I have ordered the Belleson super regulator to replace the existing 5+ regulator in my dacmagic:
http://www.partsconnexion.com/product17638.html
Now I see there is two versions of this regularor, 0.5A and 2A. I guess I have ordered the standard version rated to 0.5A. Will this work in the dacmagic, or do I need the 2A? I know someone in this thread has made this mod, and probably can answer this question.
Other planned mod is to bypass the output caps. I already use a xlr-rca with disconnected pin 3, as previously adviced in this thread.
I have no experience in soldering etc, so I will try to find someone who can help me.
I have had the dacmacic for a week now, and I am very fond of it. It is better than my previous dac (Harmony Design DA9) in my setup.
http://www.partsconnexion.com/product17638.html
Now I see there is two versions of this regularor, 0.5A and 2A. I guess I have ordered the standard version rated to 0.5A. Will this work in the dacmagic, or do I need the 2A? I know someone in this thread has made this mod, and probably can answer this question.
Other planned mod is to bypass the output caps. I already use a xlr-rca with disconnected pin 3, as previously adviced in this thread.
I have no experience in soldering etc, so I will try to find someone who can help me.
I have had the dacmacic for a week now, and I am very fond of it. It is better than my previous dac (Harmony Design DA9) in my setup.
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i have been reading this tread since the beginning,why go through all the trouble of swapping op amps?since the wm8740 is a voltage out dac your I/V convertion is done internally.so bypass all the output opamps-use positive out from dac,left and right channel + to center pin of rca jack,negative leave floating.try nichicon kz 47uf 25-50v caps bypassed with polystyrene or polypropylene .01 to .09.xlr output direct also with coupling caps from dac to pin 2 and 3.this will improve the sound over op amps.
To do - or not do to
Very interesting!
So you say that op-amp's in the Dac Magic, is actually not necessary at all?
Do they just work as impedance matching, so that neither the Wolfson or the connected Pre-amp will be overloaded or the other way around??
Please elaborate on this, since I believe this to be kind of tricky to carry out in practice, whitout damaging anything.
But still the basic idea'r sounds logical, but I'm afraid to ruin something, whitout very good reason
Very interesting!
So you say that op-amp's in the Dac Magic, is actually not necessary at all?
Do they just work as impedance matching, so that neither the Wolfson or the connected Pre-amp will be overloaded or the other way around??
Please elaborate on this, since I believe this to be kind of tricky to carry out in practice, whitout damaging anything.
But still the basic idea'r sounds logical, but I'm afraid to ruin something, whitout very good reason
I've done the same in the Zero DAC. I used a passive LPF (LCR) to filter out the high frequency garbage and a polypropylene cap to block DC. I think it gave the best sonic result. For some reason I changed it back to active filters with AD797 and I have been to lazy to go back to passive. I wonder if there are any issues using a DAC this way since it's not very common.
The op-amps provide extra low-pass filtering in addition to what is in the DAC, balanced to unbalanced conversion, and are rather better at driving cables and pre-amps than are the DAC outputs alone.
The DAC does some low-pass filtering (via internal switched-capacitor filters I think) but the quoted SNR figures of the DAC's spec are (usually) obtained using the data-sheet specified active-filter stages, not via the DAC alone. The reason that high-spec DACs have differential outputs is that a lot of the noise (PSU-coupled and that generated from its own internal machinations) is common-mode noise which is present on the + and - outputs. A differential-input stage rejects this common-mode noise but not the music signals which are of opposite polarity to each other. Taking just the + output you are no longer removing unwanted common-mode signals.
Many people find that without an active stage the sound lacks drive and punch, but it all depends on how the next element in the chain (e.g., pre-amp) handles this signal. It will probably sound better in some aspects and worse in others and be entirely system dependent. A DAC with an active stage is a much more predictable source and will give much better specs so you will not find many commercial DAC products that do not have one.
In other words, suck it and see!
Glenn
(The Glenn who Zapfiltered his DM)
http://www.diyaudio.com/forums/digital-line-level/142184-opening-new-dacmagic-5.html#post2089099
The DAC does some low-pass filtering (via internal switched-capacitor filters I think) but the quoted SNR figures of the DAC's spec are (usually) obtained using the data-sheet specified active-filter stages, not via the DAC alone. The reason that high-spec DACs have differential outputs is that a lot of the noise (PSU-coupled and that generated from its own internal machinations) is common-mode noise which is present on the + and - outputs. A differential-input stage rejects this common-mode noise but not the music signals which are of opposite polarity to each other. Taking just the + output you are no longer removing unwanted common-mode signals.
