Sure, here are the details
Boss V1. I mod it according to the instructions manual to power it independently from the RPI.
RPI: 5V 3A SMPS (A generic medium quality one from an android box) soldered directly to the RPI.
BOSS: LT3042 chinese board + 15VA 6V transformer.
The Katana microcontroller is being powered by an IFI ipower with the negative side connected to mains ground and a 16000uF buffer cap close to the stack.
The Isolator is powered by a generic 5V 3A SMPS.
All this is fed directly to a MyRef rev C amp (another diy project) and then to my speakers: Tannoy Revolution XT8f.
Since most people think burn in helps, I refrained myself on comparison comments between Katana and Boss. But it is an upgrade, of course.
Worth mentioning that I am listening with the "Sound quality" output stage, I still have not tried the THD optimized version. I plan to do it this weekend.
Last edited:
Ktham,
I'm wondering how your Katana is sounding? I was looking for some comments I knew were posted earlier this summer for a post I'm working on and saw your power supplies waiting for a Katana. They looked good... can you give a description?
The Katana can sound VERY good with great supplies. I'm curious how others using good power are fairing.
Greg in Mississippi
Catching up on some old posts last night and this morning, I see some I SHOULD have responded to and didn't.
First, on the 'Smurf' sound... As Allo said, that was fixed by a firmware update that is in the lastest boards. AND the great thing is that those boards will also support updating firmware by the user! YAY!
I never saw any connection between dirty or bad inter-board connecting pins (on the Katana or RPi) and the 'Smurf' sound issue. I get it pretty regularly with the early firmware boards. In my experience, it would occur when I'd power down and power up quickly, even using the recommended sequence of 'DAC Board -> Microprocessor Board -> RPi -> [Output stage board (when using a separate +-15V supply)]'.
I found I needed not only to un-power / re-power the boards, but also sometimes reboot my LMS server (I'm running PiCorePlayer, which uses SqueezeLite as player software and requires a music server process running either on the RPi or on a separate computer. IMHO, separate sounds better, so I've stuck with that).
AND it also helped to give the Katana stack a few minutes to fully power down. Remember, Allo has .33F supercaps on their low-voltage power rails on this and several other of their offerings. That amount of energy storage will keep some of the circuitry powered for several minutes before finally draining. NOT giving it time to drain would sometimes result in the 'Smurf' sound recurring on power-up OR I'd get a flashing green light on the Microprocessor board indicating an issue.
I suspect it all had to do with initialization of the registers in the DAC, the Microprocessor, and the RPi (and the Katana driver) getting out of sync due to some portion of the the stack not fully powering down. Waiting, then repowering it all lets it reset them correctly.
Glad Allo addressed this in the firmware!
Then DimDim had a GREAT post on deemphasis:
I had said similar a couple of times to Allo in email coversations. I DO have some recordings with deemphasis... early Sheffield Labs as I remember. Back in the early 90s, I did a monster CD player rebuild based on the Audio Amateur Pooge articles. One thing I did was tap the deemphasis control line and use that via a driver circuit to lite an LED. Just as DimDim said, almost NONE of my CDs at the time and for as long as I used the unit (through the early 2000s) showed as needing deemphasis. WHILE one can use it to cut the highs for sonic preference purposes, that is not what it is for. AND if it helps all the time, that indicates some other issues that should be addressed.
Finally, I see I missed a post from wtnh correcting one of my earlier statements:
I found it worthwhile and would not use a Katana without it, just as I won't use the RPi as a source for any other DAC (RPi mounted or separate) with an isolator board in place.
THANKS for the catch wtnh... corrected it would read:
I found it worthwhile and would not use a Katana without it, just as I won't use the RPi as a source for any other DAC (RPi mounted or separate) without an isolator board in place.
Greg in Mississippi
First, on the 'Smurf' sound... As Allo said, that was fixed by a firmware update that is in the lastest boards. AND the great thing is that those boards will also support updating firmware by the user! YAY!
I never saw any connection between dirty or bad inter-board connecting pins (on the Katana or RPi) and the 'Smurf' sound issue. I get it pretty regularly with the early firmware boards. In my experience, it would occur when I'd power down and power up quickly, even using the recommended sequence of 'DAC Board -> Microprocessor Board -> RPi -> [Output stage board (when using a separate +-15V supply)]'.
I found I needed not only to un-power / re-power the boards, but also sometimes reboot my LMS server (I'm running PiCorePlayer, which uses SqueezeLite as player software and requires a music server process running either on the RPi or on a separate computer. IMHO, separate sounds better, so I've stuck with that).
AND it also helped to give the Katana stack a few minutes to fully power down. Remember, Allo has .33F supercaps on their low-voltage power rails on this and several other of their offerings. That amount of energy storage will keep some of the circuitry powered for several minutes before finally draining. NOT giving it time to drain would sometimes result in the 'Smurf' sound recurring on power-up OR I'd get a flashing green light on the Microprocessor board indicating an issue.
I suspect it all had to do with initialization of the registers in the DAC, the Microprocessor, and the RPi (and the Katana driver) getting out of sync due to some portion of the the stack not fully powering down. Waiting, then repowering it all lets it reset them correctly.
Glad Allo addressed this in the firmware!
Then DimDim had a GREAT post on deemphasis:
I had said similar a couple of times to Allo in email coversations. I DO have some recordings with deemphasis... early Sheffield Labs as I remember. Back in the early 90s, I did a monster CD player rebuild based on the Audio Amateur Pooge articles. One thing I did was tap the deemphasis control line and use that via a driver circuit to lite an LED. Just as DimDim said, almost NONE of my CDs at the time and for as long as I used the unit (through the early 2000s) showed as needing deemphasis. WHILE one can use it to cut the highs for sonic preference purposes, that is not what it is for. AND if it helps all the time, that indicates some other issues that should be addressed.
