Allo's new Katana DAC joins other recent offerings such as the ApplePi DAC, Markw4's experiments with other ES9038Q2M boards, Ian's prototype ESS-based DACs, Abraxalito's LingDAC, and others in raising the bar for RPi I2S DAC Hats. I was one of the lucky ones who given the opportunity to hear this DAC as Allo refined it into the well-performing product it is today. I listened to the Katana with high-performing power supplies and was rewarded with sound in many ways as good as any I've had at home.
I posted some of my experiences with power options for the Katana, isolator, and RPi over in Allo's main vendor thread here:
New FIFO buffer for RPI/SBCs
I'm creating this thread to discuss getting the best from the Katana, including, but not exclusively power options. I'm hopeful Soundcheck and others will post some of their op system, player software, driver, and hardware tweaks. And I'm sure there are other areas to explore.
Based on Allo's recommendations AND my experience, you'll get the best performance from your Katana with 4 power supplies:
- 5V/1A-2A RPi / Isolator input (>1.2A or may not boot consistently in my experience)
- 5V/200mA Isolator output / DAC board (measured 100mA DAC board only)
- 5V/20mA Microprocessor board (with +-15V DC-DC converter disabled, 1A with them active)
- +-15V/100mA-150mA / rail Opamp board
I am focusing on variations on this configuration in this thread.
I outlined the components and configuration of the best supply setup I found in my testing so far in post #4 below. (NOTE that the cost I listed for the RPi and Katana package combined is about $120USD high, due to misunderstanding how Allo listed the components). I will focus on additional options for this configuration in this thread and where I can make comparisons, how they compare to what has been my best so far.
Below are some sources for appropriate completed supplies and kits, and components that will work for the various Katana rails. This is not an exhaustive list, feel free to post or PM me with additional sources and I'll add them here. AND as you have tried them with your Katana, please post your results:
Mamboberry HD DAC+ - Collybia.com - 5V Mambo power supply
Twisted Pear Audio - 5V Placid HD or Centaur, +-15V Placid HD Bipolar or LCBPS, and appropriate transformers
www.ldovr.com - various DC input board sets for 5V & +-15V and DXP complete supplies for 5V
MPAudio | Home of the HPULN | LT3045 based Power Supplies - various DC and AC input board sets for 5V & +-15V and appropriate transformers
www.diyinhk.com - various DC and AC input board sets for 5V & +-15V and appropriate transformers
www.kandkaudio.com - 5V/12watt AC input low voltage power supply kit is what I use for RPi / Isolator input power and would also work well for the other 5V supplies
www.glassware.stores.yahoo.net - several AC and DC input power supply kits for 5V & +-15V.
www.amb.org - various DC and AC input regulator board sets and some parts... YOU will need to source transformers and the remaining parts
www.sparkoslabs.com - high-quality discrete regulators for building your own 5V & +-15V supplies
www.belleson.com - high-quality discrete regulators for building your own 5V & +-15V supplies & supply build articles
www.newclassd.com - high-quality discrete regulators for building your own 5V & +-15V supplies
www.diyaudio.com/forums/group-buys/322596-gb-salas-sslv1-3-ultra-bib.html - Salas shunt regulator boards and partial kits for 5V & +-15V... YOU will need to source transformers and the remaining parts... there are other products and group buys in the DIYAudio Vendor forums, please feel free to recommend additional products
www.jameco.com - low cost 5V/1A & 12V/1A linear regulated wall adapters that can be modified into credible low-cost alternative supplies for the Katana
One supply that has exhibited issues with the Katana is this one:
https://www.audiophonics.fr/fr/alim...re-regulee-op-tl072-mje15034-28v-p-12753.html
Based on several reports, these may require additional C on the output and possible connection to the load after they have fully powered up to function well on the Katana +-15V rails.
My tips on separating the Katana boards without breaking the inter-board connector pins in post 2574 of the main Allo.com thread
AND here's the current state of my Katana:
- 2nd release Katana with firmware fixing the original issue, but not the latest firmware
- Isolator 1.2
- Developmental upgrades that were incorporated in lastest production including additional power lines filtering, updated I/V filtering, and SQ mod (but using an alternative pre-I/V filter not chosen for production)
- +-15V supply (post #28)
- Direct 5V bypassing included connectors on DAC and Microprocessor boards (post #217)
- +-15V on-board LDO bypassing & revised filter Cs (posts #299, #301, #311, #316)
- DAC and Isolator board jumpers bypassed with soldered jumpers
Greg in Mississippi
I posted some of my experiences with power options for the Katana, isolator, and RPi over in Allo's main vendor thread here:
New FIFO buffer for RPI/SBCs
I'm creating this thread to discuss getting the best from the Katana, including, but not exclusively power options. I'm hopeful Soundcheck and others will post some of their op system, player software, driver, and hardware tweaks. And I'm sure there are other areas to explore.
Based on Allo's recommendations AND my experience, you'll get the best performance from your Katana with 4 power supplies:
- 5V/1A-2A RPi / Isolator input (>1.2A or may not boot consistently in my experience)
- 5V/200mA Isolator output / DAC board (measured 100mA DAC board only)
- 5V/20mA Microprocessor board (with +-15V DC-DC converter disabled, 1A with them active)
- +-15V/100mA-150mA / rail Opamp board
I am focusing on variations on this configuration in this thread.
I outlined the components and configuration of the best supply setup I found in my testing so far in post #4 below. (NOTE that the cost I listed for the RPi and Katana package combined is about $120USD high, due to misunderstanding how Allo listed the components). I will focus on additional options for this configuration in this thread and where I can make comparisons, how they compare to what has been my best so far.
