I would use rephase rePhase download | SourceForge.net it has a lot of options for phase manipulation and is free, there is a very log thread about it on the forum rePhase, a loudspeaker phase linearization, EQ and FIR filtering tool
edit:too slow
I use rephase on my macbook by using virtualbox and a version of windows xp, works great.
edit:too slow
I use rephase on my macbook by using virtualbox and a version of windows xp, works great.
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I’ve played with both REPhase and FIR Designer. My problem is not that my system sounds poorly. In fact it sounds very good, so I’m looking to extract that last bit of performance from it. In order to do so, I believe I need to have way more than a passing knowledge of filter design. Every time I’ve added filters (including Dirac) it’s actually sounded worse. Measurements haven’t shown much improvement either.
Clearly I need to educate myself more on this stuff
Clearly I need to educate myself more on this stuff
This might not be the best place to discuss this but, the overall target you are aiming for is very important, subtle changes to that can make a big difference, try using broad shelving EQ while listening and change it to make things sound better, measure before and after to see what difference it made. That will help you to narrow in on your preferred target, not everyone likes the same. A 1db per octave fall from 20 Hz to 20 Khz is a good place to start with an in room measurement.
If it sounds much worse after adding room correction filters they are probably overcorrecting for things that should be left alone.
Phase changes are much more subtle in difference than magnitude changes.
Physical positioning is important too, REQ Wizard has a room simulator and it does a pretty good job of showing you what is going on in the modal region, moving the speakers virtually until you get the smoothest bass response gives you a good place to try and place them and adjust from there, assuming you have a rectangular room.
If it sounds much worse after adding room correction filters they are probably overcorrecting for things that should be left alone.
Phase changes are much more subtle in difference than magnitude changes.
Physical positioning is important too, REQ Wizard has a room simulator and it does a pretty good job of showing you what is going on in the modal region, moving the speakers virtually until you get the smoothest bass response gives you a good place to try and place them and adjust from there, assuming you have a rectangular room.
Less is often more. This is why some HiFi guys want nothing in the signal path.
There is a problem with dsp correction that you not only eq the speakers but also the music that you are playing. So if you make it sond good on meny recordings then you have just made a good compromise.
I have tryed to find a way to alter the dsp settings on a album level. The ide is to use Najda dsp to eq the speakers. Then I use jRiver dsp to eq the album.
jRiver cand read album tags to switch zone. Each zone can have different dsp setup.
I’m not able to eq each album differently but I can make say 10 zones and do eq sounds that I use for old recording, good recordings and so on.
jRiver is not free but I have used it for some time and it has far more featres than you can imaging. The dsp features are quit extensive so it is probobly up yo your prosessor what you can do. So if you need more taps just buy a new pc.
There is a problem with dsp correction that you not only eq the speakers but also the music that you are playing. So if you make it sond good on meny recordings then you have just made a good compromise.
I have tryed to find a way to alter the dsp settings on a album level. The ide is to use Najda dsp to eq the speakers. Then I use jRiver dsp to eq the album.
jRiver cand read album tags to switch zone. Each zone can have different dsp setup.
I’m not able to eq each album differently but I can make say 10 zones and do eq sounds that I use for old recording, good recordings and so on.
jRiver is not free but I have used it for some time and it has far more featres than you can imaging. The dsp features are quit extensive so it is probobly up yo your prosessor what you can do. So if you need more taps just buy a new pc.
That was true, to some extent (but not always - less feedback is usually not better) in the old analog world, but less so in the digital domain.
You can EQ the speakers for their shortcomings (and those of the room). That is different from EQing for shortcomings of specific music - where you actually override the preferences of the artist/producer/engineer with your own preferences.
Hi JLOP,
The architecture of the DAC is as follows:
Ian Mc FIFO -> Ian McDualXO -> 3*DIYINHK AK4490 DAC -> Output transformer Jensen JT-11-DM
The volume control and AK4490 configuration is done by an arduino nano + oled display + rotate encoder + IR remote.
I will use dimdim ArDAM1021 Lite Project PCB to manage all this.
nounouchet
Hi Fluid,
I think you're right on all the lines.
Indeed I had been surprised by the performances of the output stages of the Najda.
I had tried to use Rephase but the manual settings are complex and you have to spend a lot of time on it.
I told myself that by using Acourate I would simplify my task and that I also have the assurance of a quality end result.
nounouchet
Rephase takes some time to get familiar with but once you get the hang of it is very powerful and easy enough to use. Acourate is good and will no doubt be easier, but getting the best result takes time with any system, testing, refining working out what you like. There is no magic button to push no matter what you pay, you still have to tell it what you want to get the right result 
The only advantages FIR crossovers have is in using more esoteric slopes and/or being linear phase. The phase can be made linear afterwards easily enough with an overall stereo FIR filter and most drivers can be crossed over well enough with standard IIR slopes and parametric EQ and delay.