Finally, I see I missed a post from wtnh correcting one of my earlier statements:
I found it worthwhile and would not use a Katana without it, just as I won't use the RPi as a source for any other DAC (RPi mounted or separate) with an isolator board in place.
THANKS for the catch wtnh... corrected it would read:
I found it worthwhile and would not use a Katana without it, just as I won't use the RPi as a source for any other DAC (RPi mounted or separate) without an isolator board in place.
Greg in Mississippi
Greg,
You nail it. I tried to clean the terminal with contact cleaning solution and file it slowly with fine paper sand, yet smurf or garble was still there. I think its more on the power sequence and firmware issues.
My recent Katana WOW!!!!
Some thoughts about the Katana and power supplies...
I believe Allo has done a great job developing a high-quality DIY DAC designed to fit on a Raspberry Pi. Of course, as a DIY DAC, the end-user needs to mate it with an RPi, appropriate power supplies for the RPi and the Katana, and put it in a case (if desired).
Most of those buying a Katana will want to use a limited number of fairly low cost supplies to power the RPi and Katana/Isolator stack... likely the minimum 2. Allo has also done a good job of making the Katana sound as good as possible in that configuration. AND that is pretty good.
BUT a lot of what distinguishes a $450 RPi / Katana / 2 low-cost power supplies DAC from a $1000 DAC from a $5,000 DAC from a $10,000 DAC are better and more sophisticated power supplies and a fancier case. That's not all... better and more input interfaces, better output stages, alternative filtering, or non-traditional non-DAC-chip setups also drive the price and quality up. We can't deal with these latter items without re-engineering the Katana. AND regarding the case, if you don't like the ones available from Allo and others that will fit, you're on your own. But of course, it IS a DIY DAC, right?
BUT we can buy and/or DIY power supplies. AND that's where a significant increase in sound quality is available.
In an earlier post, I'd suggested a recent set of related reviews posted on Computer Audiophile. Part of it was to refute the oft-repeated comment "Doesn't the DAC chip chosen determine a unit's SQ?". Quick tip... it doesn't! The review articles are:
Intro: My Quest for a New DAC - Introduction to the Series
Mytek Brooklyn DAC: My Quest for a New DAC Part 1 - The Mytek Brooklyn DAC+ with Uptone JS-2 Power Supply
Ayre QX-8 DAC: My Quest for a new DAC, Part 2 - Ayre QX-8
Denafrips Terminator DAC: My Quest for a New DAC, Part 3 - Denafrips Terminator
iFi DSD Pro DAC: My Quest for a New DAC, Part 4 - iFi Pro iDSD (and friends)
One key point of interest in these reviews are the comparisons between the Ayre Codex ($1,800) and QX-8 ($5,500), and QX-5 ($10,000). The Codex uses the previous generation ES9018K2M DAC chip, the QX-8 uses the same ES9038Q2M as the Katana. AND the QX-5 the ES9028PRO. BUT the biggest differences between those units (as outlined in the review) are more sophisticated and expensive power supplies as you go up in price and quality.
Another key point of interest is that several of the DACs (Mytek Brooklyn, iFi Pro iDSD) use external power supplies and the reviewer also tests them with higher quality supplies, finding significant SQ increases with more expensive and sophisticated supplies.
AND another key point is that the Ayre QX-8, using the same DAC chip as the Katana, beats the Mytek, base iFi Pro iDSD, and Schit Yggdrasil, roughly equals the Denafrips, and is not far behind the nearly $10,000 USD Ayre QX-5. THAT says a lot about how much EVERYTHING beyond the DAC chip contributes to the SQ of a DAC. AND about how good a DAC using the ES9038Q2M can be.
Can you make a Katana equal the SQ of the QX-8? I doubt it. Ayre has included a number of additional features in the QX-8 that aren't or can't easily be included on the Katana. BUT I suspect the best power supplies will take it a good bit of the way there!
I suggest you think of the Katana as a component in a DIY DAC system that can be anywhere from good to VERY GOOD depending on how you power it.
I say this after an experience this week, where I was testing one of the levels of power supplies I will be comparing for a final review on the Katana. The SQ with these supplies, after break-in, produced the best sound I'd gotten from the Katana so far AND beat what I had expected to be the best sounding set of supplies.
These supplies were as follows:
- RPi <- K&K 12 watt Low Voltage power supply modified with somewhat larger United Chemi-Con KYB series caps (I don't like the sound of the Panasonic caps they use) and a DIY C-L-C AC filter
- Katana DAC board <- 1/2 Stammheim 5V 3||LT3045 regulator board <- 13V raw DC from 47,000/16V Jensen 4-pole cap, 4 DSEP30-6A diodes as a full-wave bridge, 1 secondary of a Hammond 229D16 transformer and a DIY C-L-C AC filter
- Katana Microprocessor board <- both halves of an OPC 5V 3||LT3042 regulator board paralleled on the output and 2 separate raw DC supplies, one into each half, same supply as above, but each secondary of the transformer producing a raw DC supply... note that while the OPC board is no longer available, the equivalent Stammheim board will work as well or better
- Katana Output stage <- +-15V Sparkos Labs regulators <- +-23V raw DC from 2 47,000/25V 4-pole caps, 4 DSEP30-6A as a full-wave bridge, 1 65VA Chinese R-Core transformer with 2 15V/2.1A secondaries
The sound I got from this setup was VERY dynamic, expressive, with great pacing and PRAT. The overall directness, clarity and excitement of vocals, and great dynamic jump I'd attribute to the Sparkos Lab based Class-A output stages, which shined in this setup! I thought I had already heard the Katana at its best, which was VERY GOOD. I was seriously wrong!
