The op amp section won't be too bad as it does not pull much current. However, the Digital and D/A Analog power are going to require up to 40mA each.
If you are using 9V batteries (PP3), they are normally rated at 90mA-Hr and you won't get much run time from them.
Better would be some Li-Ion or Li-p-Ion batteries for the high current sections. Two in series would be sufficient if you remove the 8V regulator, as the following post regulators are low drop type (1V minimum).
If you are using 9V batteries (PP3), they are normally rated at 90mA-Hr and you won't get much run time from them.
Better would be some Li-Ion or Li-p-Ion batteries for the high current sections. Two in series would be sufficient if you remove the 8V regulator, as the following post regulators are low drop type (1V minimum).
I've spent a couple of days reading and digesting this thread. I'm keen on building one of these AK4396 based boards and building it with Dario's mods (thanks Dario!).
However, my system tends to be slightly bass light (Audiolab 8000 pre and power amps into Castle Avon speakers - distinct and controlled bass, but I wouldn't want less than that provided by my Arcam Alpha 8).
I'd appreciate any comments on bass performance of my Logitech Squeezebox Touch into this board. The Logitech on it's own is way too bright and unrefined. Alternatively, I am looking at an Audio-GD or Beresford Caimon or a mid-fi DIY build.
Any advice on the overall quality and bass performance welcomed... Thanks in advance.
However, my system tends to be slightly bass light (Audiolab 8000 pre and power amps into Castle Avon speakers - distinct and controlled bass, but I wouldn't want less than that provided by my Arcam Alpha 8).
I'd appreciate any comments on bass performance of my Logitech Squeezebox Touch into this board. The Logitech on it's own is way too bright and unrefined. Alternatively, I am looking at an Audio-GD or Beresford Caimon or a mid-fi DIY build.
Any advice on the overall quality and bass performance welcomed... Thanks in advance.
macklij,
While I suspect bass response is most closely related to equipment choices, I'll relate some of my experience. I have never used a Squeezebox but a similar approach is feeding the DAC from a computer (even a laptop) with JRiver Media Studio. There is an option for WASAPI-Event Style output which is a direct mode that bypasses some firmware and about all software DSP hooks.
The combination of that mode and this DAC is providing the most controlled, full and musical bass response to date,for me.. I don't know what DSP options are available with the SqBx, but I wonder if that unit might be confining the signal. There is a free 30 day demo of JRiver,and if you have the equipment I would encourage giving it a try. There are night and day differences in the sound of this DAC that depend on how it is fed.
While I suspect bass response is most closely related to equipment choices, I'll relate some of my experience. I have never used a Squeezebox but a similar approach is feeding the DAC from a computer (even a laptop) with JRiver Media Studio. There is an option for WASAPI-Event Style output which is a direct mode that bypasses some firmware and about all software DSP hooks.
The combination of that mode and this DAC is providing the most controlled, full and musical bass response to date,for me.. I don't know what DSP options are available with the SqBx, but I wonder if that unit might be confining the signal. There is a free 30 day demo of JRiver,and if you have the equipment I would encourage giving it a try. There are night and day differences in the sound of this DAC that depend on how it is fed.
Out of Curiosity (killed the cat) I decided to try the switcher again. I adjusted the frequency up to 64Hz in the hope it would be a bit more efficient.
I then hooked my DAC board up to it, and ran a FFT to see how it compared to it running off mains.
As expected, there was a degradation in performance, although not as bad as I thought it would be.
Finally I added a line filter between the switcher output and the transformer input to the DAC board to try to filter the noise. It worked pretty well with readings within .1dB of line powered.
Input voltage is 12.56V at 0.573A. I can drop the input voltage to 9.1V before the DAC drops out of operation.
FFTs are 1. Switcher Powered, 2. Switcher Powered with Line Filter, and 3. Line powered.
I then hooked my DAC board up to it, and ran a FFT to see how it compared to it running off mains.
As expected, there was a degradation in performance, although not as bad as I thought it would be.
Finally I added a line filter between the switcher output and the transformer input to the DAC board to try to filter the noise. It worked pretty well with readings within .1dB of line powered.
Input voltage is 12.56V at 0.573A. I can drop the input voltage to 9.1V before the DAC drops out of operation.
FFTs are 1. Switcher Powered, 2. Switcher Powered with Line Filter, and 3. Line powered.
Attachments
to my mind cristal clear mids are the strongest point of this dac, if you need more bass you could play with R25 and R31 by replacing it with some 100-300(?)k values. The mids become more foggy and you get some kind of equalizer. Know nothing about that - oscillations, sound degradation and so on, just noticed that
Thanks BobM. All DSP options are off on the Squeezebox - even so, I just don't think it's internal DAC quality is good enough for my (mid) hi-fi. I believe the Sqeezebox Touch (SBT) is bit transparent on the digital outputs though - hence my interest in this DAC.
I may well order the parts and then compare the SBT against a demo of JRiver. Technically there should be no difference.
to my mind cristal clear mids are the strongest point of this dac, if you need more bass you could play with R25 and R31 by replacing it with some 100-300(?)k values. The mids become more foggy and you get some kind of equalizer. Know nothing about that - oscillations, sound degradation and so on, just noticed that
Thanks dtses. That's useful. The mid-range is in many ways the most important to me. Still worried about the bass though. Still tempted to build this - it wouldn't be a massive loss even if I didn't use it in the long run.
My DAC has been up and running for a few weeks now and sounding really good to my ears (tested OK at recent medical). Playing from CD through a shigaclone CD transport into a myref revC ultimate amp into Yamaha NS-10 speakers (near field listening (in the shed)).