Below are some sources for appropriate completed supplies and kits, and components that will work for the various Katana rails. This is not an exhaustive list, feel free to post or PM me with additional sources and I'll add them here. AND as you have tried them with your Katana, please post your results:
Mamboberry HD DAC+ - Collybia.com - 5V Mambo power supply
Twisted Pear Audio - 5V Placid HD or Centaur, +-15V Placid HD Bipolar or LCBPS, and appropriate transformers
www.ldovr.com - various DC input board sets for 5V & +-15V and DXP complete supplies for 5V
MPAudio | Home of the HPULN | LT3045 based Power Supplies - various DC and AC input board sets for 5V & +-15V and appropriate transformers
www.diyinhk.com - various DC and AC input board sets for 5V & +-15V and appropriate transformers
www.kandkaudio.com - 5V/12watt AC input low voltage power supply kit is what I use for RPi / Isolator input power and would also work well for the other 5V supplies
www.glassware.stores.yahoo.net - several AC and DC input power supply kits for 5V & +-15V.
www.amb.org - various DC and AC input regulator board sets and some parts... YOU will need to source transformers and the remaining parts
www.sparkoslabs.com - high-quality discrete regulators for building your own 5V & +-15V supplies
www.belleson.com - high-quality discrete regulators for building your own 5V & +-15V supplies & supply build articles
www.newclassd.com - high-quality discrete regulators for building your own 5V & +-15V supplies
www.diyaudio.com/forums/group-buys/322596-gb-salas-sslv1-3-ultra-bib.html - Salas shunt regulator boards and partial kits for 5V & +-15V... YOU will need to source transformers and the remaining parts... there are other products and group buys in the DIYAudio Vendor forums, please feel free to recommend additional products
www.jameco.com - low cost 5V/1A & 12V/1A linear regulated wall adapters that can be modified into credible low-cost alternative supplies for the Katana
One supply that has exhibited issues with the Katana is this one:
https://www.audiophonics.fr/fr/alim...re-regulee-op-tl072-mje15034-28v-p-12753.html
Based on several reports, these may require additional C on the output and possible connection to the load after they have fully powered up to function well on the Katana +-15V rails.
My tips on separating the Katana boards without breaking the inter-board connector pins in post 2574 of the main Allo.com thread
AND here's the current state of my Katana:
- 2nd release Katana with firmware fixing the original issue, but not the latest firmware
- Isolator 1.2
- Developmental upgrades that were incorporated in lastest production including additional power lines filtering, updated I/V filtering, and SQ mod (but using an alternative pre-I/V filter not chosen for production)
- +-15V supply (post #28)
- Direct 5V bypassing included connectors on DAC and Microprocessor boards (post #217)
- +-15V on-board LDO bypassing & revised filter Cs (posts #299, #301, #311, #316)
- DAC and Isolator board jumpers bypassed with soldered jumpers
Greg in Mississippi
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Markw4, you had asked what it would cost to duplicate my Katana setup in the main Allo.com thread. Here's my quick tabulation (forgive me if I made mistakes adding):
$43 - Raspberry Pi 2B
$429 - Base Katana... Katana for DietPi, isolator, extra output stage, 16GB SD card, black case (for isolator)
~$80 - RPi Power... K&K 5V/12W Low Voltage Power Supply kit ($52), parts for John Swenson transformer ringing snubber, upgrade caps / C-L-C AC filter / power cord (~$28)
~$227 - DAC & isolator boards power... MPAudio (Stammheim on DIYAudio) SD-HPULN PS ($102, NOTE you only use 1/2 of the supply), 47,000/16V Jensen 4-pole cap 47,000uF/16V ($53 PC), 4 DSEP30-06A diodes ($18 DK), Hammond 229D16 transformer ($29 DK), parts for John Swenson transformer ringing snubber / misc wiring/mounting hardware / AC filter cap / fused AC IEC socket / cap discharge resistor (~$25)
~$293 - DAC & isolator boards power... MPAudio (Stammheim on DIYAudio) SD-HPULN PS ($102), 2 47,000/16V Jensen 4-pole cap 47,000uF/16V ($106 PC), 8 DSEP30-06A diodes ($36 DK), Hammond 229D16 transformer ($29 DK), parts for 2 John Swenson transformer ringing snubbers / misc wiring/mounting hardware / cap discharge resistors (~$20) (note, shares the same AC IEC socket as above)
~$363 - Output Stage power... Sparkos Labs + and - regulators ($94), 2 47,000/25V Jensen 4-pole cap 47,000uF/25V ($136 PC), 4 DSEP30-06A diodes ($18 DK), 65W R-Core transformer ($75? EBay), input/output caps for the regulators / parts for 2 John Swenson transformer ringing snubbers / misc wiring/mounting hardware / fused AC IEC socket / cap discharge resistors (~$40)
$1436 (GULP!)
Note that this does not include shipping (significant for the R-Core transformers from China) taxes and custom fees, a case for the power supplies (mine is just mounted free-air on a bamboo cutting board), 3 AC cords (the ones I use are not expensive or fancy), and any additional connectors between the power supplies and the DAC (I use fairly expensive Hirose connectors that are now end-of-life), I suggest hardwire for best sound and low cost.
Also note I indicated suppliers in many cases... if not obvious in the description, I followed the cost with PC for PartsConnexion and DK for Digikey.
I understand most wouldn't want to spend this much for supplies for their Katana (or Boss or other RPi DAC) setup. You can still put together a VERY good high-quality power setup (that MIGHT end up being better than what I created for likely less $) using modules and components from Twisted Pear Audio, AMB, MPAudio, LDOVR.com and many others. The K&K Audio Low Voltage Supplies would also be a good bet not only for the RPi, but the DAC board and microprocessor board. Another direction would be to use supplies built using the Salas shunt regulators detailed here in DIYAudio and sold regularly in group buys (some would suggest these might be the best solution available... I would not argue with that, though I haven't tried them myself yet).
Another interesting option would be the C-L-C power supply John Swenson originally posted on the Audio Asylum that was the basis for the well-regarded Uptone AUdio JS-2 supply (see attached schematic & JS-2 picture). Based on what he wrote about it, you'd want to stick to the specified transformers, choke and raw DC caps, though I suspect you could use a different regulator and post-regulator cap without compromising performance. I'm not sure it if can source the current needed to power the output stage via the onboard DC-DC stages, but if you use a separate +-15V supply like I did, it should work very well too.
Any other options to add?