The sound was in many aspects at the same level as the best SQ I get from my systems with much more expensive DIY DACs, used with the same (or similar) supplies.
I'll say more about power supplies and some aspects of my setups that help produce this level of SQ in some later posts. BUT after listening several nights to this setup, I just had to share my findings and excitement!
Greg in Mississippi
P.S. This was not intended as a 'how-to-duplicate-this' article, though experienced DIY'ers could do so. BUT to share my experience that while Allo has done a great job making a DIY DAC that works well with budget supplies, better supplies can take it so much farther. This is NOT a patch on what Allo has done. Again, read the DAC reviews and see that at least in the Ayre line of DACs, a lot of the difference between a $2000, a $5000, and at $10,000 DAC is the power supplies.
Some thoughts about the Katana and power supplies...
I believe Allo has done a great job developing a high-quality DIY DAC designed to fit on a Raspberry Pi. Of course, as a DIY DAC, the end-user needs to mate it with an RPi, appropriate power supplies for the RPi and the Katana, and put it in a case (if desired).
Most of those buying a Katana will want to use a limited number of fairly low cost supplies to power the RPi and Katana/Isolator stack... likely the minimum 2. Allo has also done a good job of making the Katana sound as good as possible in that configuration. AND that is pretty good.
BUT a lot of what distinguishes a $450 RPi / Katana / 2 low-cost power supplies DAC from a $1000 DAC from a $5,000 DAC from a $10,000 DAC are better and more sophisticated power supplies and a fancier case. That's not all... better and more input interfaces, better output stages, alternative filtering, or non-traditional non-DAC-chip setups also drive the price and quality up. We can't deal with these latter items without re-engineering the Katana. AND regarding the case, if you don't like the ones available from Allo and others that will fit, you're on your own. But of course, it IS a DIY DAC, right?
BUT we can buy and/or DIY power supplies. AND that's where a significant increase in sound quality is available.
In an earlier post, I'd suggested a recent set of related reviews posted on Computer Audiophile. Part of it was to refute the oft-repeated comment "Doesn't the DAC chip chosen determine a unit's SQ?". Quick tip... it doesn't! The review articles are:
Intro: My Quest for a New DAC - Introduction to the Series
Mytek Brooklyn DAC: My Quest for a New DAC Part 1 - The Mytek Brooklyn DAC+ with Uptone JS-2 Power Supply
Ayre QX-8 DAC: My Quest for a new DAC, Part 2 - Ayre QX-8
Denafrips Terminator DAC: My Quest for a New DAC, Part 3 - Denafrips Terminator
iFi DSD Pro DAC: My Quest for a New DAC, Part 4 - iFi Pro iDSD (and friends)
One key point of interest in these reviews are the comparisons between the Ayre Codex ($1,800) and QX-8 ($5,500), and QX-5 ($10,000). The Codex uses the previous generation ES9018K2M DAC chip, the QX-8 uses the same ES9038Q2M as the Katana. AND the QX-5 the ES9028PRO. BUT the biggest differences between those units (as outlined in the review) are more sophisticated and expensive power supplies as you go up in price and quality.
Another key point of interest is that several of the DACs (Mytek Brooklyn, iFi Pro iDSD) use external power supplies and the reviewer also tests them with higher quality supplies, finding significant SQ increases with more expensive and sophisticated supplies.
AND another key point is that the Ayre QX-8, using the same DAC chip as the Katana, beats the Mytek, base iFi Pro iDSD, and Schit Yggdrasil, roughly equals the Denafrips, and is not far behind the nearly $10,000 USD Ayre QX-5. THAT says a lot about how much EVERYTHING beyond the DAC chip contributes to the SQ of a DAC. AND about how good a DAC using the ES9038Q2M can be.
Can you make a Katana equal the SQ of the QX-8? I doubt it. Ayre has included a number of additional features in the QX-8 that aren't or can't easily be included on the Katana. BUT I suspect the best power supplies will take it a good bit of the way there!
I suggest you think of the Katana as a component in a DIY DAC system that can be anywhere from good to VERY GOOD depending on how you power it.
I say this after an experience this week, where I was testing one of the levels of power supplies I will be comparing for a final review on the Katana. The SQ with these supplies, after break-in, produced the best sound I'd gotten from the Katana so far AND beat what I had expected to be the best sounding set of supplies.
These supplies were as follows:
- RPi <- K&K 12 watt Low Voltage power supply modified with somewhat larger United Chemi-Con KYB series caps (I don't like the sound of the Panasonic caps they use) and a DIY C-L-C AC filter
- Katana DAC board <- 1/2 Stammheim 5V 3||LT3045 regulator board <- 13V raw DC from 47,000/16V Jensen 4-pole cap, 4 DSEP30-6A diodes as a full-wave bridge, 1 secondary of a Hammond 229D16 transformer and a DIY C-L-C AC filter
- Katana Microprocessor board <- both halves of an OPC 5V 3||LT3042 regulator board paralleled on the output and 2 separate raw DC supplies, one into each half, same supply as above, but each secondary of the transformer producing a raw DC supply... note that while the OPC board is no longer available, the equivalent Stammheim board will work as well or better
- Katana Output stage <- +-15V Sparkos Labs regulators <- +-23V raw DC from 2 47,000/25V 4-pole caps, 4 DSEP30-6A as a full-wave bridge, 1 65VA Chinese R-Core transformer with 2 15V/2.1A secondaries
The sound I got from this setup was VERY dynamic, expressive, with great pacing and PRAT. The overall directness, clarity and excitement of vocals, and great dynamic jump I'd attribute to the Sparkos Lab based Class-A output stages, which shined in this setup! I thought I had already heard the Katana at its best, which was VERY GOOD. I was seriously wrong!
