DIY TDA1541A PCB "D3"

[chromenuts]

@Mark Thanks for chiming in towards the end to help me sort out the final bits!

@Ben Thanks for the information on the wire. There is still an eBay seller in Bulgaria that is offering a variety of gauges in the Isotan Constantin wire.

Some listings are describing the wire as “oxidized” ...just wondering what that is all about as I thought something like this would have an enamel coating or similar. I’m assuming it has some sort of coating. Part of the description gives the resistance per meter.

 

[ryanj]

HI Nilton,

So, could you consider D3 design as a Direct Interpolation DAC?

No, IIRC Direct Interpolation was a type of over sampling but done in the analogue domain.

Only output transformers instead of tubes? I really like to try a Lampizator 6N2P tube stage... Have you ever tried this?

Yes i've tried this tube stage and it sounded fine, but I couldn't recommend a high voltage OP stage - too much risk involved for a newbie - unless of course you have had experience with high voltage...

Transformer IV is great - no power supplies, sound great, and only require one cheap resistor. Member bisesik on this forum makes very nice transformers for a good price. Ivan has recently been playing around with the TDA15451A and has specially made transformers to suit the 1541A. Nanocrystalline core, very low DCR, excellent frequency response and low losses. At 20Hz with a 10k load resistor its only down -0.6dB and im getting around 3.7Vpp into my F5 which is enough for my speakers to give a decent thumping bass and annoy the neighbours.

I did not find so many players/transport units with i2s outputs, and I need a versatile dac so that I can switch it from transport/streamer to TV, to PC and also to my cell phone by bluetooth. Is it possible to have I2S, SPDIF, USB and Bluetooth inputs? If it is possible, SIM would be used only when I2S input is selected?

Have a search for USB to I2S convertors.

What Is everyone else using? Im still using an old WaveIO connected to my laptop running jriver, spotify and tidal.

 

[ryanj]

I've still got a lot of CuNi44 if you want some.

ENAMELED CuNi44 0.1mm diameter (Constantan, Isotan) Resistance wire

@Mark Thanks for chiming in towards the end to help me sort out the final bits!

@Ben Thanks for the information on the wire. There is still an eBay seller in Bulgaria that is offering a variety of gauges in the Isotan Constantin wire.

Some listings are describing the wire as “oxidized” ...just wondering what that is all about as I thought something like this would have an enamel coating or similar. I’m assuming it has some sort of coating. Part of the description gives the resistance per meter.

 

[manniraj]

A noob question and sorry if this has been answered somewhere in this long thread, what is the difference between the V1/V2 of the i2s2sim boards? Is the V2 just the latest version with more components compared to V1 as far as the pricing goes both the PCB boards are at the same cost.

Thanks

 

[ryanj]

A noob question and sorry if this has been answered somewhere in this long thread, what is the difference between the V1/V2 of the i2s2sim boards? Is the V2 just the latest version with more components compared to V1 as far as the pricing goes both the PCB boards are at the same cost.

Thanks

V1 is the original circuit ecdesigns shared.

V2 has extra outputs - 4 x LE, 4 x BCK, 2 x DL, 2 x DR, 2 x DR inverted, and 2 x DL inverted. Adding the extra outputs and inverted data outputs enables balanced operation. I have tested a total of 4 x D3 PCBs being run at 176k sampling rate in balanced mode.

So the V2 is better value with the extra functionality. But with the V1 you are getting the original shared circuit from EC.

 

[manniraj]

Thanks Ryan.

 

[ryanj]

HI Nilton,
No, IIRC Direct Interpolation was a type of over sampling but done in the analogue domain.