Many people find that without an active stage the sound lacks drive and punch, but it all depends on how the next element in the chain (e.g., pre-amp) handles this signal. It will probably sound better in some aspects and worse in others and be entirely system dependent. A DAC with an active stage is a much more predictable source and will give much better specs so you will not find many commercial DAC products that do not have one.
In other words, suck it and see!
Glenn
(The Glenn who Zapfiltered his DM)
http://www.diyaudio.com/forums/digital-line-level/142184-opening-new-dacmagic-5.html#post2089099
the filtering is done in the dac,no additional filtering is needed.most of the manufactures of dac-cd players use whats recommended by the dac suppliers,check out the wolfson web on the sheet for the wm8740!if you use any additonal filtering roll off only the the frequency of 100k and higher,otherwise it will affect you highs,26pf to 50pf to ground.try it without any filtering and you will see what I mean.if you wnat balanced you have negative and positive signals coming out of the 8740 already.
There seems to be several threads here that boils down to changes in the capacitors, power supply possibilities, and op amp upgrades. In summary I did the following changes:
• LME 49720 to replace the NE5532s
• OPA1612 to replace the OP275Gs
• ELNA caps for the coupling caps
• Add a 10uf 25V tantalum capacitor on the 5v power supply (rather then changing 30 caps)
• Replace the 7805 regulator with a DEXA 70908
The op amps helped but the Dac Magic was still lacking in soundstage. Once I changed out the coupling caps and the 7805 the DAC was transformed. For the first time the wife factor used the word muddy and it was in reference to the Benchmark!! A $300 Dac Magic, with supposedly less then 5 hours of play time, and less then $80 worth of parts put a Benchmark (in use for 9 months) to shame. For listening I am using the RCA outputs.
I then put the Aura Caps in the Benchmark, see http://www.diyaudio.com/forums/digital-line-level/70412-upgrading-benchmark-dac-1-a-25.html, and instantly the Benchmark was no longer muddy. The Dac Magic has more depth of soundstage but I think this is a bit artificial (using Kris Isaak San Francisco days). And this is from a device that hade little or no soundstage.
Thanks for both the improvements. The Benchmark is back on top with more neutrality but $400 is a lot better then $1400. Something to consider.
• LME 49720 to replace the NE5532s
• OPA1612 to replace the OP275Gs
• ELNA caps for the coupling caps
• Add a 10uf 25V tantalum capacitor on the 5v power supply (rather then changing 30 caps)
• Replace the 7805 regulator with a DEXA 70908
The op amps helped but the Dac Magic was still lacking in soundstage. Once I changed out the coupling caps and the 7805 the DAC was transformed. For the first time the wife factor used the word muddy and it was in reference to the Benchmark!! A $300 Dac Magic, with supposedly less then 5 hours of play time, and less then $80 worth of parts put a Benchmark (in use for 9 months) to shame. For listening I am using the RCA outputs.
I then put the Aura Caps in the Benchmark, see http://www.diyaudio.com/forums/digital-line-level/70412-upgrading-benchmark-dac-1-a-25.html, and instantly the Benchmark was no longer muddy. The Dac Magic has more depth of soundstage but I think this is a bit artificial (using Kris Isaak San Francisco days). And this is from a device that hade little or no soundstage.
Thanks for both the improvements. The Benchmark is back on top with more neutrality but $400 is a lot better then $1400. Something to consider.
Hi, I bought a CA Azur 650 A + CA DacMagic at the weekend, I’ve got to say the improvement in sound quality from my HTPC is jaw dropping although I was playing it through my Sony STRDH810 AV before and was warned that the music quality is not great. Anyway I’m a total noob to DIY Audio, I have just started on my first CMOY amp that’s as far as I have got so far.
I bought 2 x Neutrik NA2FPMF XLR Female to RCA Phono Socket Adapters off ebay just now, as it seemed the least technical of the upgrades mentioned in the thread ( I will also order the 9v PSU as well) but I’m a little confused about how to apply the plugs. In the thread it says to short the Pin3 , does this mean open the plug and disconnect the pin ? Is the method in Mihaylov’s post the correct one ?
