere in between "OCD" and "lunatic."

(I keed, I keed!)

Funny man! LOL Jay, I guess some might believe that. As Shaw said all progress depends on the unreasonable man.

Working with modushop is great so far. They are in Italy...I get this email from Andrea about my plans...Hey! Wassa mattu u? Stupidio!

[strider]

And that is a good thing, right? Thanks Tony! The end is in sight. I decided on a hi-res USB to I2S module to try since the Twisted Pear hi-res USB module is yet to be released. My Netherlands connection has one and will report his findings. Many folks say due to the DAC chip design, you don't as big a boost in SQ going from SPDIF to I2S input.

Which USB converter did you go with?

[tonyb]

Eh guys...you know the score. Every so often we get someone who wants their Iphone or computer music plugged into a 300 buck avr to sound as good as their 2 channel analog system and give up while proclaiming digital sucks. Call me old fashioned, but I still remember all the tweeks and junk we tooled around with to squeeze out that last drop of SQ from our analog stereo gear. It's just refreshing to see that same passion in the digital world. Something Rich has in spades.

Carry on.....still can't wait to get together with a bunch of you goons for a cocktail and a listen.

[SCompRacer]

Which USB converter did you go with?

This one.....99euro, like ~$127 US.



http://luckit.biz/new/product/waveio/

The thread at diyAudio.

http://www.diyaudio.com/forums/digit...interface.html

Asynchronous 24/192, ASIO/KS/WASAPI/Direct Sound drivers for Windows XP. I haven't got it yet, will order next week. The enclosure was the priority right now. I was thinking of modding a Musiland USB DAC (similar pricing) but they use a packet transfer I'm not sold on versus asynchronous. And I'd have to solder tiny leads to the tiny PCB traces to extract I2S before the DAC chip like I did with the Denon. I have one side of a nice Twisted Pear LCDPS dual 5v linear power supply open in my DAC to power it.

If USB to I2S results in significant improvement to SQ, I could entertain the idea of the exaU21. Up to 384 kHz I2S and 352.8 kHz DSD audio in full 32 bit resolution. (The ESS Sabre DAC chip handles SPDIF differently than other DAC chips which results in less jitter and better SQ with the SPDIF signal). The exaU21 runs $430 though and will also handle DSD over USB. I'd have to sell something to fund that. The OT door got shut the other day at work.

http://www.exadevices.com/exaU2I/Overview.aspx



LOL Tony....Goons r us... Yet I still enjoy music from other sources, just not as much....lately the retro system with Polk 7A's has been getting lots of use.

[strider]

That exaU21 is really nice but I'd have to sell something also, like an organ. Hadn't seen the one you went with, although I've seen the thread on Diyaudio. It seems pretty similar to the one I am considering from Minidsp, their USBstreamer. I currently am using their ministreamer, but it doesn't support anything above 24/96 and it is isosynchronus.

[SCompRacer]

I missed that one...

There is another one, the Amanero. $97 US. OEM Combo384 Module - USB class 2 to I2S 32bit and DSD output Converter.

http://amanero.com/



Thread at diyAudio.

http://www.diyaudio.com/forums/vendo...converter.html

If you haven’t already, check out HiFiDuino. While navigating his blog is difficult (for me anyway) he is always trying different USB solutions (along with modding them) and even provides measurements. He is the one that first wrote and made the Arduino code available to all for the Buffalo II DAC. He gave lots of folks a start that wouldn’t of had a chance to get I2C control of the Buffalo DAC.

http://hifiduino.wordpress.com/category/diy-hifi/

[SCompRacer]

Another interesting diy USB offering is Ian's asynchronous I2S and S/PDIF FIFO KIT. ~$149 + depending on options.

Thread at diyAudio.

http://www.diyaudio.com/forums/group...ml#post3093337

Lots of intersting things going on in the digital DIY world! I think all this effort led to exa building a DAC based on the ESS Sabre32 that does asynchronous USB from 44.1 to 384Khz at 32bit resolution, and DSD at 2.82 and 5.64 MHz. $2,500 ducks IIRC, with a 30 day free trial.

http://www.exasound.com/e20DAC/e20DACOverview.aspx

That is what I basically wanted and built, although I went with shunting power supplies. As a wise man once told me Twisted Pear has strived to optimize each performance area for max sound quality. The DAC chip itself has four high quality regulators which is rare. It appears the exa DAC has an external PS. Not sure if it is a wall wart or not.