Greg in Mississippi
$43 - Raspberry Pi 2B
$429 - Base Katana... Katana for DietPi, isolator, extra output stage, 16GB SD card, black case (for isolator)
~$80 - RPi Power... K&K 5V/12W Low Voltage Power Supply kit ($52), parts for John Swenson transformer ringing snubber, upgrade caps / C-L-C AC filter / power cord (~$28)
~$227 - DAC & isolator boards power... MPAudio (Stammheim on DIYAudio) SD-HPULN PS ($102, NOTE you only use 1/2 of the supply), 47,000/16V Jensen 4-pole cap 47,000uF/16V ($53 PC), 4 DSEP30-06A diodes ($18 DK), Hammond 229D16 transformer ($29 DK), parts for John Swenson transformer ringing snubber / misc wiring/mounting hardware / AC filter cap / fused AC IEC socket / cap discharge resistor (~$25)
~$293 - DAC & isolator boards power... MPAudio (Stammheim on DIYAudio) SD-HPULN PS ($102), 2 47,000/16V Jensen 4-pole cap 47,000uF/16V ($106 PC), 8 DSEP30-06A diodes ($36 DK), Hammond 229D16 transformer ($29 DK), parts for 2 John Swenson transformer ringing snubbers / misc wiring/mounting hardware / cap discharge resistors (~$20) (note, shares the same AC IEC socket as above)
~$363 - Output Stage power... Sparkos Labs + and - regulators ($94), 2 47,000/25V Jensen 4-pole cap 47,000uF/25V ($136 PC), 4 DSEP30-06A diodes ($18 DK), 65W R-Core transformer ($75? EBay), input/output caps for the regulators / parts for 2 John Swenson transformer ringing snubbers / misc wiring/mounting hardware / fused AC IEC socket / cap discharge resistors (~$40)
$1436 (GULP!)
Note that this does not include shipping (significant for the R-Core transformers from China) taxes and custom fees, a case for the power supplies (mine is just mounted free-air on a bamboo cutting board), 3 AC cords (the ones I use are not expensive or fancy), and any additional connectors between the power supplies and the DAC (I use fairly expensive Hirose connectors that are now end-of-life), I suggest hardwire for best sound and low cost.
Also note I indicated suppliers in many cases... if not obvious in the description, I followed the cost with PC for PartsConnexion and DK for Digikey.
I understand most wouldn't want to spend this much for supplies for their Katana (or Boss or other RPi DAC) setup. You can still put together a VERY good high-quality power setup (that MIGHT end up being better than what I created for likely less $) using modules and components from Twisted Pear Audio, AMB, MPAudio, LDOVR.com and many others. The K&K Audio Low Voltage Supplies would also be a good bet not only for the RPi, but the DAC board and microprocessor board. Another direction would be to use supplies built using the Salas shunt regulators detailed here in DIYAudio and sold regularly in group buys (some would suggest these might be the best solution available... I would not argue with that, though I haven't tried them myself yet).
Another interesting option would be the C-L-C power supply John Swenson originally posted on the Audio Asylum that was the basis for the well-regarded Uptone AUdio JS-2 supply (see attached schematic & JS-2 picture). Based on what he wrote about it, you'd want to stick to the specified transformers, choke and raw DC caps, though I suspect you could use a different regulator and post-regulator cap without compromising performance. I'm not sure it if can source the current needed to power the output stage via the onboard DC-DC stages, but if you use a separate +-15V supply like I did, it should work very well too.
Any other options to add?
Greg in Mississippi
Attachments
Wow! That is very different to the simple idea that one can get a really good dac for $250 that rivals dacs costing $!,000 or more.
One can mod a cheap imported $39 dac (total cost maybe around $250 including power supplies) that may be very similar to Katana in terms of sound quality. Don't know yet, but that was the case for Katana 1.1, and the modded dacs have improved during the same time Katana was being improved. Unfortunately, it is a lot of work to do all the modding, and almost no one has the time and patience to do it all. However, $1,000 or so for one's labor might seem attractive to some.
As an existing Katana reviewer, I recently received an email saying that Katana 1.2 would be shipped to me soon in order to continue with the reviewing. As before, we are expecting to do listening comparisons between a highly modded $39 dac, Katana 1.2, and a Benchmark DAC-3. Should be interesting. We will be talking about it over in the 'ES9038Q2M board' thread.
One can mod a cheap imported $39 dac (total cost maybe around $250 including power supplies) that may be very similar to Katana in terms of sound quality. Don't know yet, but that was the case for Katana 1.1, and the modded dacs have improved during the same time Katana was being improved. Unfortunately, it is a lot of work to do all the modding, and almost no one has the time and patience to do it all. However, $1,000 or so for one's labor might seem attractive to some.
As an existing Katana reviewer, I recently received an email saying that Katana 1.2 would be shipped to me soon in order to continue with the reviewing. As before, we are expecting to do listening comparisons between a highly modded $39 dac, Katana 1.2, and a Benchmark DAC-3. Should be interesting. We will be talking about it over in the 'ES9038Q2M board' thread.
I do agree with Greg that good power is a key component to good sound, but I'm unlikely to invest an additional $1000 in power supplies.
To me, it becomes the somewhat standard issue with audio, dollars and diminishing returns. I tend to not go for that last 5-10% to save the dollars.
For +3.3V, I really like to use the A123 lifepo4 batteries, and would do the same here, with a simple linear PS to keep them charged. You can also use them for 5V, but you need two in series, becomes more complicated, and running the cells at 2.5V each is not optimal.
Ian is working with big super caps instead of lifepo4 and reported positive results, but I already have the batteries but may try the super caps in the future. I would expect super caps to be a better solution especially for 5V, but it will more expensive than lifepo4 batteries. Looking at prices, depends how low ESR you want, less than 1 milliohm will cost up to $75 each. The one Ian had in a picture is less, $20 each, and you need two for 5V of either.
For the +/-15, seems like a good reason to finally build some salas shunts I bought the parts for be never used.
Randy
To me, it becomes the somewhat standard issue with audio, dollars and diminishing returns. I tend to not go for that last 5-10% to save the dollars.
For +3.3V, I really like to use the A123 lifepo4 batteries, and would do the same here, with a simple linear PS to keep them charged. You can also use them for 5V, but you need two in series, becomes more complicated, and running the cells at 2.5V each is not optimal.
Ian is working with big super caps instead of lifepo4 and reported positive results, but I already have the batteries but may try the super caps in the future. I would expect super caps to be a better solution especially for 5V, but it will more expensive than lifepo4 batteries. Looking at prices, depends how low ESR you want, less than 1 milliohm will cost up to $75 each. The one Ian had in a picture is less, $20 each, and you need two for 5V of either.
