Filter brewing for the Soekris R2R

Not even a tiny bit of clipping? Or have you reduced volume?

I set filter as F7 which is supposedly NOS. Listened to one or two songs, sounded alright.

I am very new to this digital filter thing, my interpretation of “clipping” is sharp cut-off at certain frequencies. If this is the case, then I will need to listen to it again and pay more attention this time.
 
Commenting to leave a mark. I spent the last couple of weeks reading this thread while I wait for a 1541 to arrive past grabbing one backordered from the spring sale.

I throw my deepest gratitude to the filter contributors. You know who you are (and who you will be). I'll watch for advancements as long as my Soekris DAC functions. I expect it to be an end-game DAC for the time being. At least until something truly significant comes along that I'm certain can justify investing in a move forward.

I've obtained a recommended USB-to-TTL cable and dimming film to cover the overly bright displays. I'm anxious to get TNT's latest comp running, so the preloaded filters probably won't last long. (Sorry, Soren. You apparently need to up your game as far as filter design goes. No offense.) I likely won't be trying to mod the hardware, although I am capable and I haven't yet looked into the other DIY threads. So, we'll see.

I must say, any of you who haven't read this whole thread owe it to yourself and the contributors to take the time even if you aren't capable of understanding the technical specifics. You'll get a better sense of what's involved and a greater appreciation for the guys who worked the math. When Paul disappeared into the ether there began a feeling of significant loss. Like the passing of a friendly acquaintance who had an extraordinary existence contributing to the good of society. :sigh: ...It would be nice to know he's doing well these days even if he couldn't be persuaded to come back into the community. I have to wonder what made him decide to close his blog.

Again THANK YOU to the contributors. :worship: :nod: :cheers:

Back to lurking, watching, and waiting.
 
Yeah, but shouldn't it be possible to allocate 1-2k taps from the FIR1 to FIR2, FPGA should be programmable, unless it's a.hard limitation of.the chip.

Sorry, the 16K luts FPGA also have limited resources........ And as FIR2 operates at higher speed, you can't just increase the number of taps....
 
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June 2019. Recently received a new DAC 1541 almost straight from Denmark, was backordered through the US distributor that went out as soon as they received them. Serial #224.

Using ExtraPuTTY per Randytsuch's blog and instructions with Soren's recommended FTDI USB-TTY cable. Discovered the 1541 came loaded with R1.21 firmware. Tried to load Spikestabber's latest filter pack, (post 1698) got the "incorrect image" failure. Then tried to load TNT's latest pack, (post 1700) which similarly failed. Rebooted, retried all, failed.

Interestingly the Soekris download page still has the R1.20 packs as latest available. Loaded it and then Spikestabber's pack, no further problems. Suggesting the obvious to current prospective and future users: Get your R1.20 from the Soekris download page now if you intend to use the above mentioned brewed filter packs. Before Soren updates the available to 1.21. Also, if you're a Soekris DAC owner I whole-heartedly recommend you shouldn't shy away from trying brewed filters in your DAC. It's easy as cake and just as easily reversible to the Soekris firmware/filters. (Provided you read the instructions.)

Preferred Spikestabber's pack due to excellent information from here. Beside Spikestabber's explanation for assembling the pack the additional information made his pack the ideal choice. (Sorry, TNT. I appreciate your efforts.)

That FYI or for your comments. Other than what's obvious...
 
That pack is tested good for anyone still on the fence, all samplerates work also. Tested using firmware 1.21.

Err. So why didn't 1.21 work for me? (I ask as if anyone actually knows.) I'm nearly certain I did nothing wrong when trying to install the packs. I didn't alter anything before having success with 1.20. Could it be specific to the 1541 firmware?
 
June 2019. Recently received a new DAC 1541 almost straight from Denmark, was backordered through the US distributor that went out as soon as they received them. Serial #224.



Using ExtraPuTTY per Randytsuch's blog and instructions with Soren's recommended FTDI USB-TTY cable. Discovered the 1541 came loaded with R1.21 firmware. Tried to load Spikestabber's latest filter pack, (post 1698) got the "incorrect image" failure. Then tried to load TNT's latest pack, (post 1700) which similarly failed. Rebooted, retried all, failed.



Interestingly the Soekris download page still has the R1.20 packs as latest available. Loaded it and then Spikestabber's pack, no further problems. Suggesting the obvious to current prospective and future users: Get your R1.20 from the Soekris download page now if you intend to use the above mentioned brewed filter packs. Before Soren updates the available to 1.21. Also, if you're a Soekris DAC owner I whole-heartedly recommend you shouldn't shy away from trying brewed filters in your DAC. It's easy as cake and just as easily reversible to the Soekris firmware/filters. (Provided you read the instructions.)



Preferred Spikestabber's pack due to excellent information from here. Beside Spikestabber's explanation for assembling the pack the additional information made his pack the ideal choice. (Sorry, TNT. I appreciate your efforts.)



That FYI or for your comments. Other than what's obvious...
Where do I find spikestabbers filters and info? Thanks.
 
Where do I find spikestabbers filters and info? Thanks.

The pack I used is in post 1698 in this thread. Page 170. They aren't really his filters but he did some important tweaks included in the post 1698 pack. Descriptions of the work are spread out through the thread as they were hammered out. It's a lot to read but it gives an idea of what's involved. There's a lot for a Soekris DAM or DAC owner to appreciate.

I'll add here that I chose Spikestabber's pack because he included Soren's Linear filter from the Soekris filters (F4 "red") which is important for well recorded music (no loudness wars compressed garbage) according to information I linked in post 1775. I'm assuming that Soren's filter is well advanced as linear brickwall filters go, although Spikestabber stated he included it so users could reference Soren's filter in comparison to Paul's best filters (the thread starter, Spzzzzkt) and a quasi-NOS filter in the rest of the compilation (not an exact quote). I expect Spikestabber will chime in with additional information when he sees activity here.