[strider]

That exa DAC is pretty nice looking, what a shame it would be if it were powered by a wall wart.

This one your building is off the charts, though. The products that Twisted Pear offers are first rate, but your implementation of their stuff really makes it shine. It's inspired me to re-do my DAC. Each section of the DAC will have an independent transformer and power supply in a case seperate from the DAC board, new USB interface, re-wired etc. The power supplies I purchased from a group buy on diyaudio.com, they're designed by poster Salas on there. The DAC board is a demonstration board for Burr Brown DAC chips, I have a PCM 1792. Fred was gracious enough to karma the board a while back. It'll definitely be a step up in performance, but not like this dual mono monster!

[bikerboy]

Hi Guys,
I just received the Amanero usb to i2s converter. I was able to get it via a GB on diyaudio for about $60. It sounds much better than the Teradac terelink usb module it replaced. I have a single BuffaloIII not the dual mono monster Rich has created. The pc is sounding better than ever. A Cardas usb cable that I bought here on the forum also improved the sound much to my surprise. I think the new AVCC/Trident combo is next on the list for me. Now I need to figure out how to get some 384khz music to test out this new usb device. Fun stuff!

[SCompRacer]

Hey Ben, glad to hear I inspired something in a good way Thank you both for the kind words.

Those Salas power supplies are top notch. Fred uses them in his BIII build. He was very clever and used the chassis floor as a heat sink. Fred was the one that reminded me of Twisted Pear when I looked for an even better DAC after the Music Hall 25.3 mods.

I was considering separate enclosures for power supplies but have been careful about wiring and placement. I am real fussy about a low noise floor and still have it. One of my tests is to crank the volume full tilt with no music playing and I still have no hiss or hum from speakers. Therefore I decided on a large enclosure to keep the spacing as is.

In the final assembly, I will implement some shielding between the toroidals and DAC boards. I have seen folks with dual mono builds use a smaller chassis using less transformers. I wanted to maintain galvanic isolation between the two power supplies that could have shared a transformer and stayed with the six. Two feed linear supplies that power the Arduino/LCD (12v) and Sidecar/Teleporter modules (5v) and future USB module. I wanted that LCD with its own PS as they can add noise. I used a star or single point ground for all power supplies and boards. That ground is isolated from chassis ground.

If I had to assign a SQ percentage to the dual mono BIII versus my single build, it would be ~15%. The big boost was in channel separation and increased detail. That common statement of hearing things you didn?t notice before applied. But quite an expense to get that improvement.

Ironic, but my love of analog funded this DAC project. I had much less invested in the Lenco build than my Nottingham Space 294 with speed control was worth. I liked the Lenco better and sold the Space 294, which paid for my digital fix.

[SCompRacer]

Hi Guys,
I just received the Amanero usb to i2s converter. I was able to get it via a GB on diyaudio for about $60.

Wow, I missed that. Great deal for you, sonically and cost wise! It is like $100 now. Lots of great USB choices out there in the $100-$150 range. My USB module may be delayed a bit due to enclosure costs. That machining really adds up! Modushop has been great to work with. English is a second language for them so pictures and a precise front panel express file are very important.

[SCompRacer]

This weekend I added LCD backlight control and temperature monitor accessible via manual encoder and remote control.

http://www.youtube.com/watch?v=GWaBTpUBWgo

The custom LCD shield had a header for some LM35 temp sensors, so why not. I think it's a wrap. (Although my bud in the Netherlands added day/date/time clock to his). Na, I'm done.

The enclosure is finalized with some added machining to the rear of the 10mm thick front panel. I added a cavity in rear side to move the LCD screen closer to the front side. A 45 degree chamfer was also added around the outer edge of LCD opening. It will be a couple weeks or more before I get it (modushop is in Italy).

I've had some challenging and frustrating moments with the code, but am glad I stuck with adding the I2C control with display.

[chumlie]

Nice work. Mad skills you have there. Also thanks for the link to lencoheaven. Lots of good reading.

[bikerboy]

Hi Rich,
They are starting another GB on the Amerano. It does sound very good and easy to get working well. I am using the usb for power and it sounds great. I will make a 3.3v ps and see if it helps. Nice work the the dual mono Buff. I've thought about the arduno but think it is over my head. Thanks for keeping us in the loop.