For the +/-15, seems like a good reason to finally build some salas shunts I bought the parts for be never used.
Randy
@Markw4, I think any expectation that one can get a $250 DAC that rivals ones costing $1000 and more is unrealistic. One gets what one pays for. Even just adding a couple of 5V iFi iPower adds another $100, so adding those to the base $260 Katana makes it a $450 DAC including an RPi 2B and shipping. A case, an isolator, and a 3rd iFi bring it to $550. I think it will sound pretty good at the no-isolator 2-supply level, but based on my limited down-quality supply experience with the Katana, a 4-supply setup even using the same supplies for the 3 5V ones will be a good step up.
Still, if you haven't read the review series I mentioned in a post on the main Katana thread, do so just to get the comments and test results of supply upgrades to those units. What they reported (and in my experience), better supplies produced better sonics. BUT as I found out, what is the better supply for a given setup may not be what one thinks.
OTOH, I don't believe one needs to duplicate my setup to get good performance out of the latest Katana. I haven't tried any lower cost supplies yet with the Katana and I can't comment on the SQ with them yet. I can say I got significant SQ differences between the 8 power configurations I've run so Katanas on far, confirming that power does matter with it. Of course only the full-monty gave what I considered 'break-through' sound. BUT it was not the most expensive of the options I tried by quite a bit!
I will agree with @cdsgames that one of two the largest bang for the buck upgrades from a 2 supplies/Katana only basic configuration will be adding a good +-15V supply for the output stages. I heard that back when I experimented with the Dial DAC. I first powered it using a Silent Switcher supply, another DC-DC converter producing +-15V from a 5V-9V input. That DAC showed some promise, but was nothing special in that configuration. Swapping in a +-15V set of shunt regulators (similar to simplified Salas) and fed from the same raw DC supply as I'm using for the Katana was a good upgrade and it became a very enjoyable DAC most of the time with that power. Of course, the stock Dial derives the 2 rails for the DAC chip (+3.3v/+5v in the version I had, +3.3V/+6V in the later version) from the +15V rail, so that supply likely has a larger effect on the sound. AND I heard the benefit of a separate +-15V supply very clearly with the Katana... half of those 8 setups were with the DC-DC converters, the other half were the same basic 3 supplies (RPi, isolator/DAC, microprocessor) and adding my +-15V supply.
I am curious how much simpler and less expensive you can go than my +-15V setup and still reap good benefits. The Katana already has 2 stages of regulation for the output stages. My +-15V supply may be significant overkill.
IMHO the other bang for the buck upgrade will be an isolator and an added supply for the RPi. As the isolators (first Ian's, then Allo's) became available, I tried them with all of the RPi-sourced setups I had at the time (modified HiFiBerry and Mamboberry, stock and hot-rod Dial DACs, Boss and Piano 2.1, and my modified Soekris setup) and even though I already had separate supplies for the RPi and the DAC, in every case the isolator lowered the apparent background noise and made it easier to hear subtle details when added.
One worthwhile reason to use a 4 supply setup on a Katana (RPi 5V, DAC/isolator 5V, microprocessor board 5V, and +-15V output stages) is that the current requirements becomes much more reasonable for each supply and MAY even allow 'budget' supplies to produce good results for the 5V supplies. The Jameco 5V/1A linear-regulated supply at under $25 each then may become a useful choice. AND if one is DIY-handy, the mods I've done to them (upgrading the rectifier diodes along with the filter caps before and after the regulator and adding a John Swenson transformer ringing snubber along with an AC filter cap) takes them up a level.
@Randytsuch, I agree that direct LiFePO4 batteries and Ultracaps beat traditional supplies when used correctly. One of the reasons I haven't pursued them on the Katana so far is an impression (from what I've read and from my experience in using a direct Ultracap setup with one DAC, Ian's ES9028Q2M prototype) is that they work best when used direct, bypassing on-board regulators. Looking at the Katana boards I think that will be a challenging modification because of the fairly sophisticated and more complex than average power supply network designed to provide the best from lower-cost supplies. Likely worth it, but until someone blazes that trail, one takes a chance of damaging the $260 unit. Still, depending on their cost, Ian's battery and Ultracap supplies should be VERY good alternatives to standard supplies for a non-modified Katana. And a 3-battery or 3-Ultracap float-charged supply setup coupled with a good supply behind those +-15V Salas you mentioned should kick butt!
I'll see if I can find some time over the next several days to price power setups from the other vendors I mentioned. AND there's the supplies Allo is developing, which if history is any indication, should be good performers at surprising prices
Any more suggestions on other kit, DIY, or ready-built supply options?
Greg in Mississippi
Still, if you haven't read the review series I mentioned in a post on the main Katana thread, do so just to get the comments and test results of supply upgrades to those units. What they reported (and in my experience), better supplies produced better sonics. BUT as I found out, what is the better supply for a given setup may not be what one thinks.
OTOH, I don't believe one needs to duplicate my setup to get good performance out of the latest Katana. I haven't tried any lower cost supplies yet with the Katana and I can't comment on the SQ with them yet. I can say I got significant SQ differences between the 8 power configurations I've run so Katanas on far, confirming that power does matter with it. Of course only the full-monty gave what I considered 'break-through' sound. BUT it was not the most expensive of the options I tried by quite a bit!
I will agree with @cdsgames that one of two the largest bang for the buck upgrades from a 2 supplies/Katana only basic configuration will be adding a good +-15V supply for the output stages. I heard that back when I experimented with the Dial DAC. I first powered it using a Silent Switcher supply, another DC-DC converter producing +-15V from a 5V-9V input. That DAC showed some promise, but was nothing special in that configuration. Swapping in a +-15V set of shunt regulators (similar to simplified Salas) and fed from the same raw DC supply as I'm using for the Katana was a good upgrade and it became a very enjoyable DAC most of the time with that power. Of course, the stock Dial derives the 2 rails for the DAC chip (+3.3v/+5v in the version I had, +3.3V/+6V in the later version) from the +15V rail, so that supply likely has a larger effect on the sound. AND I heard the benefit of a separate +-15V supply very clearly with the Katana... half of those 8 setups were with the DC-DC converters, the other half were the same basic 3 supplies (RPi, isolator/DAC, microprocessor) and adding my +-15V supply.
