does not matter, use an analogue one....
hi Hermann,
it is not sooo important which one. ( I use the sjöström, much to expensive!)
but I have build 5 Najdas with " normal" analogue Power supplys! Everyone ist much better than the switched Power Supplies....even expensive ones like Traco etc.
Regards Ulf
hi Hermann,
it is not sooo important which one. ( I use the sjöström, much to expensive!)
but I have build 5 Najdas with " normal" analogue Power supplys! Everyone ist much better than the switched Power Supplies....even expensive ones like Traco etc.
Regards Ulf
better?
Hi Julf,
for me a most tube amps sound better than transistors. In that way.
But may be its my taste?
regards Ulf
Hi Julf,
for me a most tube amps sound better than transistors. In that way.
But may be its my taste?
regards Ulf
Could be. Could also be there is no difference at all. In any case, not much to go on in trying to determine if there really is a difference, and if so, what kind of a difference.
Hi,
I read a little in this thread and I like the Najda project very much. I'am planning to build a Preamp with DSP functionality.
Unfortunately I read about sound problems.
See
http://www.diyaudio.com/forums/digi...p-xover-project-part-2-a-251.html#post4134554 at point 4
or
http://www.diyaudio.com/forums/digital-line-level/215379-dsp-xover-project-part-2-a-248.html#post4118658
Are these problems solved now?
I would use the digital (SP/DIF) and analoge inputs of Najda and the analoge outputs of Najda. The only problem I would have - there are no multiple analoge and digital inputs. I have to add an input selector with aprox. 3 SP/DIF and analoge inputs, which should be switchable by a remote control. Is there a simple way/solution to do that?
Regards Chris
I read a little in this thread and I like the Najda project very much. I'am planning to build a Preamp with DSP functionality.
Unfortunately I read about sound problems.
See
http://www.diyaudio.com/forums/digi...p-xover-project-part-2-a-251.html#post4134554 at point 4
or
http://www.diyaudio.com/forums/digital-line-level/215379-dsp-xover-project-part-2-a-248.html#post4118658
Are these problems solved now?
I would use the digital (SP/DIF) and analoge inputs of Najda and the analoge outputs of Najda. The only problem I would have - there are no multiple analoge and digital inputs. I have to add an input selector with aprox. 3 SP/DIF and analoge inputs, which should be switchable by a remote control. Is there a simple way/solution to do that?
Regards Chris
Hi,
I read a bit in this thread, because I like the Najda project very much.
But I must ask a question about the sound quality. Some user posted problems:
http://www.diyaudio.com/forums/digi...-project-part-2-a-248.html#post4118658http://
or
http://www.diyaudio.com/forums/digi...p-xover-project-part-2-a-251.html#post4134554 at point 4
Are these problems solved now and Najda runs without faults?
I would use Najda as preamp. Unfortunately Najda has only one analoge chinch input and only one digital SP/DIF input. But I need approximately 3 chinch and 3 SP/DIF inputs.
I there a simple solution to add an imput selector which should switchable by remote control?
Regards
Chris
I read a bit in this thread, because I like the Najda project very much.
But I must ask a question about the sound quality. Some user posted problems:
http://www.diyaudio.com/forums/digi...-project-part-2-a-248.html#post4118658http://
or
http://www.diyaudio.com/forums/digi...p-xover-project-part-2-a-251.html#post4134554 at point 4
Are these problems solved now and Najda runs without faults?
I would use Najda as preamp. Unfortunately Najda has only one analoge chinch input and only one digital SP/DIF input. But I need approximately 3 chinch and 3 SP/DIF inputs.
I there a simple solution to add an imput selector which should switchable by remote control?
Regards
Chris
Hi Chris
Almost same configuration as pguerin. We have built about 10 devices in a group buy for very high end systems, with switching PS, everybody is happy with the sound.
The issue you mention is switching supply vs linear supply : everybody with experience will tell you that a good SMPS is as good as a linear one if properly designed. But the point is that very few, afaik, has built two units for a Najda and compared them. So it's more a problem of beliefs than facts based, I am afraid.