[SCompRacer]

Nice work. Mad skills you have there. Also thanks for the link to lencoheaven. Lots of good reading.

Thanks! Lenco Heaven is a great place!

Hi Rich,
They are starting another GB on the Amerano. It does sound very good and easy to get working well. I am using the usb for power and it sounds great. I will make a 3.3v ps and see if it helps. Nice work the the dual mono Buff. I've thought about the arduno but think it is over my head. Thanks for keeping us in the loop.

Hey, thanks for the heads up! I added my name to the now GB III list.

Have you been following glt's blog and the $10 bit clock re-clocking mod on the Amanero using the Potato Semi flip-flop chip? Looks very mad scientist but he did achieve some impressive results.

http://hifiduino.wordpress.com/2012/...cking-results/



Once I try USB>I2S with the Amanero module and if it proves significant over SPDIF, I'd have to redo my PC based setup. Like with a mini PC controlled by touch pad or smart phone. I've yet to open up the SB Touch and mod it to export I2S. The folks that have done it report modest to great gains. Multiple I2S and DSD sources will have me adding some creative switching too..it just never ends...more code......

The Arduino isn't too bad once you get immersed in it. I made it even more complicated by adding features. Nice to have total control at your fingertips rather than open up and make dipswitch settings. Arduino and code really hurt my brain at first but now it has subsided into a dull ache. It's not too expensive with an UNO going for ~$30 and a 4x20 LCD ~ $15. A rotary encoder runs a few bucks (HiFiDuino does list products he used suggestions). Adding an Apple remote another $20. Highly recommended add on is the I2C LCDextra IO board. ~$8.50 US. Assembled to either blue or green LCD, ~$20.32 US. You do have to add a couple lines of code and download their lcd library to replace the Arduino lcd library or it won't work.



I2C serial control results in a significant reduction in wires to the LCD. Adding the custom shield like I did makes it even neater. 5 euro, ~$6.38.

http://www.electrofunltd.com/p/i2c-l...-extra-io.html

http://www.ce-designs.net/index.php/...-shield-detail

Then download the free code from HiFiDuino and modify for your application. Help is available out there in the DIY world. I plugged mine into a wallwart PS and tested the code before connecting it to the BIII. That will show if you can access menu items and select different sources.

http://hifiduino.wordpress.com/code/

Follow HiFi Duino's illustrated step by step there.

http://hifiduino.wordpress.com/intro...-to-hifiduino/

The code was originally written for the BII so you have to mod it for a BIII if you have multiple input sources. Corpius made his BIII add on code public here.

http://www.ce-designs.net/index.php/...nput-selection

If Twisted Pear ever releases their control, I am guessing it will be a lot easier to implement as Russ has programmer skillz. Corpius is also working on an I2C controller here.

http://www.diyaudio.com/forums/digit...ontroller.html

Despite the pain I have enjoyed this project very much. I thought I knew a lot about digital before....yet I have learned so much and there is still more to know. The DIY world is striving to get the best out of digital. Glad I got on board.

[FTGV]

Hey Rich did you get your replacement micro board to operate the relay string on your sidecar correctly?

[SCompRacer]

Hey Rich did you get your replacement micro board to operate the relay string on your sidecar correctly?

Hey Fred. Yes I did. I had changed to a lower value resistor on the Sidecar board so it could be activated by the low voltage TP manual selector board. I forgot about that in the move to Arduino control, and it exceeded the 40ma of the UNO. I could still use it on a build that doesn't require a Sidecar. There are also other pins available to go to, but I didn't try any of them.

[SCompRacer]

Hardware debounce added to my rotary encoder. Hardware debounce results in less noise versus software 'in the code' debounce. I find you get less ghost changes and overshoot with hardware debounce too, or I am just getting better at turning the knob.... With the remote I rarely use the manual encoder anyway.

My front panel is machined and heading off to anodizing! It should ship next week. Modushop in Italy is doing the work. The main reason I went with them is looks, machining options and cooling options for this hot running DAC. They offer a fully drilled base to mount components on, and fully vented top and bottom panels. I had a rear panel cavity added to move the LCD closer to the face of front panel.

http://www.modushop.biz/ecommerce/index_l2.php

[SCompRacer]

Oh, when I said less noise with hardware debouncing, I meant in the circuit for the Arduino controller. There is no noise that makes it way to the speakers turning the encoder with software debounce.