Correction - Direct Interpolation is very similar to Linear Interpolation

Hi, Uchi Deshi

Thank you for your reply

Direct interpolation uses at least 2 DAC's, this creates 88.2KHz virtual sample rate and doubles the resolution. The Quad Direct Interpolation DAC creates 176.4 KHz virtual sample rate and results in 18 bit resolution. And yes sure you can use more DAC's in parallel, 8 DAC's will create 352KHz virtual sample rate and so on. How does it work? It involves slight timeshifting (delay) of both Data and Wordselect and connecting 2 pair of DAC outputs in parallel, then these two are fed into a differential amplifier after I/V conversion. So this system only needs 4 I/V converters. The easiest way of visualizing this system is comparing a 1 cylinder engine with say a 4 cylinder engine. The 4 cylinder engine runs much smoother and achieves much higher revs than a 1 cylinder engine would. Now the DAC's are the pistons, the crankshaft is the output stage and the ignition is the timeshifting. So all 4 DAC's receive their DATA in sequence (not simultaneously). So they output their sample on slightly different moments in time (one clockpuls after wordselect changes) and thereby creating addittional interpolated steps i.e. increasing the resolution. So basically it's a quite simple technique. Since an added sample always stays in the timeframe (64 clockpulses) of the original (large) sample, there is no phase shift. Schematic diagrams will follow.

 

[chromenuts]

Hi Ryan

I was thinking about ordering some of the Constantan wire to try making some iv resistors...I’ll PM you to discuss it.

I finally finished up the casework and got a lid on the D3. I took a bit of time rearranging my system to try and have my digital front end organized nicely.

It’s been probably about a year of planning and building to get here and finally be able to sit back and enjoy it.

I have been enjoying it a lot over the holiday weekend here.

I’ve attached a few pics of it and the rack (I hate the rack and it needs a proper replacement...sooner or later).

I am using a rebuilt Mac Mini to stream from iTunes with an App called Bitperfect that loads the music into RAM for playback and prevents the OS from messing with the file resolution. It has a few glitches now and again, but I can live with it for now.

One of the best decisions I made was to buy a Luna Display dongle to interface my Pro Pad with the Mini. It has been seamless and completely stable. It allows me to run the Mini headless and have complete control over any software I would want to use on the Mini from my Pro Pad.

I’m also very happy with the Shigaclone project. It sounds great and allows me to just throw in any disc I have been too lazy to rip because I’m busy trying to download new stuff all the time.

I will be going back into the D3.

I’ve a slightly used pair of bisesik’s transformers I negotiated a deal on.

My understanding is that they are wound optimally to be used with a pair of TDA1541A in differential mode.

I’ll need some guidance with the wiring most likely.

 

[ryanj]

Hi Kevin,

Well done, case looks awesome! You're whole setup looks very nice indeed.

What ratio transformer are you getting from Ivan?

Hi Ryan

I was thinking about ordering some of the Constantan wire to try making some iv resistors...I’ll PM you to discuss it.

I finally finished up the casework and got a lid on the D3. I took a bit of time rearranging my system to try and have my digital front end organized nicely.

It’s been probably about a year of planning and building to get here and finally be able to sit back and enjoy it.

I have been enjoying it a lot over the holiday weekend here.

I’ve attached a few pics of it and the rack (I hate the rack and it needs a proper replacement...sooner or later).

I am using a rebuilt Mac Mini to stream from iTunes with an App called Bitperfect that loads the music into RAM for playback and prevents the OS from messing with the file resolution. It has a few glitches now and again, but I can live with it for now.

One of the best decisions I made was to buy a Luna Display dongle to interface my Pro Pad with the Mini. It has been seamless and completely stable. It allows me to run the Mini headless and have complete control over any software I would want to use on the Mini from my Pro Pad.

I’m also very happy with the Shigaclone project. It sounds great and allows me to just throw in any disc I have been too lazy to rip because I’m busy trying to download new stuff all the time.

I will be going back into the D3.

I’ve a slightly used pair of bisesik’s transformers I negotiated a deal on.

My understanding is that they are wound optimally to be used with a pair of TDA1541A in differential mode.

I’ll need some guidance with the wiring most likely.