BR
Jean-Louis
Almost same configuration as pguerin. We have built about 10 devices in a group buy for very high end systems, with switching PS, everybody is happy with the sound.
The issue you mention is switching supply vs linear supply : everybody with experience will tell you that a good SMPS is as good as a linear one if properly designed. But the point is that very few, afaik, has built two units for a Najda and compared them. So it's more a problem of beliefs than facts based, I am afraid.
BR
Jean-Louis
Two issues with Raspberry Pi B+ Najda and Hypex UCD36MP
Hi everybody,
like many other people on this thread I'm building a little active speaker based on wonderful Najda.
Unfortunately I'm facing two issues:
First:
I was not yet able to connect a Raspberry PI B+ by I2S to Najda. There is no sound or just some very loud static noise. As for software, I'm using piCorePlayer.
Has anybody done that and might give some advice?
Second:
I use Najda in combination with two Hypex UCD36MP. Its a 6-channel amp, but I only use three of them. As I'm building a 2-way speaker, I go bridged in the bass. Now here comes the strange part of the story. When I only connect one amp to Najda, everything just works fine. As soon as I connect the second amp, I hear buzzing noise on both tweeters. Bass is fine, no problem. I can observe exactly the same behavior, when change the order. The buzzing noise is also there, when the second amp is disconnected from mains.
It's probably a ground issue, but I'm not having a clue how to solve this.
I'm writing on a technical documentation of the project, which I can provide for a very detailed description. But fist I post some pics for illustration (I hope this works the way I did it).
Front-View of "Najda-DSP":
Top-View of "Najda-DSP":
DSP & Speakers:
Any help is very much appreciated! I know it's a very short description of my project and I can give more detailed information if useful.
I already realized, that the sound will be absolutely blameless and it would be nice to build my own multiroom network music system.
Kind Regards
Fabian
Hi everybody,
like many other people on this thread I'm building a little active speaker based on wonderful Najda.
Unfortunately I'm facing two issues:
First:
I was not yet able to connect a Raspberry PI B+ by I2S to Najda. There is no sound or just some very loud static noise. As for software, I'm using piCorePlayer.
Has anybody done that and might give some advice?
Second:
I use Najda in combination with two Hypex UCD36MP. Its a 6-channel amp, but I only use three of them. As I'm building a 2-way speaker, I go bridged in the bass. Now here comes the strange part of the story. When I only connect one amp to Najda, everything just works fine. As soon as I connect the second amp, I hear buzzing noise on both tweeters. Bass is fine, no problem. I can observe exactly the same behavior, when change the order. The buzzing noise is also there, when the second amp is disconnected from mains.
It's probably a ground issue, but I'm not having a clue how to solve this.
I'm writing on a technical documentation of the project, which I can provide for a very detailed description. But fist I post some pics for illustration (I hope this works the way I did it).
Front-View of "Najda-DSP":
An externally hosted image should be here but it was not working when we last tested it.
Top-View of "Najda-DSP":
An externally hosted image should be here but it was not working when we last tested it.
DSP & Speakers:
An externally hosted image should be here but it was not working when we last tested it.
Any help is very much appreciated! I know it's a very short description of my project and I can give more detailed information if useful.
I already realized, that the sound will be absolutely blameless and it would be nice to build my own multiroom network music system.
Kind Regards
Fabian
Hi, am sorry that I can't agree with you. We have build one Najda with SMPS and one linear with the Sjöström super regulators. We compared both builds and there is a noticeable improvement in sound quality. In our case it was a reproducible fact and not a belief.
Regards
Sigi
Hi Sigi
You have gone the right way comparing, it's great. I have myself a Sjöstrom unit waiting to be assembled and a couple of Diyaudio Superreg backordered to do some testing myself. Two questions though:
- Did you find that linear supply for 5v digital brought the same improvement as the +/-12V for buffer ?
- I plan to use the same 5v also for feeding my WaveIO. Is it okay ?