The sound was in many aspects at the same level as the best SQ I get from my systems with much more expensive DIY DACs, used with the same (or similar) supplies.
I'll say more about power supplies and some aspects of my setups that help produce this level of SQ in some later posts. BUT after listening several nights to this setup, I just had to share my findings and excitement!
Greg in Mississippi
P.S. This was not intended as a 'how-to-duplicate-this' article, though experienced DIY'ers could do so. BUT to share my experience that while Allo has done a great job making a DIY DAC that works well with budget supplies, better supplies can take it so much farther. This is NOT a patch on what Allo has done. Again, read the DAC reviews and see that at least in the Ayre line of DACs, a lot of the difference between a $2000, a $5000, and at $10,000 DAC is the power supplies.
Last edited:
SMPS versus Linear Supplies
I know some have had some good results with Switched Mode Power Supplies. AND I have too, though mostly with amplifiers powered by SMPSs. BUT my experiences generally put average-to-good linear supplies above the same rough-quality SMPSs. Some SMPS experiences (mine and others):
- I compared the iFi 5V to the modified K&K Low Voltage supply (described in a previous post) powering both RPis and my SDTrans384 SD card player. Interesting that on short listen, I ccouldn't hear much of a difference between them... but on extended listening the SQ with the K&K just sounded more like music and was more engaging.
- I lent my iFi 5V to a friend along with some modified Jameco 5V/1A linear wallwarts. His impressions were about the same as mine above. (AND YES, someday I'll do a quick how-to on the Jameco mods).
- I used the supplied SMPS when I first started running Uptone Audio LPS-1 Ultracap supplies. In my upstairs system, while I could not hear a difference in the SQ between that supply and an appropriate linear one, I DID get some buzzing through my S&B TX102 transformer volume control using the SMPS.
- In the articles I linked in a previous post, the iFi iDSD Pro was first tested with the supplied iFi SMPS, then with an Uptone Audio JS-2 and a Paul Hynes SR-7. Both were judged to be better.
- I also have an iFi Phono 2, which has gotten good reviews and which I think sounds pretty good. There are comments on the Audiogon forums where one poster says he gets a significant improvement with a good linear supply.
OTOH, there are a number of highly regarded high-end manufacturers using SMPSs besides iFi... Linn and Emperical Audio quickly come to mind, but there are many others, along with David Berning who has been using SMPSs to good effect in his well-regarded tube gear since the late 1980s! AND a growing number of amplifiers use SMPSs, including ones based on the Class D B&O Icepower and the various Hypex power supplies and modules. AND I have used both to good effect, although my current main amplifiers (PS Audio BHK 250s) DO have linear supplies.
Why do some like SMPSs & others not? At one level, I am sure much can be attributed to system differences along with listening preferences and person-to-person hearing differences.
I think another factor may be a persons's AC environment. In my case, I have done a lot around our home to reduce AC line noise into my audio gear:
- Replacing flourescent lights with halogens, sticking with incandesent bulbs instead of going to CFLs or LEDs.
- Adding clamp-on AC filter chokes on all potentially noisy equipment AC lines and other parallel AC filters on those lines and on the same lines as the audio gear. AND unplugging known noisy SMPS-powered equipment when not in use.
- Reducing the number of SMPSs in the house. EVEN my phone chargers use Jameco 5V linear supplies!
- Using DIY'd linear supplies for all of my audio-associated networking gear and computer gear, with each including a DIY'd C-L-C AC filter to reduce equipment noise feeding into the AC lines.
- Using a PS Audio P15 power regenerator in each of my 2 systems to provide clean AC for the 'audio' gear.
- Using off-the-grid supplies (such as Uptone Audio Ultracap supplies) where they make sense and provide audible benefits.
- Using an AC noise meter to provide some level of confirmation that my DIY'd supplies don't feed much noise back into the AC lines. For example, I built some linear supplies to power my Uptone Audio Ultracap supplies. After checking them with the AC noise meter, I made some mods to them that took them from making the AC line noisier to actually reducing noise on the AC line.
I suspect in my likely quieter than normal AC power environment, any noise transmitted back into the AC line or into the powered audio or audio-related gear MAY be more audible than in a setup with less heroic measures.
Still, SMPSs are here to stay and I am hopeful that as they are further developed they will get better and better. For example, I have a lot of hope for the goodness of the in-development Allo Nirvana, based on what they've done with their other products in the past including the Katana. Once they are available, I will be comparing them against my DIY'd linears for powering the Katana, likely along with Allo's current low-cost SMPS supply.
So while I am hopeful that SMPSs can someday produce the same SQ I'm hearing with linear and off-the-grid supplies, IN MY EXPERIENCE testing the Katana in my systems AND to my ears, the best results I've gotten so far have been with fairly high-test linear supplies.
Greg in Mississippi
P.S. I wanted to post this today after my post above BECAUSE I have 1 theory as to why the setup I described sounded so good with the Katana AND why it beat my previous best off-the-grid setup. I think a lot of that has to do with the PS Audio P15s, which are definite upgrades over the P10s they replaced. ALL of the comparisions I'd done in the past between my DIY'd linear setups versus my off-the-grid setps were using the P10s. This was the first time I did that comparison after getting the P15s... and now realize I need to go back and re-do a number of my previous comparisons for a possible new benchmark.
