Hehe my praisal cannot do your work justice.
So anti imaging+ droop it is. Does it matter which comes first? And i probably shouldnt lose any sleep over this bur how much of dynamic is affected by all those inductors in place?
Ill be building your 4 inductor filter after the iv, then buffer after the filter. I cant wait for the sound !
So anti imaging+ droop it is. Does it matter which comes first? And i probably shouldnt lose any sleep over this bur how much of dynamic is affected by all those inductors in place?
Ill be building your 4 inductor filter after the iv, then buffer after the filter. I cant wait for the sound !
These days I have settled for the 3 inductor version (with the resonant caps to make the filter quasi-elliptic) - the droop filter I include right at the end, after the output buffer to reduce any ultrasonic noise contribution from that buffer.
Adding the inductors for anti-imaging filtering made a substantial difference to the dynamics (I first tried it out on the 'LAID' parallel DAC using about 19 TDA1387s) and it was the first example I got of a 'holographic' kind of soundstage.
Adding the inductors for anti-imaging filtering made a substantial difference to the dynamics (I first tried it out on the 'LAID' parallel DAC using about 19 TDA1387s) and it was the first example I got of a 'holographic' kind of soundstage.
Ah, so is it
I/v>anti imaging>buffer>nos droop in your case? I shall try that, then.
I dont remember seeing a 3 inductor version on your blog, but it is a lot of posts to study thru... if its not there may.i ask for.the schematic?
So contrary to my assumption the dynamic actually increases with anti image filter?
How is it so? Simply because.theres.more 'signal' and less.junk?
I/v>anti imaging>buffer>nos droop in your case? I shall try that, then.
I dont remember seeing a 3 inductor version on your blog, but it is a lot of posts to study thru... if its not there may.i ask for.the schematic?
So contrary to my assumption the dynamic actually increases with anti image filter?
How is it so? Simply because.theres.more 'signal' and less.junk?
Here's a version of the anti-imaging filter where I reduced all the different capacitor values down to just two : http://www.diyaudio.com/forums/digi...ign-mod-not-play-music-not-6.html#post4460683
Yes you got it - above the Nyquist frequency the DAC's still putting out junk which intermodulates with audio band signal, and with itself to reduce dynamics. If you don't filter this it creates noise modulation in downstream circuits.
Yes you got it - above the Nyquist frequency the DAC's still putting out junk which intermodulates with audio band signal, and with itself to reduce dynamics. If you don't filter this it creates noise modulation in downstream circuits.
Richard you are my hero, haha. Your nos droop filter sounds awesome. I dont think i can live without it from now on. Its hard to be subjective knowing what it does but if i didnt know its effect id say treble became fuller, whole music more vivid and smoother. I put it after the buffer as you suggested and not only does it correct the droop but it seems to have an extra filtering effect. Lpf aside, how much of an effect does the inductor have in the overall sound and do you think ill find much benefit going from the green thing in the pic to fastron or else you may recommend?
Aside from the jfet boz buffer, everything is inspired from your stuff, from the choice of 1387 over others, 6v psu (i dare not take it up to 8v tho i want to. Ill have a field day unsoldering smd if it burns...) your iv, jfet boz, then your droop filter. This already sounds miles better than some 1k dollars dacs that.i had. Unmatched dynamics.and resolution. And that sweet nos silkiness. Thank you richard!!!
I.think ill go for your 4 inductor filter, btw, if isnt degradation to the version you linked me. Simply because there would.be less.soldering and fussing over.connections involved. 3 inductor version seem.more.complicated....
Aside from the jfet boz buffer, everything is inspired from your stuff, from the choice of 1387 over others, 6v psu (i dare not take it up to 8v tho i want to. Ill have a field day unsoldering smd if it burns...) your iv, jfet boz, then your droop filter. This already sounds miles better than some 1k dollars dacs that.i had. Unmatched dynamics.and resolution. And that sweet nos silkiness. Thank you richard!!!
I.think ill go for your 4 inductor filter, btw, if isnt degradation to the version you linked me. Simply because there would.be less.soldering and fussing over.connections involved. 3 inductor version seem.more.complicated....
The droop filter does do some filtering so your ears aren't deceiving you, just its fairly gentle. If you like the extra filtering it provides, the anti-imaging filter will give you a whole lot more. Of course the effect depends on what's downstream in your system.
What's the 'green thing in the pic' ? If you are using one of those small green inductors (like I found in my CD players in the 1980s) its almost certainly not 10mH.
Its great to get your feedback - being able to get much better sound than expensive commercial products on a small budget is the essence of what DIYAudio is about for me.
If you want a version of the filter with fewer caps, look at the schematics matt_garman posted earlier in that thread. But with fewer caps you have more different values to buy so it gets more expensive in parts at Mouser's pricing.
What's the 'green thing in the pic' ? If you are using one of those small green inductors (like I found in my CD players in the 1980s) its almost certainly not 10mH.
Its great to get your feedback - being able to get much better sound than expensive commercial products on a small budget is the essence of what DIYAudio is about for me.
