Right now Nirvana is advancing very rapidly . This week we broke the sub uV level of noise on 0-20Khz from 0-2A. At 3A (full load) we have noise around 8uV and we think thats acceptable.
For most DACs (up to 0.6A) noise is at 650nV
Only one 5V output for multiple reasons. That is final.
Of course , I dont think thats very important once you get in uV range. What we took great care of is common mode noise , leakage current and output impedance .
Still we wont rush anything , more testing will be done by us and audio enthusiasts. We learned our lesson.
I estimate engineering samples in 1 month. FCC testing might delay us..
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any update on the isolator 2? hopefully it will coincide with katana 1.2. so i can recieve both my katana reolacement and the isolator.
question. Im using katana version 1. Will the acrylic casing be modified for v 1.2? Did you reposition some components that can impact the katana case v1.0 case?
Hey cdsgames,
I remember you briefly commenting on the Katana and bookshelf speakers. I'm currently running that setup (with a rythmik sub). It does feel like the Katana is very light on its feet and "gracefully cuts through the air" -- like a katana. Details and vocals really shine. However, it does feel like it lacks a little bit of authority. On one hand, the low frequencies are definitely present via my sub, and can certainly shake the house if desired. Yet, it still feels like it doesn't have the "weight" when listening to an orchestra bellow through a powerful passage.
I'm curious if your experience with your bookshelf speakers is similar to mine, and how v1.2 improves your listening experience on a pair of bookshelfs. Thanks!
Hello, i have the same feeling as you but with cheap China DAC ES9038q2m until I cut off simple opamp stage and replaced it by discrete hdam + diamond buffer stage, but on katana there is discrete out stage in class A so it should
sound very good... but i have big column speaker...
There are numerous things that come to mind affecting the low end and sound experience in general.
1. Power
If I recall it correctly the Class A output stage draws a bit less than 1A power.
And that's continuous power in the first place.
That puts much higher demands on a power supply.
Most HAT DACs you've seen so far draw a fragment of power in comparision.
You need to review the power situation.
2. DAC Quality
The higher the quality of the DAC. The cleaner things get.
The blur just disappears.
Usually u see the words "clinical" popping up.
Just to mention it. I do think quality full digital amps are the most clinical least colored sounding devices. That's why many people stay away from that great technology.
Your system and your brain needs to be able to cope with this clean experience. And yes - the low-end loses quite some weight (blur!) too.
3. System allignment
Once you swap a crucial part in the system, you need to review
and question the rest of the chain. Usually now other parts of the system become bottlenecks.
That happened to CDSGAMES when he realized that his bookshelve
speakers are not telling the whole truth anymore.
The low-end of bookshelve speakers is usually a faked low-end anyhow.
It'll be difficult to take that as a benchmark for judging a DAC.
4. Expectations
Some people might expect little wonders of that DAC. You better get that straight!
Although it's costing 4 times as much as most other known HATs.
It won't sound 4 times as good. You might gain 5%-10% over your Boss setup.
For audiophile minded persons 10% will be well worth it.
On mediocre systems e.g. a Boss will continue to do a very good job.
You don't put a Hemi in a Beetle!
5. Operation
Break-in time - as discussed earlier is about 2 weeks.
I experienced that the DAC (class-A outputstage !) needs to warm up.
20-30 minutes will do.
Better keep that in mind before doing any serious listening tests.
Make also sure that your OS/SW setup is at its best. Especially the low-end
can gain quite a bit if the setup is done right. For now I didn't have
a chance to review how much Katana responds on OS&SW optimizations.
6. Design
Yep. There can also be issues related to the DAC design. The more people
are reporting the same issue, the higher the probability that there is an issue.
I guess Allo will have a very close look at this.
Bottom line. Introducing a new device into a well tuned chain is more
then just swapping box a against box b. It'll be a new project. Good luck with that!
Enjoy.
1. Power
If I recall it correctly the Class A output stage draws a bit less than 1A power.
And that's continuous power in the first place.
That puts much higher demands on a power supply.
Most HAT DACs you've seen so far draw a fragment of power in comparision.
You need to review the power situation.
2. DAC Quality
The higher the quality of the DAC. The cleaner things get.
The blur just disappears.
Usually u see the words "clinical" popping up.
Just to mention it. I do think quality full digital amps are the most clinical least colored sounding devices. That's why many people stay away from that great technology.
Your system and your brain needs to be able to cope with this clean experience. And yes - the low-end loses quite some weight (blur!) too.
3. System allignment
Once you swap a crucial part in the system, you need to review
and question the rest of the chain. Usually now other parts of the system become bottlenecks.
That happened to CDSGAMES when he realized that his bookshelve
speakers are not telling the whole truth anymore.
The low-end of bookshelve speakers is usually a faked low-end anyhow.
It'll be difficult to take that as a benchmark for judging a DAC.
4. Expectations
Some people might expect little wonders of that DAC. You better get that straight!
Although it's costing 4 times as much as most other known HATs.
It won't sound 4 times as good. You might gain 5%-10% over your Boss setup.
For audiophile minded persons 10% will be well worth it.
On mediocre systems e.g. a Boss will continue to do a very good job.
You don't put a Hemi in a Beetle!
5. Operation
Break-in time - as discussed earlier is about 2 weeks.