The only advantages FIR crossovers have is in using more esoteric slopes and/or being linear phase. The phase can be made linear afterwards easily enough with an overall stereo FIR filter and most drivers can be crossed over well enough with standard IIR slopes and parametric EQ and delay.
IIR filters can work very well, and achieve end results very close to FIR, but it can be more labour intensive to get the same end-performance.
Nothing wrong with IIR, it's all in the implementation. It can be beneficial to use the measured driver response in a crossover design software to simulate end results. You get very far with IIR filters alone, get EQ and delay tweaked 100% and it can be hard to differentiate between a good IIR vs. a good FIR setup.
Nothing wrong with IIR, it's all in the implementation. It can be beneficial to use the measured driver response in a crossover design software to simulate end results. You get very far with IIR filters alone, get EQ and delay tweaked 100% and it can be hard to differentiate between a good IIR vs. a good FIR setup.
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Heyho,
so I have got my Najda running for quite a while now, everything is good however my volume control is mixed up (turning left to increase, turning right to lower the volume).
I am pretty sure it is just a mixup of the GPIO pins - can someone please can confirm that all I have to do is switch connection of 12 and 14 on the Expansion Port 1 pinning.
Side note: I am running Najda via I2S from an Odroid C1+ (NAS, USB HDD, and Tidal HiFi) on RuneAudio. Quite happy with my Setup.
Thank you very much! Kind regards, Alex
so I have got my Najda running for quite a while now, everything is good however my volume control is mixed up (turning left to increase, turning right to lower the volume).
I am pretty sure it is just a mixup of the GPIO pins - can someone please can confirm that all I have to do is switch connection of 12 and 14 on the Expansion Port 1 pinning.
Side note: I am running Najda via I2S from an Odroid C1+ (NAS, USB HDD, and Tidal HiFi) on RuneAudio. Quite happy with my Setup.
Thank you very much! Kind regards, Alex
I've built Najda pre volume knob and one with the Vol knob.
I didn't have the volume control switch around problem you have though. I'm afraid I can't help, it was all smooth sailing. I'm interesting in your Odroid C1+ (NAS, USB HDD, and Tidal HiFi) on RuneAudio, running I2S into Najda though.
I use USB from laptop (Lenovo with boggo HDD) to WaveIO to give I2S into Najda.
Worked well for years.. I was listening to a RPi / Digione into the S/Pdif Najda input, using Spotify 320Kb. It essentially sounded as good as my Laptop Flac solution! A RPi could go straight into Najda's I2S, I read it's been done, but few other details.. If I wanted an upgrade over the basic laptop your set up could be one route..What advantages would the Odroid C1+ have I've a RPi?
Is yours all built into your Najda box? What power supply. Are you using a SSD HDD?
I didn't have the volume control switch around problem you have though. I'm afraid I can't help, it was all smooth sailing. I'm interesting in your Odroid C1+ (NAS, USB HDD, and Tidal HiFi) on RuneAudio, running I2S into Najda though.
I use USB from laptop (Lenovo with boggo HDD) to WaveIO to give I2S into Najda.
Worked well for years.. I was listening to a RPi / Digione into the S/Pdif Najda input, using Spotify 320Kb. It essentially sounded as good as my Laptop Flac solution! A RPi could go straight into Najda's I2S, I read it's been done, but few other details.. If I wanted an upgrade over the basic laptop your set up could be one route..What advantages would the Odroid C1+ have I've a RPi?
Is yours all built into your Najda box? What power supply. Are you using a SSD HDD?
I managed to bugger my Nadja board yesterday (how? Don't ask).
I'm gutted after all these years of valiant service it's given.
A fiddle / upgrade too far...
Nick is as ever super helpful and I might have to buy a new one, we'll see.
In the meantime, anyone got a spare board or one they are not using anymore they'd like to sell?
I'm gutted after all these years of valiant service it's given.
A fiddle / upgrade too far...
Nick is as ever super helpful and I might have to buy a new one, we'll see.
In the meantime, anyone got a spare board or one they are not using anymore they'd like to sell?
Hi I built a +-12Volt ssr03 super regulator that I intend to use with my new Najda V1.3 board. However the regulator measures +-12.9 V on the outputs. So I wondering if that's ok to use or should I try to get the voltage down to 12.0V.
The regulator cant be adjusted, so then I have to figure out what components that has to be changed.
The regulator cant be adjusted, so then I have to figure out what components that has to be changed.
Thx Paul
I'm going to try Nick's bypass advice first and see if I can breath life into the board but at this point I'm not too hopeful..
But we'll see.
I've got tunes though as I have some Sonos Ones in stereo pairs around the house. Not quite up there with my 'system' though
Thanks! I'll try with that then.Hi kjb,
I think, 12,9 V should be ok.
VG, Rainair