I know some have had some good results with Switched Mode Power Supplies. AND I have too, though mostly with amplifiers powered by SMPSs. BUT my experiences generally put average-to-good linear supplies above the same rough-quality SMPSs. Some SMPS experiences (mine and others):
- I compared the iFi 5V to the modified K&K Low Voltage supply (described in a previous post) powering both RPis and my SDTrans384 SD card player. Interesting that on short listen, I ccouldn't hear much of a difference between them... but on extended listening the SQ with the K&K just sounded more like music and was more engaging.
- I lent my iFi 5V to a friend along with some modified Jameco 5V/1A linear wallwarts. His impressions were about the same as mine above. (AND YES, someday I'll do a quick how-to on the Jameco mods).
- I used the supplied SMPS when I first started running Uptone Audio LPS-1 Ultracap supplies. In my upstairs system, while I could not hear a difference in the SQ between that supply and an appropriate linear one, I DID get some buzzing through my S&B TX102 transformer volume control using the SMPS.
- In the articles I linked in a previous post, the iFi iDSD Pro was first tested with the supplied iFi SMPS, then with an Uptone Audio JS-2 and a Paul Hynes SR-7. Both were judged to be better.
- I also have an iFi Phono 2, which has gotten good reviews and which I think sounds pretty good. There are comments on the Audiogon forums where one poster says he gets a significant improvement with a good linear supply.
OTOH, there are a number of highly regarded high-end manufacturers using SMPSs besides iFi... Linn and Emperical Audio quickly come to mind, but there are many others, along with David Berning who has been using SMPSs to good effect in his well-regarded tube gear since the late 1980s! AND a growing number of amplifiers use SMPSs, including ones based on the Class D B&O Icepower and the various Hypex power supplies and modules. AND I have used both to good effect, although my current main amplifiers (PS Audio BHK 250s) DO have linear supplies.
Why do some like SMPSs & others not? At one level, I am sure much can be attributed to system differences along with listening preferences and person-to-person hearing differences.
I think another factor may be a persons's AC environment. In my case, I have done a lot around our home to reduce AC line noise into my audio gear:
- Replacing flourescent lights with halogens, sticking with incandesent bulbs instead of going to CFLs or LEDs.
- Adding clamp-on AC filter chokes on all potentially noisy equipment AC lines and other parallel AC filters on those lines and on the same lines as the audio gear. AND unplugging known noisy SMPS-powered equipment when not in use.
- Reducing the number of SMPSs in the house. EVEN my phone chargers use Jameco 5V linear supplies!
- Using DIY'd linear supplies for all of my audio-associated networking gear and computer gear, with each including a DIY'd C-L-C AC filter to reduce equipment noise feeding into the AC lines.
- Using a PS Audio P15 power regenerator in each of my 2 systems to provide clean AC for the 'audio' gear.
- Using off-the-grid supplies (such as Uptone Audio Ultracap supplies) where they make sense and provide audible benefits.
- Using an AC noise meter to provide some level of confirmation that my DIY'd supplies don't feed much noise back into the AC lines. For example, I built some linear supplies to power my Uptone Audio Ultracap supplies. After checking them with the AC noise meter, I made some mods to them that took them from making the AC line noisier to actually reducing noise on the AC line.
I suspect in my likely quieter than normal AC power environment, any noise transmitted back into the AC line or into the powered audio or audio-related gear MAY be more audible than in a setup with less heroic measures.
Still, SMPSs are here to stay and I am hopeful that as they are further developed they will get better and better. For example, I have a lot of hope for the goodness of the in-development Allo Nirvana, based on what they've done with their other products in the past including the Katana. Once they are available, I will be comparing them against my DIY'd linears for powering the Katana, likely along with Allo's current low-cost SMPS supply.
So while I am hopeful that SMPSs can someday produce the same SQ I'm hearing with linear and off-the-grid supplies, IN MY EXPERIENCE testing the Katana in my systems AND to my ears, the best results I've gotten so far have been with fairly high-test linear supplies.
Greg in Mississippi
P.S. I wanted to post this today after my post above BECAUSE I have 1 theory as to why the setup I described sounded so good with the Katana AND why it beat my previous best off-the-grid setup. I think a lot of that has to do with the PS Audio P15s, which are definite upgrades over the P10s they replaced. ALL of the comparisions I'd done in the past between my DIY'd linear setups versus my off-the-grid setps were using the P10s. This was the first time I did that comparison after getting the P15s... and now realize I need to go back and re-do a number of my previous comparisons for a possible new benchmark.
@jonners,
Yes. I actually only have Katanas with that style output stage here, I'll update once I get a production unit with both. I DID compare earlier with / without the Rasmussen filter, but at the end I was comparing various versions of that configuration.
I should add that I also have not tried any Katana on a linear-regulator-modified RPi using LDOVR.com's RPi Mezzanine board. Those are currently my reference RPi sources and I expect a further SQ lift with them.
Greg in Mississippi
Yes. I actually only have Katanas with that style output stage here, I'll update once I get a production unit with both. I DID compare earlier with / without the Rasmussen filter, but at the end I was comparing various versions of that configuration.
I should add that I also have not tried any Katana on a linear-regulator-modified RPi using LDOVR.com's RPi Mezzanine board. Those are currently my reference RPi sources and I expect a further SQ lift with them.
Greg in Mississippi
Last edited:
Hi Greg,
A question for you, if I may: Katana sells for $250 last I checked (w/o RPi). I'm wondering what the full cost would be including power supplies, isolator, transformers, RPi, maybe a case, etc., for a Katana with the best sound quality possible. Would it end up being a $500 dac, or maybe a $700 dac? What do you think?