BR
Jean-Louis
You have gone the right way comparing, it's great. I have myself a Sjöstrom unit waiting to be assembled and a couple of Diyaudio Superreg backordered to do some testing myself. Two questions though:
- Did you find that linear supply for 5v digital brought the same improvement as the +/-12V for buffer ?
- I plan to use the same 5v also for feeding my WaveIO. Is it okay ?
BR
Jean-Louis
We tested the Najda with the linear both simultaneously for 5V digital and +- 12V for buffer. Therefore I can't tell if the 5V digital brought the same improvement. I have the waveIO, the Amanero and the Exa U2i. I preferred the last one and I modified it in that way, that power is not supplied through the USB-Cable but with a separate linear PSU. I couldn' feed it with the 5V from the digital section because then I would have destroyed the isolation of the Exa.
In case of WaveIO if you use the non isolated connection I think you could feed it with the 5V of the digital section.
Regards
Sigi
I'm looking at some discrete op amps to try on the Najda and I am unsure which type would be best suited. Below is some info that is meant to help decide. Is anyone able to advise what would work best for the Najda's input and output op amps?
With thanks!
HOW TO CHOOSE THE OPA301(or OPA302) AND OPA2301(or OPA2302)
OPA301(or OPA302) and OPA2301(or OPA2302) are selected according to an opamp circuit impedance values.
1. OPA301(or OPA302): Use for the low impedance circuit
--- Feedback-Resistor is less than 1000 ohm
--- Headphone-Amp output circuit (only if the supply voltage is ± 5V or less)
--- However, due to high Supply Current (Quiescent Current), depending on the product, you need to check it even if the Supply Voltage is reduced.
2. OPA2301(or OPA2302): Use for a high impedance circuit
--- Feedback-Resistor is more than 1000 ohm
--- However, the Supply Current (Quiescent Current) is low.
3. If you do not know the value of the Feedback-Resistor or uncertain, the two, it is recommended that you choose to try the actual use.
Feedback Resistor is:
Resistor connected between the Negative Input and Out in opamp circuit.
With thanks!
HOW TO CHOOSE THE OPA301(or OPA302) AND OPA2301(or OPA2302)
OPA301(or OPA302) and OPA2301(or OPA2302) are selected according to an opamp circuit impedance values.
1. OPA301(or OPA302): Use for the low impedance circuit
--- Feedback-Resistor is less than 1000 ohm
--- Headphone-Amp output circuit (only if the supply voltage is ± 5V or less)
--- However, due to high Supply Current (Quiescent Current), depending on the product, you need to check it even if the Supply Voltage is reduced.
2. OPA2301(or OPA2302): Use for a high impedance circuit
--- Feedback-Resistor is more than 1000 ohm
--- However, the Supply Current (Quiescent Current) is low.
3. If you do not know the value of the Feedback-Resistor or uncertain, the two, it is recommended that you choose to try the actual use.
Feedback Resistor is:
Resistor connected between the Negative Input and Out in opamp circuit.
Found the cause for oscillation. When the ADC works in clipping it began to swing. (I think my english is terrible).
Regards
Dieter
SMPS vs Linear
Do note that one is not inherently better than the other. There are good and poor examples of both types. The difficulties associated with making a good SMPS are a bit more challenging than those for linear. As with anything, if the designer is not thorough in the design process the result will be less than what is possible. That, plus the potential of using the PSU for applications that were not considered in the design phase determines the ultimate perceived quality of the product.
Also, most SMPSs have linear circuitry as the final regulating stage of one or more of their outputs.
Do note that one is not inherently better than the other. There are good and poor examples of both types. The difficulties associated with making a good SMPS are a bit more challenging than those for linear. As with anything, if the designer is not thorough in the design process the result will be less than what is possible. That, plus the potential of using the PSU for applications that were not considered in the design phase determines the ultimate perceived quality of the product.
Also, most SMPSs have linear circuitry as the final regulating stage of one or more of their outputs.