[FTGV]

That front panel looks incredible.Oh and noise free switching is always nice.

[SCompRacer]

That front panel looks incredible.Oh and noise free switching is always nice.

Thanks Fred! I like showing the pic of the front panel to my wife. She says "Oh honey, it's so big!"


This image shows a .7 milliseconds bounce from an encoder after it is turned and stop. The caps/resistors are suppose to fix that. Bourns says so!



From the HiFiDuino site.

http://hifiduino.wordpress.com/2010/...w-no-debounce/

[schwarcw]

I like showing the pic of the front panel to my wife. She says "Oh honey, it's so big!"

LOL! That's funny!


Man that case looks fantastic. It will look great anodized black with color letters!

[SCompRacer]

Hey Carl! I'll try your suggestion of water based latex instead of enamel on a test piece. The enamel sounds scarier, so you know where I?m likely to go?

Hi Rich,
They are starting another GB on the Amerano.

11 to go....getting kind of anxious.

https://docs.google.com/spreadsheet/...wYS1EcXc#gid=0

I have one half of an adjustable dual linear PS open. I was considering changing some parts on it to get the voltage past 6.5v and use it on the Arduino, but I think it best to keep the controller with LCD separate of the modules I am powering with the other half of the PS.

What software are you using? foobar? JRiver?

[SCompRacer]

Tonight on Void-Your-Warranty SCompRacer disassembles his SB Touch to perform an I2S out mod. I2S separates clock from data and can sound better than SPDIF via coax out. It does sound a bit better, but not a whole bunch. Part of that is due to how the ESS Sabre32 DAC chip handles SPDIF. Decoding is done using a method that does not require an explicit measure of the clock frequency. The best way to do this mod is perform an external clock mod to the Touch with I2S out. A Twisted Pear Teleporter (LVDS or Low-voltage differential signaling module) like used in the Denon transmits the signal to my DAC.

[FTGV]

Brave little fellar aren't we.Your certainly covering all the bases.
Agreed going IS2 would likely prove more benificial with a DAC that needs a separate SPDIF reciever chip,such as the cs8416,instead of the Sabres integral SPDIF reciever and it's time domain jitter reduction.

[SCompRacer]

Brave little fellar aren't we.

Yup, considering that since they have been discontinued folks are asking from $400 to $1K for the Touch on ebay.

I'm very pleased with the SPDIF via coax so far on this DAC. I see myself moving to a USB via PC due to no limitations of hi-res and DSD files I can play (384KHz to 2.8MHz +). I want DSD over USB, not dithered down to PCM. Lots of modules to choose from and they are getting better. I'm sure JRiver is in my future when I go that route.

As you know ESS Sabre is one of the DAC chips where I2S and DSD share some inputs. The Amanero USB module does DSD and HiFiDuino is using foobar to fix the R and L channel swap in DSD. I have no problem adding another OTTO II, or two of them, to switch between I2S sources inside the DAC. I'll just write more code to handle the switching for the appropriate inputs, or just use a mechanical switch on the back like I did with the Denon.

[SCompRacer]

My DAC enclosure has arrived. Shipped from Hi-Fi 2000 / Modushop in Italy 11/28, arrive 12/5!

http://www.modushop.biz/ecommerce/index_l2.php

It is a Pesante 3U, 10mm front panel, 450mm (17.7" wide front panel, internal 17.12") x 400mm (15.78" deep) x 120mm (4.7" high). Add ons were both sides front panel machined, engraved, anodize after machine, drilled inner base, 29mm shiny knob, fully vented top cover and four of their anti vibration feet. I went Hi-Fi 2000 due to the cooling options. Note the drilled base to mount boards on and while not pictured, I opted for a fully vented top cover.

I added a cavity in rear of panel to move the LCD closer to the face of front panel. Andrea also drilled and tapped holes for mounting the LCD and they are spot on. Machining and finish are high quality. Andrea was very helpful to work with. (Good thing I didn't flirt or ask for pics cause I learned Andrea is a guys name in Italy). I can only hope to do as well mounting the Arduino control board. The opening around the LCD is chamfered. No ink fill of lettering as they only use black ink, which is not much use on a black face plate. We shall see how I do with the front panel paint fill of lettering and Twisted Pear logo like ModWright did on his optional Black/Blue SWL/SWLP faceplates.

Lots of work to do!