A question for you, if I may: Katana sells for $250 last I checked (w/o RPi). I'm wondering what the full cost would be including power supplies, isolator, transformers, RPi, maybe a case, etc., for a Katana with the best sound quality possible. Would it end up being a $500 dac, or maybe a $700 dac? What do you think?
@Greg
I read your recent posts. Yep. I did. I always do. I guess it took you hours.
To be honest.
You're writing up all kind of (weird) stuff. Then you compare apples and oranges.
And then you describe the greatest solution ever - and after all that Markw4 wants
a pricetag on that. I was asking myself if I missed the joke here.
IMO your stuff confuses more then it helps.
I am also a tweaker by heart. Why don't I feel tempted to follow any of your stuff!?!?
Sometimes I get the feeling you'll loose yourself in the 50 ongoing projects and hundreds of tweaks you try every other day on all of them.
Please, don't take it personal. You do contribute valuable stuff to the crowd (once in a while)
I'd really appreciate, if you try to put yourself in our shoes, and just outline a nice and simple solution that can be accomplished by most of us.
Thx. Always nice talking to you.
PS:
One more comment/advise:
If you compare a stock iFi iPower to a "tweaked/modified" linear supply and conclude with a slight preference for that tweaked linear supply.
Why don't you just tweak the iFi a little!?!? Just cut the cable down to 10inches, it's much too long, get rid of the awful plugs and connectors, and then attach a buffer cap.
Quite some people also seem to enjoy that DCminus2ACearth tweak - you can even try that one. I'm just saying. Enjoy.
I read your recent posts. Yep. I did. I always do. I guess it took you hours.
To be honest.
You're writing up all kind of (weird) stuff. Then you compare apples and oranges.
And then you describe the greatest solution ever - and after all that Markw4 wants
a pricetag on that. I was asking myself if I missed the joke here.
IMO your stuff confuses more then it helps.
I am also a tweaker by heart. Why don't I feel tempted to follow any of your stuff!?!?
Sometimes I get the feeling you'll loose yourself in the 50 ongoing projects and hundreds of tweaks you try every other day on all of them.
Please, don't take it personal. You do contribute valuable stuff to the crowd (once in a while)
I'd really appreciate, if you try to put yourself in our shoes, and just outline a nice and simple solution that can be accomplished by most of us.
Thx. Always nice talking to you.
PS:
One more comment/advise:
If you compare a stock iFi iPower to a "tweaked/modified" linear supply and conclude with a slight preference for that tweaked linear supply.
Why don't you just tweak the iFi a little!?!? Just cut the cable down to 10inches, it's much too long, get rid of the awful plugs and connectors, and then attach a buffer cap.
Quite some people also seem to enjoy that DCminus2ACearth tweak - you can even try that one. I'm just saying. Enjoy.
HI Greg
We are also doing some more experiments.. trying to move those 47000 caps after the LDOs maybe ? (same place as 1000uF)
Behind the scenes we are working on the PSUs.
Nirvana SMPS. I think everyone here knows about it. 1 output
2. LPS with dual output (3A and 1A) Ultra low noise.
We are facing significant difficulties to solve all bugs and every day we are testing and measuring. We are confident to bring both to the market.
I had a quick exchange with Ioan at Allo wondering if creating a separate thread to focus on getting the best out of the Katana is better than cluttering this thread with a lot of our ideas and questions/answers. They said 'yes' so I've started on over in the 'PC Based' forum where we can not only discuss power options, but also RPi HW/SW tweaks and other ideas for getting the Katana to sound its best.
I'll work with Allo and the moderators to see if we can get some of the relevent posts moved from this thread into the new one.
AND I'm very interested to see/hear what they will come up for better power solutions for the Katana and their other units, which all seem to do pretty well with lower-cost power supplies, but IMHO also reflect the benefits of the best power one can use.
In the meantime, some quick answers to some of the questions above:
@drgnanam, sorry, I don't have either the equipment or the expertise to do the measurements you suggested. Hopefully some one will be able to provide some assistance on this.
@Markw4, I'll post my quick tally on the total cost of an RPi / isolator / Katana combo using the power supplies I mentioned in the new thread later tonight or tomorrow.
@Soundcheck, I'm very glad you read posts. AND thanks for the tips on the iFi iPower. I had shortened the cable, replaced the output connector with a good high-current one, and had added a buffer cap on the RPis used after your very early recommendations.
So see, I read your posts too.
Also, I had done the comparison BEFORE the recommendation from John Swenson to ground the negative side of the output of any SMPSs to shunt away the high-impedance leakage current. BUT I do find grounding my RPis to be beneficial (especially with an isolator), if only to make sure there is not a high ground potential between the RPi and upstream / downstream gear. Not sure if grounding the RPi is as good as grounding the SMPS output, but the system was grounded.
I must admit I remain puzzled why you continue to feel the need to used demeaning and diminishing comments when responding to or referring to me...
"I guess it took you hours."
"You're writing up all kind of (weird) stuff. Then you compare apples and oranges."
"IMO your stuff confuses more then it helps."
"You do contribute valuable stuff to the crowd (once in a while)"
I come away from your posts about me as someone who is threatened by what I say. Surely I can post my experiences and suggestions without you needing to put me down. Maybe just ask questions? I'll answer just like anyone else.
You did a tiny bit better (no name calling). Still, do better!
Greg in Mississippi
I'll work with Allo and the moderators to see if we can get some of the relevent posts moved from this thread into the new one.
AND I'm very interested to see/hear what they will come up for better power solutions for the Katana and their other units, which all seem to do pretty well with lower-cost power supplies, but IMHO also reflect the benefits of the best power one can use.