The NS-10 are a bit weak in the bass normally but I am finding this DAC is really surprisingly good. Not missing bass punch at all though this does also depend on music preference to some extent.
I followed Dario's BOM (thanks Dario) as close as I could and I am not at all dissapointed.
BTW I love your bench picture TheGimp, nearly as untidy as mine..., curious about what material it's made of?
Couldn't understand the graphs (self-deprecation... it's a British habit).
Cheers folks
Bill
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It's a great chance to try out a bunch of different op-amps to see if there is one that gives you balance that you are after. I was quite surprised at the bass weight that came out of a lowly TL072CP, unfortunately it didn't have the clarity or soundstage of more exotic types.
Bill,
The bench is covered with 1' X 12" boards of what is called 'Particle Board'. It is a low density composite from sawdust. Unfortunately the boards are over 30 year old, and the dimensions of material today (metric) is different enough that I can not replace the front one without replacing all of them. So they remain.
The graphs are FFTs with a 1KHz tone at -7dB. The higher the peaks of the noise and harmonics, the worse it is.
With line powered transformers
THD is 0.0087%
IMD is .0001%
Modulation Distortion is 0.0003%
S/N is 86.8dB
When I powered the system with a switching power supply to generate ac from 12.6VDC, the figures went to:
THD is 0.0111%
IMD is .0002%
Modulation Distortion is 0.000%
S/N is 83.6dB
So THD got worse as did the signal to noise ratio. S/n suffered by nearly 6dB.
Adding a line filter between the ac output of the switching supply and the step down transformers brought the distortion back to what it was originally.
My conclusion was the switching supply does degrade the audio quality, but can be compensated for with a simple line filter.
The bench is covered with 1' X 12" boards of what is called 'Particle Board'. It is a low density composite from sawdust. Unfortunately the boards are over 30 year old, and the dimensions of material today (metric) is different enough that I can not replace the front one without replacing all of them. So they remain.
The graphs are FFTs with a 1KHz tone at -7dB. The higher the peaks of the noise and harmonics, the worse it is.
With line powered transformers
THD is 0.0087%
IMD is .0001%
Modulation Distortion is 0.0003%
S/N is 86.8dB
When I powered the system with a switching power supply to generate ac from 12.6VDC, the figures went to:
THD is 0.0111%
IMD is .0002%
Modulation Distortion is 0.000%
S/N is 83.6dB
So THD got worse as did the signal to noise ratio. S/n suffered by nearly 6dB.
Adding a line filter between the ac output of the switching supply and the step down transformers brought the distortion back to what it was originally.
My conclusion was the switching supply does degrade the audio quality, but can be compensated for with a simple line filter.
You're welcome, Bill
OT
We're short of Brits in the My_Ref Fremen Edition Release Candidate mini GB
http://www.diyaudio.com/forums/chip...ion-beta-build-fine-tuning-8.html#post3018487
Hi
I am awaiting the arrival of a Quad 33 pre-amp to use with my 4396 dac.
The quad needs at least 10db attenuation from the cd player output.
As the dac will be in between, is there anything I can do to attenuate the dac.
Or will I need to, don't know how the output compares to a cd player.
cheers
I am awaiting the arrival of a Quad 33 pre-amp to use with my 4396 dac.
The quad needs at least 10db attenuation from the cd player output.
As the dac will be in between, is there anything I can do to attenuate the dac.
Or will I need to, don't know how the output compares to a cd player.
cheers
your two options are (1) external attenuator, or (2) modify the DAC to operate in serial control mode using the serial interface on pins CNS (8), CCLK (10), and CDTI (11).
Serial mode will require lifting several pins, changing control settings and hooking up to a controller to talk to the AK4393.
This is a potential source of noise introduction.
Has anyone done this?
Correction, you can only add an external attenuator.
Apparently not since the AK4393 does not support volume control (AK4396 does).
Serial mode will require lifting several pins, changing control settings and hooking up to a controller to talk to the AK4393.
This is a potential source of noise introduction.
Has anyone done this?
Correction, you can only add an external attenuator.
Apparently not since the AK4393 does not support volume control (AK4396 does).
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Hi, thanks, looks like an external attenuator then.
Hi Bob, Is that a variable attenuator using a pot.
GF factor would be a no-no, I'm afraid.
Hi Bob, Is that a variable attenuator using a pot.
GF factor would be a no-no, I'm afraid.
This is the item in the picture. The only thing special about it are the staggered plates as seen in the description. Well made and inexpensive.
DACT Type 21 Stepped Attenuator / Volume 20K for PreAmp | eBay
DACT Type 21 Stepped Attenuator / Volume 20K for PreAmp | eBay
Thanks both. I've decided to build this DAC (with Dario's mods). I'll report back in a couple of weeks or so.
I run my 4396 DAC into a Quad 33 without any problem, you just don't get to use the whole range on the volume control - not a big deal.
If you haven't already rebuilt it (those electrolytics will be well dried out by now, one of mine exploded) then you may want to look at the DaDa kit. They have instructions on modifying the Quad to have a higher voltage rail for stability and also drop the overall gain to suit CD inputs.
Hi Spider,
Good to hear someone else has chosen the 33 with this dac.
It arrives Tuesday and the first thing after a quick listen, will be the DaDa kit and as you say the voltage mod. I'll buy some attenuators as well.
I have just spent a very nervous hour soldering two OPA827s to an adapter
Just plugged it in and to my surprise it works.
First impressions are extremely good, I can hear a very marked improvement even through the Marantz theatre amp I am forced to use whilst my Linn LK280 is being looked at.
Definitely worth doing.