I experienced that the DAC (class-A outputstage !) needs to warm up.
20-30 minutes will do.
Better keep that in mind before doing any serious listening tests.
Make also sure that your OS/SW setup is at its best. Especially the low-end
can gain quite a bit if the setup is done right. For now I didn't have
a chance to review how much Katana responds on OS&SW optimizations.
6. Design
Yep. There can also be issues related to the DAC design. The more people
are reporting the same issue, the higher the probability that there is an issue.
I guess Allo will have a very close look at this.
Bottom line. Introducing a new device into a well tuned chain is more
then just swapping box a against box b. It'll be a new project. Good luck with that!
Enjoy.
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Regarding going from blurry to clinical, it turns out clinical isn't the end of the line for modern dacs. It is an intermediate stage where some of the usual dac problems have been fixed, but not all. There are dacs that are neither blurry nor clinical. They cost more and at first they sound great. Then you realize they just sound like all dacs should sound, like no dac at all, which includes sounding better than good vinyl. Yet, music played through the best dacs sounds much better than live music. Why? Because the best albums are meticulously produced to sound much better than is possible live, but very people ever get to hear them without blur, or maybe clinical effects. Right now, the entry level into the really good dacs starts at maybe around $2,000 for one stereo dac, IMHO. We need to keep working on getting that cost down, but its not easy for a lot of different reasons.
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Probably, I should have added that one can spend quite a lot more than $2,000 for one stereo dac and still not get better than clinical sound quality. Price is no guarantee of quality. But, there does seem to be a minimum price for it. Maybe take a look at the Stereophile recommended equipment list for 2018, in the dac section, for some that might be worth listening to. Of course, trying to find such boxes to audition may be nearly impossible, given that good hi-fi shops hardly exist in today's world.
I just set up my Digione transport a couple of days ago. Now I go and look at Allo's website and they have a Digione Signature transport for sale.
DigiOne Signature Clean Power SPDIF Out
It also uses 2 power supplies instead of one for the original Digione. I like the simplicity of plugging in only one power cable. I am using multiple supplies in my odroidC2/Isolator Pi/Kali/Dam1021 setup, but that will be inside a single enclosure. I am running the Digione into my AVR currently and have it in a plastic enclosure from Allo which looks fine (other than the fact the predrilled holes didn't match up). A single power connection from the iFi power works well. An additional power supply means trying to find an additional power plug on an already full power strip.
DigiOne Signature Clean Power SPDIF Out
It also uses 2 power supplies instead of one for the original Digione. I like the simplicity of plugging in only one power cable. I am using multiple supplies in my odroidC2/Isolator Pi/Kali/Dam1021 setup, but that will be inside a single enclosure. I am running the Digione into my AVR currently and have it in a plastic enclosure from Allo which looks fine (other than the fact the predrilled holes didn't match up). A single power connection from the iFi power works well. An additional power supply means trying to find an additional power plug on an already full power strip.
Independant review and measurement of Katana by Amir .
Review and Measurements of Allo Katana and ApplePi Raspberry Pi DACs | Audio Science Review (ASR) Forum
Review and Measurements of Allo Katana and ApplePi Raspberry Pi DACs | Audio Science Review (ASR) Forum
Just a quick update. (another)
Working with Andrew , we identified the issue with some hi frequency noise that was audible on smaller speakers. Our LPF rolloff was higher than usual and we changed one R and its all gone
Meanwhile we looked at our analog stage and cleaned further the rails (on opamps) to about 700uV (with music on)
I am waiting for the final clean board to listen to it from India (my own test up has only the LPF fixed).
SQ has improved dramatically on the smaller speakers and medium improvement on main test setup (with LPF)
I will test the Rasmussen filter (with LPF that I already fixed) and with dual rails cleaned further on Monday.
All "digitalis"/"fatiguing" is gone from sound already but I want to fully test it with all mods before releasing. THD+N has improved .
Katana is coming . Sorry for all this but I put too much trust in machine testing not enough on human hearing.
Working with Andrew , we identified the issue with some hi frequency noise that was audible on smaller speakers. Our LPF rolloff was higher than usual and we changed one R and its all gone
Meanwhile we looked at our analog stage and cleaned further the rails (on opamps) to about 700uV (with music on)
I am waiting for the final clean board to listen to it from India (my own test up has only the LPF fixed).
SQ has improved dramatically on the smaller speakers and medium improvement on main test setup (with LPF)
I will test the Rasmussen filter (with LPF that I already fixed) and with dual rails cleaned further on Monday.
All "digitalis"/"fatiguing" is gone from sound already but I want to fully test it with all mods before releasing. THD+N has improved .
Katana is coming . Sorry for all this but I put too much trust in machine testing not enough on human hearing.
I made an enquiry with a company about integrating my RPi with a Katana and power supply together with 2x icepower 300AS1 as a dual mono in either a single or two separate chassis. They seem to have come across the Katana and were experimenting with their power supply.
They were, however, concerned that the digital volume control on the Katana is potentially flaky in that it could end up at 100% and potentially blowing speakers if connected directly to power amps?
They were, however, concerned that the digital volume control on the Katana is potentially flaky in that it could end up at 100% and potentially blowing speakers if connected directly to power amps?