In the meantime, some quick answers to some of the questions above:
@drgnanam, sorry, I don't have either the equipment or the expertise to do the measurements you suggested. Hopefully some one will be able to provide some assistance on this.
@Markw4, I'll post my quick tally on the total cost of an RPi / isolator / Katana combo using the power supplies I mentioned in the new thread later tonight or tomorrow.
@Soundcheck, I'm very glad you read posts. AND thanks for the tips on the iFi iPower. I had shortened the cable, replaced the output connector with a good high-current one, and had added a buffer cap on the RPis used after your very early recommendations.
So see, I read your posts too.
Also, I had done the comparison BEFORE the recommendation from John Swenson to ground the negative side of the output of any SMPSs to shunt away the high-impedance leakage current. BUT I do find grounding my RPis to be beneficial (especially with an isolator), if only to make sure there is not a high ground potential between the RPi and upstream / downstream gear. Not sure if grounding the RPi is as good as grounding the SMPS output, but the system was grounded.
I must admit I remain puzzled why you continue to feel the need to used demeaning and diminishing comments when responding to or referring to me...
"I guess it took you hours."
"You're writing up all kind of (weird) stuff. Then you compare apples and oranges."
"IMO your stuff confuses more then it helps."
"You do contribute valuable stuff to the crowd (once in a while)"
I come away from your posts about me as someone who is threatened by what I say. Surely I can post my experiences and suggestions without you needing to put me down. Maybe just ask questions? I'll answer just like anyone else.
You did a tiny bit better (no name calling). Still, do better!
Greg in Mississippi
Threatened !?!?
Nope. Just disappointed. Because I think/thought you can do better then that.
I just remind you at the Katana listening experience of -1db at 20kHz you reported the other day.
Somebody called you out on that one. And you simply laughed it away. That didn't help your credibility.
As I said, get a little more focused and be a bit more precise, instead of spreading all kind of stuff.
If you talk about "iFi iPower" vs modified linear supply, which then turns out to be a "modified iFi iPower" vs. "a modified linear PS" things become a little clearer.
Obviously you didn't mention what mods you applied.
How do you think anybody over here - and this is DIY-A and not CA - can replicate what you're doing?? That's what your texts and findings is making pretty much useless.
Again. All this is nothing personal! I actually think you're a great fellow.
And if anybody else gives "feedback" or writes "reviews" without clearly stating the HW environment , OS, SW setup and settings I consider these pretty useless as well.
Allo has a different view on that of course. Any feedback is better then none.
That'll be it. No further NON-Katana related stuff from my side.
Enjoy.
On this regard,
Can you be more detailed on how you make these devices intrinsically safe? Im just curious on the SMPS i bought from Allo! I have 5 of them. Im worried because after watching the review of John Darko on the Allo signature (the battery pack smoked twice). I don't know whether John was reckless or he was too excited to connect the power pack. It appears to me that the battery pack or any other power supply, Allo offers, are not intrinsically safe.
Not knowing why someone who can't hear 20kHz might hear what is described as -1dB @20kHz should not necessarily hurt credibility, seems to me. It may be quite possible to hear the effects at much lower frequencies, although one not versed in arts, a non-engineer, might not know why.
I would agree, however, that anyone who does not have Greg's exact setup and power supplies might be hard put to imagine what something sounds like. Unfortunately, there is no good way to describe to someone an experience they have never had. One can try, and I think Greg tries, but, for example, there is no way to know what exactly yellow is if you have never seen yellow. You could say that if you mix green and blue light then you get yellow, but that might not help much. With such difficulties possible, I would rather that Greg not be dissuaded from further posting by excessive criticism, even if I know I will have to wait to find out what Katana 1.2 actually sounds like until there is one in my listening room.
A little off topic, but I thought you might be interested in this video Darko made on the Allo Digione Signiture.
https://darko.audio/2018/11/a-short-film-about-the-allo-digione-signature/
https://darko.audio/2018/11/a-short-film-about-the-allo-digione-signature/
Markw4 and Soundcheck, thanks for useful replies.
Mark, thanks for understanding that I did not say I could hear a roughly 1db drop at 20K (maybe when I was 20 years old, but I'm better than 3x that old now), but that I could hear a difference in the sound that I believed was related to that drop. Others had reported differences between the 2 output stages, so I don't feel I am out in left field on this.
And Mark, I'm not dissuaded.
Soundcheck, I appreciate you dialing back the derogatory comments and name calling. I am not bothered by questions and criticisms. I won't put up with name-calling and put-downs.
I understand what I write doesn't fit with what you want to hear. Ok. I'm not trying to write what you want to hear. I'm explaining what I hear, what I do, and how I understand it in terms that make sense to me... and I assume some others. For example, my description of my power supplies would make good sense to a moderately-experienced DIY'er who has done several scratch builds where they figured out how the components worked based on some electrical knowledge and the relevant schematics and adapted them to their needs. I believe someone with that level of knowledge could duplicate them from my descriptions pretty easily. I'm not trying to get into a sufficient level of detail that someone with no DIY experience could use to duplicate my supplies. That is a level of explanation I don't have time for right now. I DO appreciate things like your blog posts where you go into a good level of detail on how to duplicate some of your findings... given one has an appropriate level of computer and Linux knowledge. I'm happy to have a barely adequate understanding of most of what you share. BUT often I have to dig for more and I'm ok with that as my knowledge level grows. I appreciate that you challenge me to do that.