If you want a version of the filter with fewer caps, look at the schematics matt_garman posted earlier in that thread. But with fewer caps you have more different values to buy so it gets more expensive in parts at Mouser's pricing.
Hi richard, the inductors were these guys- 28.5ohm dcr each. At least they were matched. XD
https://www.google.co.kr/search?q=green+inductor&newwindow=1&client=ms-android-kt-kr&prmd=ivn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwimsfPJ1ebLAhULJpQKHTYrA3sQ_AUIBygB&biw=360&bih=559#imgrc=A6-JIUsWo2lj8M%3A
Would torodial cores be better alternatives if size.isnt concern? Theyd actually be cheaper here for me than smt types.
Ill check out matt's posting, but for now my.concern is finding the right inductors. Of course your blog is being a tremedous help.
https://www.google.co.kr/search?q=green+inductor&newwindow=1&client=ms-android-kt-kr&prmd=ivn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwimsfPJ1ebLAhULJpQKHTYrA3sQ_AUIBygB&biw=360&bih=559#imgrc=A6-JIUsWo2lj8M%3A
Would torodial cores be better alternatives if size.isnt concern? Theyd actually be cheaper here for me than smt types.
Ill check out matt's posting, but for now my.concern is finding the right inductors. Of course your blog is being a tremedous help.
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Google link doesn't work for me as Google's blocked here.
With 28.5ohm DCR they will have rather low Q - meaning they're too lossy. That will translate to introducing more droop in the filter. Maybe you could tweak the output filter to compensate for that. I chose the MSS1210 from Coilcraft because of its low loss, just 7ohms DCR.
If finding appropriate inductors is too difficult, you can always try out my newest DAC filter design which doesn't use inductors. Its an active filter - many many more parts than the inductor-based one but they're all cheap and relatively easy to find.
Toroidal cores for inductors? I've not seen suitable ones - got a link?
With 28.5ohm DCR they will have rather low Q - meaning they're too lossy. That will translate to introducing more droop in the filter. Maybe you could tweak the output filter to compensate for that. I chose the MSS1210 from Coilcraft because of its low loss, just 7ohms DCR.
If finding appropriate inductors is too difficult, you can always try out my newest DAC filter design which doesn't use inductors. Its an active filter - many many more parts than the inductor-based one but they're all cheap and relatively easy to find.
Toroidal cores for inductors? I've not seen suitable ones - got a link?
An externally hosted image should be here but it was not working when we last tested it.
They were these guys. Certainly sounds better with them but they add a layer of hash to.the sound; graininess. which kind of worries me if fastron will have the same effect but to a lesser degree.
Im actually looking at coilcraft series as they are much cheaper.
Still no good with smd so leaded they will have to be.. sigh..
http://www.coilcraft.com/rfb0807.cfm
Yikes no google. I uses to live in qinghao and remember how suffocating it was with censored internet. Did not even bother to try vpn as the internet was already god awful slow without it, haha..
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http://www.amazon.co.uk/Toroid-Inductor-Wound-220uH-59mOhm/dp/B00EZC5XVK
Torodial core? Im sure thats not the official term but they are these.
Torodial core? Im sure thats not the official term but they are these.
I found my magic.bullet.
Local made ferrite core inductors much like the coilcraft that i mentioned, and these are 10mh for sure (had them measured there). Excellent build quality (made in korea) and 30cents each to boot. Your filter will be made soon
Also what do u think about turning your single bjt iv into a darlington one?
Local made ferrite core inductors much like the coilcraft that i mentioned, and these are 10mh for sure (had them measured there). Excellent build quality (made in korea) and 30cents each to boot. Your filter will be made soon
Also what do u think about turning your single bjt iv into a darlington one?
I've been busy with other projects lately but now am finally ready to build the dac of my dreams
i've been looking at yamamoto yda-01 which seem to use single transistor i/v much like yours, richard, but it's a pnp with negative supply.
what do you think is the advantage with such a setup?
looking at the pic of their output board it looks like a vanilla monolithic regulator (very possibly lm338) then to to-92 single transistor i/v for both +/-, combined with can type tr buffer output (perhaps triangular buffer?)
and knowing how your npn i/v sounds already, i'd imagine the yamamoto to have excellent clarity combined with muddy, plump bass thanks to the impedance issue of what i speculate to be lm338 regulator. all speculation, of course.
but this dac seem simple enough to emulate with promising results.
i've been looking at yamamoto yda-01 which seem to use single transistor i/v much like yours, richard, but it's a pnp with negative supply.
what do you think is the advantage with such a setup?
looking at the pic of their output board it looks like a vanilla monolithic regulator (very possibly lm338) then to to-92 single transistor i/v for both +/-, combined with can type tr buffer output (perhaps triangular buffer?)
and knowing how your npn i/v sounds already, i'd imagine the yamamoto to have excellent clarity combined with muddy, plump bass thanks to the impedance issue of what i speculate to be lm338 regulator. all speculation, of course.
but this dac seem simple enough to emulate with promising results.
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