I am curious how much simpler and less expensive you can go than my +-15V setup and still reap good benefits. The Katana already has 2 stages of regulation for the output stages. My +-15V supply may be significant overkill.
IMHO the other bang for the buck upgrade will be an isolator and an added supply for the RPi. As the isolators (first Ian's, then Allo's) became available, I tried them with all of the RPi-sourced setups I had at the time (modified HiFiBerry and Mamboberry, stock and hot-rod Dial DACs, Boss and Piano 2.1, and my modified Soekris setup) and even though I already had separate supplies for the RPi and the DAC, in every case the isolator lowered the apparent background noise and made it easier to hear subtle details when added.
One worthwhile reason to use a 4 supply setup on a Katana (RPi 5V, DAC/isolator 5V, microprocessor board 5V, and +-15V output stages) is that the current requirements becomes much more reasonable for each supply and MAY even allow 'budget' supplies to produce good results for the 5V supplies. The Jameco 5V/1A linear-regulated supply at under $25 each then may become a useful choice. AND if one is DIY-handy, the mods I've done to them (upgrading the rectifier diodes along with the filter caps before and after the regulator and adding a John Swenson transformer ringing snubber along with an AC filter cap) takes them up a level.
@Randytsuch, I agree that direct LiFePO4 batteries and Ultracaps beat traditional supplies when used correctly. One of the reasons I haven't pursued them on the Katana so far is an impression (from what I've read and from my experience in using a direct Ultracap setup with one DAC, Ian's ES9028Q2M prototype) is that they work best when used direct, bypassing on-board regulators. Looking at the Katana boards I think that will be a challenging modification because of the fairly sophisticated and more complex than average power supply network designed to provide the best from lower-cost supplies. Likely worth it, but until someone blazes that trail, one takes a chance of damaging the $260 unit. Still, depending on their cost, Ian's battery and Ultracap supplies should be VERY good alternatives to standard supplies for a non-modified Katana. And a 3-battery or 3-Ultracap float-charged supply setup coupled with a good supply behind those +-15V Salas you mentioned should kick butt!
I'll see if I can find some time over the next several days to price power setups from the other vendors I mentioned. AND there's the supplies Allo is developing, which if history is any indication, should be good performers at surprising prices
Any more suggestions on other kit, DIY, or ready-built supply options?
Greg in Mississippi
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Understood about power quality, but it sure would be helpful to get a better idea of what it needs. It would be easy for me to hook it up to LM317/LM337 type power. I could also maybe do LT1963 type regulation, or LT3045x regulators. I could put them all in series too I guess. It would be helpful if I knew what I need to do in advance rather than having to experiment with it. Of course, the easy way out would be for me to use what Allo recommends or what I can find on-hand, and just say the dac didn't come with power supplies or much recommendations so I will test it and compare it with the other dacs here as I expect most users would be powering it.
Although that would easy, and it might be how other users would power it, it still might not be a very fair test. I am trying to make a really good sounding modded dac, and and if Katana does not come out well enough in the comparison I would feel much better about recommending that people buy Katana if I knew both how it sounds as most people would power it, and how it sounds at its best. Maybe I won't be able to do the latter, don't know. For one thing, I would expect that high quality external 15v power can only help so much. The dac board is probably as critical as the output stage board. The dac board has the very critical AVCC supplies, and other supplies that need to be very clean such as for the clocks, and the other dac chip analog and digital power inputs.
In case it turns out I can't get it sounding its best, may I ask your opinion about the best you had Katana sounding? As good as TP? Almost? Where would you say it sits in your rankings?
Although that would easy, and it might be how other users would power it, it still might not be a very fair test. I am trying to make a really good sounding modded dac, and and if Katana does not come out well enough in the comparison I would feel much better about recommending that people buy Katana if I knew both how it sounds as most people would power it, and how it sounds at its best. Maybe I won't be able to do the latter, don't know. For one thing, I would expect that high quality external 15v power can only help so much. The dac board is probably as critical as the output stage board. The dac board has the very critical AVCC supplies, and other supplies that need to be very clean such as for the clocks, and the other dac chip analog and digital power inputs.
In case it turns out I can't get it sounding its best, may I ask your opinion about the best you had Katana sounding? As good as TP? Almost? Where would you say it sits in your rankings?
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Greg, Wanted ask you about one other thing re Silent Switcher. I have a couple of those and although they are pretty good, I have found that it can matter a lot depending on how they are powered. If powered from a switch mode 5v supply, ground conducted and radiated noise can work its way up to the load. It can just sort of bypasses the regulation and filtering on Silent Switcher, something that can be confirmed by tracing the noise along the wiring using a battery powered shortwave radio tuned to maybe a couple of MHz. Therefore, I would only recommend using SS if powered from a linear supply. Not sure how you powered the one you tried using with Katana?
Greg
So I know lifepo4 are better supplying power directly into the circuit, adding a reg in front will degrade them. But to me the question is how does a lifepo4 or supercap based PS compare to your Jensen cap MP Audio reg supplies?
The more I think about it, the more I think supercap is the way to go for a 5V PS. Lifepo4 is a compromise at 5V, much better at 3 to 3.3V.
Caps should care less about the voltage, as long as you don't exceed their rating. For a battery, 2.5V is way down on its capacity curve.
So once the dacs go on general sale, if I actually follow through (lol), current plans would be to build some simple 5V linear regs to feed supercaps to power the pi and dac. And the salas for +/- 15V.
Ian put out a schematic for a supercap board in one of his threads, its a pretty simple board.
Randy
So I know lifepo4 are better supplying power directly into the circuit, adding a reg in front will degrade them. But to me the question is how does a lifepo4 or supercap based PS compare to your Jensen cap MP Audio reg supplies?
The more I think about it, the more I think supercap is the way to go for a 5V PS. Lifepo4 is a compromise at 5V, much better at 3 to 3.3V.
Caps should care less about the voltage, as long as you don't exceed their rating. For a battery, 2.5V is way down on its capacity curve.
So once the dacs go on general sale, if I actually follow through (lol), current plans would be to build some simple 5V linear regs to feed supercaps to power the pi and dac. And the salas for +/- 15V.
Ian put out a schematic for a supercap board in one of his threads, its a pretty simple board.