On a couple of other things... first, my not going into details about replacing the iFi iPower stock plug with one that mates and using it on an RPi that already had local filter cap added didn't change the results of my comparision between the K&K & iFi supplies. Yes, the iFi was working a little better than a stock one in that setup. OTOH, the modified K&K mated via the same style plug and into the same RPi with the filter cap. I'm not getting what your deal with that is.
Also, in a previous post, you commented "Sometimes I get the feeling you'll loose yourself in the 50 ongoing projects and hundreds of tweaks you try every other day on all of them." That is drawing a conclusion about what I have and am doing that you don't have any basis to make. For example, in the case of the AC power improvement efforts I outlined, they've all been part of my audio setups for a number of years, all over 5 years and some for almost 10 years. Yes I upgraded my PS Audio AC regenerator to a newer model earlier this summer, but while it was a good SQ improvement, it did not change the basic character of my setups. Stick to commenting on things you have direct experience with and I will too.
Back to the Katana... I played music via the Katana today while I was upstairs doing some other tasks. I was struck again with how good it is sounding and quickly sat down to add more recordings to the current playlist. I quickly forgot about my reason for being there as I just enjoyed the music and great sound. Things that stuck out to me tonight were the sense of rhythmic drive and pacing, dynamics, vocal clarity, and how it conveyed a good sense of the music and musical experience. It really did sound very good to me in my setup.
Markw4, you had asked what it would cost to duplicate my Katana setup. I did a quick tabulation and am posting that at the other thread I started here:
https://www.diyaudio.com/forums/pc-based/329911-getting-allo-coms-katana-dac.html#post5600146
No, it is not inexpensive. I was actually surprised at how much $ I have into that setup (and that is counting JUST the minimum amount to duplicate what is needed to run the Katana, not the rest of the supplies I have to cover all of my digital sources!).
Note that the other digital sources I compared to the Katana were more expensive and while they shared many of the same power supply components that I used with the Katana, they often needed additional and often more expensive power supplies. That the Katana provides a similar level of performance as my more expensive DIY DACs such as the Twisted Pear and Soekris units with more expensive power setups says a lot for how good it is with really good power.
More details in that thread.
Greg in Mississippi
Mark, thanks for understanding that I did not say I could hear a roughly 1db drop at 20K (maybe when I was 20 years old, but I'm better than 3x that old now), but that I could hear a difference in the sound that I believed was related to that drop. Others had reported differences between the 2 output stages, so I don't feel I am out in left field on this.
And Mark, I'm not dissuaded.
Soundcheck, I appreciate you dialing back the derogatory comments and name calling. I am not bothered by questions and criticisms. I won't put up with name-calling and put-downs.
I understand what I write doesn't fit with what you want to hear. Ok. I'm not trying to write what you want to hear. I'm explaining what I hear, what I do, and how I understand it in terms that make sense to me... and I assume some others. For example, my description of my power supplies would make good sense to a moderately-experienced DIY'er who has done several scratch builds where they figured out how the components worked based on some electrical knowledge and the relevant schematics and adapted them to their needs. I believe someone with that level of knowledge could duplicate them from my descriptions pretty easily. I'm not trying to get into a sufficient level of detail that someone with no DIY experience could use to duplicate my supplies. That is a level of explanation I don't have time for right now. I DO appreciate things like your blog posts where you go into a good level of detail on how to duplicate some of your findings... given one has an appropriate level of computer and Linux knowledge. I'm happy to have a barely adequate understanding of most of what you share. BUT often I have to dig for more and I'm ok with that as my knowledge level grows. I appreciate that you challenge me to do that.
On a couple of other things... first, my not going into details about replacing the iFi iPower stock plug with one that mates and using it on an RPi that already had local filter cap added didn't change the results of my comparision between the K&K & iFi supplies. Yes, the iFi was working a little better than a stock one in that setup. OTOH, the modified K&K mated via the same style plug and into the same RPi with the filter cap. I'm not getting what your deal with that is.
Also, in a previous post, you commented "Sometimes I get the feeling you'll loose yourself in the 50 ongoing projects and hundreds of tweaks you try every other day on all of them." That is drawing a conclusion about what I have and am doing that you don't have any basis to make. For example, in the case of the AC power improvement efforts I outlined, they've all been part of my audio setups for a number of years, all over 5 years and some for almost 10 years. Yes I upgraded my PS Audio AC regenerator to a newer model earlier this summer, but while it was a good SQ improvement, it did not change the basic character of my setups. Stick to commenting on things you have direct experience with and I will too.
Back to the Katana... I played music via the Katana today while I was upstairs doing some other tasks. I was struck again with how good it is sounding and quickly sat down to add more recordings to the current playlist. I quickly forgot about my reason for being there as I just enjoyed the music and great sound. Things that stuck out to me tonight were the sense of rhythmic drive and pacing, dynamics, vocal clarity, and how it conveyed a good sense of the music and musical experience. It really did sound very good to me in my setup.
Markw4, you had asked what it would cost to duplicate my Katana setup. I did a quick tabulation and am posting that at the other thread I started here:
https://www.diyaudio.com/forums/pc-based/329911-getting-allo-coms-katana-dac.html#post5600146
No, it is not inexpensive. I was actually surprised at how much $ I have into that setup (and that is counting JUST the minimum amount to duplicate what is needed to run the Katana, not the rest of the supplies I have to cover all of my digital sources!).
Note that the other digital sources I compared to the Katana were more expensive and while they shared many of the same power supply components that I used with the Katana, they often needed additional and often more expensive power supplies. That the Katana provides a similar level of performance as my more expensive DIY DACs such as the Twisted Pear and Soekris units with more expensive power setups says a lot for how good it is with really good power.
More details in that thread.
Greg in Mississippi