 

[chromenuts]

Thanks Ryan...here is a pic from the listing.

I’m not sure what all the info on the top line is about.

The bottom line indicates 0.5 + 0.5:22

 

[tubo]

HI Kevin,

here is a diagram for bisesik's transformer. hope this helps

you can find it here on podt # 430 Output transformers for DACs

 

[chromenuts]

Hi Ivan

Thanks for the link...I had seen that information before when I was first researching the passive iv solution.

To be honest, I get a headache trying to understand it.

I like to build these projects but I feel like I’m in over my head a lot.

Like they say, a picture is worth a thousand words. That is how I often figure this stuff out.

Regards
Kevin

 

[bisesik]

Hi guys,
I think that drawings will help Kevin to connect the correct way.

Output transformers for DACs

 

[har297]

Hi Ryan,

We were trying to procure components for this build, unfortunately, some of the components are not available.
Following are some alternatives that are available. Can you please let us know if these are fine ?

Original BoM -> Alternative
16MU226MD35750 -> ??
MMA02040C5109FB300-> MMA02040E5109BB100
MMA02040C5111FB300-> SMM02040C5101FB300
MMA02040C1001FB300-> CMA02040X1001GB300
MLFA25FTC1K50 -> SMM02040C1501FB300
MMA02040C3001FB300-> MMA02040E3001BB100

Thanks

 

[ggetzoff]

Digi-Key and Mouser have have the film caps in stock and you want a film cap here. The Rubycon product is the only one I know of that has the values correct size for the pads. Yes, the shipping will be a lot and the caps are not inexpensive, but look at this way, you are already saving a ton of $$ building a world class dac for low $.

https://www.mouser.com/ProductDetai...ivMdW89jzfQPpr%2BPYnHoWSyp8A2cuMwXnlx3g3MQA==

Blocked

16MU226MD35750 *Must be BOM cap*
MMA02040C5109FB300 MMA02040E5109BB100 (1/4w, find a .4mW)
MMA02040C5111FB300 SMM02040C5101FB300 (1/4w, find a .4mW)
MMA02040C1001FB300 CMA02040X1001GB300 (yes)
MLFA25FTC1K50 SMM02040C1501FB300 (1/4w, find a .4mW)
MMA02040C3001FB300 MMA02040E3001BB100 (1/4w, find a .4mW)

Mouser has all of the resistors in stock, so just order these resistors from them with the film caps.

Where are you ordering from?

Cheers,

Greg

 

[ryanj]

Hi Ryan,

We were trying to procure components for this build, unfortunately, some of the components are not available.
Following are some alternatives that are available. Can you please let us know if these are fine ?

Original BoM -> Alternative
16MU226MD35750 -> ??
MMA02040C5109FB300-> MMA02040E5109BB100
MMA02040C5111FB300-> SMM02040C5101FB300
MMA02040C1001FB300-> CMA02040X1001GB300
MLFA25FTC1K50 -> SMM02040C1501FB300
MMA02040C3001FB300-> MMA02040E3001BB100

Thanks

Hi har297,

Some of those alternatives may be ok, but as Greg mentioned there is no suitable alternative for the 22uF film cap - This is a critical part that is responsible for the depth and dynamics of the sound, especially the accuracy in the bass.

I would suggest getting all your parts from Digikey - they have 350 16MU226MD35750 in stock. Mouser also started stocking these caps but at a slightly higher price in low quantities - they have 90 in stock.

 

[har297]

Thanks Greg and Ryan,

Will search accordingly,

 

[ggetzoff]

To the group,

I just finished writing a build guide for the D3 board and sent it to Ryan for review. Once reviewed I will post it here.

Cheers and Merry Christmas,

Greg

 

[Vunce]

Thanks Greg, I’m sure the manual will be a valuable asset for assembly and startup.
Merry Christmas

 

[har297]

Thanks Greg,

It will help a lot for this build, especially because of intimidating SMD's !!

Merry Christmas..