Randy
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Joined 2009
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Well, my experience is quite different. In fact, Audio is one of those areas where I'm firmly convinced you do NOT get what you pay for, unless you place a very high value on thick Aluminium plates and brand names that is:
http://www.bryston.com/products/digital_audio/BDP-Pi.html
I'm hoping to assemble an RPi music source as a high quality source for my main listening pleasure. It's not obvious when there are lots of choices. What I want to hear about is the HAT DAC that has been very well engineered, with on-board scrubbing of power supplies etc. so that I don't have to baby the thing with very expensive external parts. It should not need more than a solid supply. If I learn that all sorts of tweaks and expensive support circuits are required for a HAT DAC then I lose interest very rapidly in the quality of it's design. Sure, there are those who just have to tweak and are convinced they have gained some 'audible' improvement that makes them happy - I'm not looking to pour cold water on anybody's fun in that regard, just looking for a solid solution.
Is the Katana a well engineering product ?
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Some responses...
@ktham, thanks for the tip on those Glassware kits. I'll add them to my list of useful low-cost power supply kit alternatives. Compared to the K&K kits, I might personally lean towards the K&K units due to the all-in-one design, the included transformer, their 'charge-slope lowering resistor', and their use of the Linear Technology LT3083/3080 regulators, which I found to be a sonic upgrade in supplies powering computer peripherals (HDDs, SSDs, small processor boards such as the RPi) over more standard 317/337-styled regulators including the Linear Tech versions. But the difference is not huge and these units will be good alternatives.
@Markw4, my takeaway from the 'limited' power supply trials I did is that the Katana will work with virtually any compliant supply setup... but that it will respond well to whatever improvements one cares to throw at it. That is a bit surprising to me given how much effort Allo has spent working to make it sound as good as it can when used with low-cost supplies. BUT the differences I've heard so far are pretty marked. IF I were starting from scratch and did not want to go the multiple-paralleled LT3045 route ala' MPAudio, I'd do something with Linear Tech LT3080/3083 or the LT1963 you mentioned (I've had great results with the LT3080/3083 in a number of builds and have some LT1963 here to try, but have not yet). A 3 5V rail supply with these (using the LT3080 from a fully separate raw DC supply for the RPi rail) and a +-15V supply using the Salas, Sparkos, Belleson, or new Dexa discrete regulators should sound spanking! The 3 5V supplies could be as simple as 3 of the K&K Audio, Twisted Pear Audio, AMD, or Glassware kits.
As for where the Katana compares to my other really good digital setups, I have to hedge and say it is in the same strata as my top units... my 2 Twisted Pear setups, Ian's prototype ES9028Q2M DAC, and my modified Soekris. I hedge partly because I haven't done a lot of direct comparisons between them (most of my limited listening time August-October was comparing various versions of Katana). AND because I have a number of planned tweaks and upgrades to both the TP and Soekris setups that I expect will lift them some (though I don't have any planned mods to the Katana). Also they each sound a bit different from each other. I am pretty sure I could distinguish each in a blind test (not that I am into such), but I am also comfortable saying all are good and musically satisfying for me.
The Soekris and TP setups DO all use the exact same raw DC supplies as I'm running on the Katana and described earlier in this thread... I built 2 digital-source 'power-bases' on a couple of bamboo cutting boards with 8 raw DC supplies providing 9 different rails with various selected high-quality connectors for the various rails. The 2 'power-bases' are somewhat different in that the later one uses 4 separate toriodal transformers for the 4 main DAC supplies instead of the 2 Hammond transformers with dual secondaries as described above, but they interface to the digital source gear in the same ways using the same connector sets.
You can see pictures and some details of some of these builds in these:
Ian ES9028Q2M w/Ultracaps: ES9018K2M, ES9028Q2M, 9038Q2M DSD/I2S DAC HATs for Raspberry Pi
Twisted Pear setups starting at this post: Asynchronous I2S FIFO project, an ultimate weapon to fight the jitter
Modified Soekris starting at this post: Soekris' DAC implementations
A picture of my SDTrans384 -> Soekris setup with one of my power supply setups towards the end of this post (the other pix are of the reference system of the Japanese designer of the SDTrans384 SD Card Player): FORGETTING the Digital to Analog conversion part, what is BEST Digital source? - Page 8 - General Forum - Computer Audiophile
On the Silent Switcher, I only tried it once with a generic 5V SMPS supply... didn't need to repeat that. The iFi iPower 5V was better, though I preferred one of my modified Jameco 5V/1A linear-regulated supplies. I got the best results from the SS powering it with an Uptone Audio LPS-1.2. AND I did not try it with the Katana (sorry I wasn't clear about that). I did those comparisons on a stock Dial DAC on an RPi -> IsolatorPi -> Kali stack. Even at it's best with the LPS-1.2, the same raw linear supply I used on the Katana feeding a +-15V pair of simple shunt regulators was a significant step up. With any use of the Silent Switcher, I'd put the Dial near the top of my 'mid-fi' setups most of the time. With the good linear supply, I'd put it at the bottom of my 'hi-end' setups, again most of the time.
I HAD planned to try the Silent Switcher as a +-15V supply for the Katana, but the sonic differences I heard between using the on-board DC-DC supplies for the +-15V versus my linear +-15V supplies was similar, if not as large in magnitude, as I heard on the Dial DAC. Based on that, I don't believe the Silent Switcher +-15V would be an upgrade over the on-board DC-DC converters.
@Randytsuch, honestly I have not directly compared the use of Ian's trial Ultracap supplies against my AC-connected supplies AND I've only used one on one DAC, Ian's ES9028Q2M prototype. BUT the 3.3V Ultracap supply was a significant lift above using a good (LT3042) regulator fed from an Uptone Audio LPS-1.2. AND I have compared that style setup to the AC-connected supplies (with various regulation schemes) and generally for low-current digital circuits (isolators, Kali, low-power-consuming DACs) the LPS-1.2 beats my supplies. In a very few situations I found I got slightly better dynamics with the AC-connected supply, though slightly higher noise (such as with my modified Soekris DAM1021s) and stick with them there. OTOH, with the thought that my upgrade to the PS Audio P15 AC regenerator may have improved the relative 'goodness' of the AC-connected supplies, I need to redo those comparisions.