I bought 2 x Neutrik NA2FPMF XLR Female to RCA Phono Socket Adapters off ebay just now, as it seemed the least technical of the upgrades mentioned in the thread ( I will also order the 9v PSU as well) but I’m a little confused about how to apply the plugs. In the thread it says to short the Pin3 , does this mean open the plug and disconnect the pin ? Is the method in Mihaylov’s post the correct one ?
I’m a little confused about how to apply the plugs. In the thread it says to short the Pin3 , does this mean open the plug and disconnect the pin ? Is the method in Mihaylov’s post the correct one ?[/FONT][/B]
The advice early on in this thread is :-
Pin 1=Gnd, Pin 2= + phase, Pin 3 = - phase.
So take signal from pins 1 and 2 and leave pin 3 alone.
This is what I did and it works fine.
Yes, but make sure pin 3 is not connected to anything if you can (left open circuit).
Some cables that are designed to connect unbalanced sources to balanced amps have pin 3 shorted to ground. You do not want this.
Then compare with the standard RCA's. It sounds more open but alters the sound balance slightly so it is possible that the standard RCA sound suits your system/ears better.
You'll get exactly 2V RMS both ways so very easy to A/B if you connect up both ways for comparison.
Some cables that are designed to connect unbalanced sources to balanced amps have pin 3 shorted to ground. You do not want this.
Then compare with the standard RCA's. It sounds more open but alters the sound balance slightly so it is possible that the standard RCA sound suits your system/ears better.
You'll get exactly 2V RMS both ways so very easy to A/B if you connect up both ways for comparison.
Thanks Puffin, when you say Leave pin 3 alone you mean disconnect it ?
LOL just been answered as I was typing the reply
Right will do that and let you know what I think .. thanks again Glenn
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If you get a chance replace the coupling caps with the Elna caps and the 7805 5v regulator with the Dexa 5v regulator. Both parts can be found on partsconnexion. Niether of these parts are surface mount and the changes you are trying to make will deliver limited results as long as these bottlenecks are in place. Besides the PSU you are considering buying voids the warranty anyways.
If you get a chance replace the coupling caps with the Elna caps and the 7805 5v regulator with the Dexa 5v regulator. Both parts can be found on partsconnexion. Niether of these parts are surface mount and the changes you are trying to make will deliver limited results as long as these bottlenecks are in place. Besides the PSU you are considering buying voids the warranty anyways.
Hi I can only find 15v Dexa UWB " Series" Regulator (Positive) (78xx Series)
Is this what you meant ?
I agree with Puffin, it worked for me. It should give you the same 2V signal as the phono output but with better signal quality.
Using Mihaylov's method will give you double the signal at the phono plug i.e. about 4V, which may distort on some inputs. If you have a ground loop the - output of the Dacmagic will be shunted to ground, not good news.
Handy memo on XLR pins 123 are X=earth, L = Live (+), R = Return (-)
Using Mihaylov's method will give you double the signal at the phono plug i.e. about 4V, which may distort on some inputs. If you have a ground loop the - output of the Dacmagic will be shunted to ground, not good news.
Handy memo on XLR pins 123 are X=earth, L = Live (+), R = Return (-)
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No you need the Dexa 70908 5v regulator. The other regulators are ok. I would do the regulator over the PSU as it is the noisy part and the critical voltage to supply the DAC and opamp chips with power, the other voltage are for the positive and negative swings of the analog signal out. The PSU can still pick up noise on it's way to the DAC. I did not change out the PSU. Parts connexion has several Dexa regulators be sure and pick the right one. Also see the thread about the tantalum cap which can be purchased from digikey.
most of the dac chips today use voltage output instead of current output,so the iv convertion is done internally.the wolfson has a negative signal as well as a positive signal coming out of the dac,your balanced out is already there,just use it.for unbalanced use only the positive or + signal for your output,one for each channel.use a really good cap here,you could use a 47uf silmic II or nichicon zk,bypassed with 1-2uf polystyrene or polypropylene.no additonal low pass filtering is needed!!!!!!!go from dac output to rca jack.once you have done this you will never go back to op amps.you already have 2 volts output from the dac to drive anything.enjoy.p.s. make sure you cut the trace going to the rca jack.