Still, used direct in that one application, the Ultracaps are a walk for me compared to either my AC supplies or the LPS-1.2s through a regulator. OTOH, I did see John Keny's comments on TirNaHiFi that for him there were some tradeoffs between Ultracaps and LiFePO4 direct and he's not yet settled on which he prefers. Watching that closely.
What this is leading me to is that I will need to expand the trials and comparisons of various power supply schemes powering the Katana to include non-direct Ultracaps and LiFePO4 setups, using various float-charging schemes. I do have 3 of Ian's trial Ultracap boards here, so I can do the 2 Katana 5V supplies using them float-charged by LPS-1.2s as a comparison point. AND actually also do the same using LiFEPO4 (though they'd have to be 2 in series at 2.5V each... not likely at their best).
AND I want to also look at how we can derive some relative ratings of various schemes tested by different people, since we'll all want to do some different alternatives.
@toonjanssen, I do know Allo had to revise the isolator to make it bi-directional for the I2C signals. AND they revised it to work with the Katana DAC board for power. BUT your questions are better asked on the main Allo.com thread.
Finally, @Bigun, I'll reply to you later... sorry, running out of time now!
Later!
Greg in Mississippi
@ktham, thanks for the tip on those Glassware kits. I'll add them to my list of useful low-cost power supply kit alternatives. Compared to the K&K kits, I might personally lean towards the K&K units due to the all-in-one design, the included transformer, their 'charge-slope lowering resistor', and their use of the Linear Technology LT3083/3080 regulators, which I found to be a sonic upgrade in supplies powering computer peripherals (HDDs, SSDs, small processor boards such as the RPi) over more standard 317/337-styled regulators including the Linear Tech versions. But the difference is not huge and these units will be good alternatives.
@Markw4, my takeaway from the 'limited' power supply trials I did is that the Katana will work with virtually any compliant supply setup... but that it will respond well to whatever improvements one cares to throw at it. That is a bit surprising to me given how much effort Allo has spent working to make it sound as good as it can when used with low-cost supplies. BUT the differences I've heard so far are pretty marked. IF I were starting from scratch and did not want to go the multiple-paralleled LT3045 route ala' MPAudio, I'd do something with Linear Tech LT3080/3083 or the LT1963 you mentioned (I've had great results with the LT3080/3083 in a number of builds and have some LT1963 here to try, but have not yet). A 3 5V rail supply with these (using the LT3080 from a fully separate raw DC supply for the RPi rail) and a +-15V supply using the Salas, Sparkos, Belleson, or new Dexa discrete regulators should sound spanking! The 3 5V supplies could be as simple as 3 of the K&K Audio, Twisted Pear Audio, AMD, or Glassware kits.
As for where the Katana compares to my other really good digital setups, I have to hedge and say it is in the same strata as my top units... my 2 Twisted Pear setups, Ian's prototype ES9028Q2M DAC, and my modified Soekris. I hedge partly because I haven't done a lot of direct comparisons between them (most of my limited listening time August-October was comparing various versions of Katana). AND because I have a number of planned tweaks and upgrades to both the TP and Soekris setups that I expect will lift them some (though I don't have any planned mods to the Katana). Also they each sound a bit different from each other. I am pretty sure I could distinguish each in a blind test (not that I am into such), but I am also comfortable saying all are good and musically satisfying for me.
The Soekris and TP setups DO all use the exact same raw DC supplies as I'm running on the Katana and described earlier in this thread... I built 2 digital-source 'power-bases' on a couple of bamboo cutting boards with 8 raw DC supplies providing 9 different rails with various selected high-quality connectors for the various rails. The 2 'power-bases' are somewhat different in that the later one uses 4 separate toriodal transformers for the 4 main DAC supplies instead of the 2 Hammond transformers with dual secondaries as described above, but they interface to the digital source gear in the same ways using the same connector sets.
You can see pictures and some details of some of these builds in these:
Ian ES9028Q2M w/Ultracaps: ES9018K2M, ES9028Q2M, 9038Q2M DSD/I2S DAC HATs for Raspberry Pi
Twisted Pear setups starting at this post: Asynchronous I2S FIFO project, an ultimate weapon to fight the jitter
Modified Soekris starting at this post: Soekris' DAC implementations
A picture of my SDTrans384 -> Soekris setup with one of my power supply setups towards the end of this post (the other pix are of the reference system of the Japanese designer of the SDTrans384 SD Card Player): FORGETTING the Digital to Analog conversion part, what is BEST Digital source? - Page 8 - General Forum - Computer Audiophile
On the Silent Switcher, I only tried it once with a generic 5V SMPS supply... didn't need to repeat that. The iFi iPower 5V was better, though I preferred one of my modified Jameco 5V/1A linear-regulated supplies. I got the best results from the SS powering it with an Uptone Audio LPS-1.2. AND I did not try it with the Katana (sorry I wasn't clear about that). I did those comparisons on a stock Dial DAC on an RPi -> IsolatorPi -> Kali stack. Even at it's best with the LPS-1.2, the same raw linear supply I used on the Katana feeding a +-15V pair of simple shunt regulators was a significant step up. With any use of the Silent Switcher, I'd put the Dial near the top of my 'mid-fi' setups most of the time. With the good linear supply, I'd put it at the bottom of my 'hi-end' setups, again most of the time.
I HAD planned to try the Silent Switcher as a +-15V supply for the Katana, but the sonic differences I heard between using the on-board DC-DC supplies for the +-15V versus my linear +-15V supplies was similar, if not as large in magnitude, as I heard on the Dial DAC. Based on that, I don't believe the Silent Switcher +-15V would be an upgrade over the on-board DC-DC converters.
@Randytsuch, honestly I have not directly compared the use of Ian's trial Ultracap supplies against my AC-connected supplies AND I've only used one on one DAC, Ian's ES9028Q2M prototype. BUT the 3.3V Ultracap supply was a significant lift above using a good (LT3042) regulator fed from an Uptone Audio LPS-1.2. AND I have compared that style setup to the AC-connected supplies (with various regulation schemes) and generally for low-current digital circuits (isolators, Kali, low-power-consuming DACs) the LPS-1.2 beats my supplies. In a very few situations I found I got slightly better dynamics with the AC-connected supply, though slightly higher noise (such as with my modified Soekris DAM1021s) and stick with them there. OTOH, with the thought that my upgrade to the PS Audio P15 AC regenerator may have improved the relative 'goodness' of the AC-connected supplies, I need to redo those comparisions.
Still, used direct in that one application, the Ultracaps are a walk for me compared to either my AC supplies or the LPS-1.2s through a regulator. OTOH, I did see John Keny's comments on TirNaHiFi that for him there were some tradeoffs between Ultracaps and LiFePO4 direct and he's not yet settled on which he prefers. Watching that closely.
What this is leading me to is that I will need to expand the trials and comparisons of various power supply schemes powering the Katana to include non-direct Ultracaps and LiFePO4 setups, using various float-charging schemes. I do have 3 of Ian's trial Ultracap boards here, so I can do the 2 Katana 5V supplies using them float-charged by LPS-1.2s as a comparison point. AND actually also do the same using LiFEPO4 (though they'd have to be 2 in series at 2.5V each... not likely at their best).
AND I want to also look at how we can derive some relative ratings of various schemes tested by different people, since we'll all want to do some different alternatives.
@toonjanssen, I do know Allo had to revise the isolator to make it bi-directional for the I2C signals. AND they revised it to work with the Katana DAC board for power. BUT your questions are better asked on the main Allo.com thread.
Finally, @Bigun, I'll reply to you later... sorry, running out of time now!
Later!
Greg in Mississippi
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@Bigun,
On the Bryston BDP-Pi...first, I think Darko's review laid out the value proposition of the BDP-Pi very well. They are selling something that is MUCH more than a basic RPi setup, including a power supply, a custom multiple-mode output board, a substantial and pretty case, a nice screen, and very functional custom software they will have to support for many years. Many will want and value those things. I don't. AND I can DIY, so it's not a product that is useful to me. And apparently you don't either. Cool. Be kind to those who can't or don't care to DIY like we do, value products such as that, and can and will buy them.
Also, Bryston is a company that sells through distributors and retail outlets, which in my experience means a 5x-6x markup over the cost of the parts & components plus labor to produce the product. So $250-$300 in parts and components. Seems like they've done a pretty good job in sourcing to get it to that price level. AND I bet they will lose their shirts on product support for that unit... just IMHO.
So I disagree... there is value in that unit. I don't need that value and wouldn't buy one. BUT I won't put the unit down either.
On whether the Katana is a solid and well engineered unit... AFAIK, there are no units out there that can't be improved by bettering the power supply. SOME at a pretty atmospheric price level cannot be improved much, but I expect units like that to be in the $6,000-$10,000 range or more. Read the review series I linked-to in this post on the main Katana thread:
New FIFO buffer for RPI/SBCs
The reviewer got good upgrades adding $1,000-$2,600 power supplies to $2,200-$2,500 DACs, making them strongly competitive with 5,000-$10,000 DACs.
I consider both Mytech and iFi to be companies that know how to engineer good products.
I would not expect Allo to do in the $260 Katana what these companies can't do in their DACs costing 10x more.
Is it the Katana a well-engineered product? IMHO, yes. Of course there are avenues of improvement, but none within its current or any realistic price increase that will make it immune to differences in power supplies. AND of course, it is sold both without any power supplies AND with a number of options on how you can configure and connect those supplies, you have a lot of options. You get to choose how good you want to make it!
With power supplies, you get what you pay for. The cost of power supplies is one of the largest components in the cost of higher-end audio gear. Back in that series of reviews, read the comments from Ayre on the differences between their $5,500 QX-8 and $10,000 QX-9. MUCH of it is in the power supplies. AND take a look at those supplies in the Denafrip Terminator, one's I'd drool over, a $4,300 unit produced in a low-cost supplier country.
Please don't take this response as a diss or a put-down. It is not. AND my experience is that there is no equipment out there cannot be improved by better power supplies. AND that will cost $$$.
Later!
Greg in Mississippi
On the Bryston BDP-Pi...first, I think Darko's review laid out the value proposition of the BDP-Pi very well. They are selling something that is MUCH more than a basic RPi setup, including a power supply, a custom multiple-mode output board, a substantial and pretty case, a nice screen, and very functional custom software they will have to support for many years. Many will want and value those things. I don't. AND I can DIY, so it's not a product that is useful to me. And apparently you don't either. Cool. Be kind to those who can't or don't care to DIY like we do, value products such as that, and can and will buy them.
Also, Bryston is a company that sells through distributors and retail outlets, which in my experience means a 5x-6x markup over the cost of the parts & components plus labor to produce the product. So $250-$300 in parts and components. Seems like they've done a pretty good job in sourcing to get it to that price level. AND I bet they will lose their shirts on product support for that unit... just IMHO.
So I disagree... there is value in that unit. I don't need that value and wouldn't buy one. BUT I won't put the unit down either.
On whether the Katana is a solid and well engineered unit... AFAIK, there are no units out there that can't be improved by bettering the power supply. SOME at a pretty atmospheric price level cannot be improved much, but I expect units like that to be in the $6,000-$10,000 range or more. Read the review series I linked-to in this post on the main Katana thread:
New FIFO buffer for RPI/SBCs
The reviewer got good upgrades adding $1,000-$2,600 power supplies to $2,200-$2,500 DACs, making them strongly competitive with 5,000-$10,000 DACs.
I consider both Mytech and iFi to be companies that know how to engineer good products.
I would not expect Allo to do in the $260 Katana what these companies can't do in their DACs costing 10x more.
Is it the Katana a well-engineered product? IMHO, yes. Of course there are avenues of improvement, but none within its current or any realistic price increase that will make it immune to differences in power supplies. AND of course, it is sold both without any power supplies AND with a number of options on how you can configure and connect those supplies, you have a lot of options. You get to choose how good you want to make it!
With power supplies, you get what you pay for. The cost of power supplies is one of the largest components in the cost of higher-end audio gear. Back in that series of reviews, read the comments from Ayre on the differences between their $5,500 QX-8 and $10,000 QX-9. MUCH of it is in the power supplies. AND take a look at those supplies in the Denafrip Terminator, one's I'd drool over, a $4,300 unit produced in a low-cost supplier country.
Please don't take this response as a diss or a put-down. It is not. AND my experience is that there is no equipment out there cannot be improved by better power supplies. AND that will cost $$$.
Later!
Greg in Mississippi