This one is very similar to mine (please see pictures) : the only difference is that I have a direct bass output with a variable frequency split.
Using my Magical Box and a modified balanced headphone, of course, it is very close to the FX-802, but the V200 sounds a bit better than both 326, of course IMHO, as reported in my post.
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Yes if you want to do it Abraxalito's way and don't live in China. I use FDA without output transformers simply connected to speakers as intended. No more audiorack needed as it is almost empty.
I have the transformers in stock but never used them on any FDA. They are not free and they will bring costs up to a level. When connecting speakers FDA is an affordable road to good sound but it is not ideal. Nothing is really.
I have tried quite a few and stayed with a Wadia but the Alientek D8 is tempting. It has an analog headphone amplifier thus making the transformers unnecessary if you are not too critical and listen to loudspeakers mostly. It all depends but I don't even have headphones. Tiring experience, listening to headphones.
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@ Abraxalito :
After our discussion I derived the pad I called my "Magical Box" in my post, since it can be used in several ways either with an active system, or a balanced headphone and even both together... You can connect several headphones if needed !
Two resistors per channel define a pure 8 ohms resistive load, whit a very good attenuation (25 dB or so with 8.2//0.5 ohms), what is the best load needed for these PowerDACs. I don't think the transfos are of paramount importance here. But it's of course my personal opinion.
After our discussion I derived the pad I called my "Magical Box" in my post, since it can be used in several ways either with an active system, or a balanced headphone and even both together... You can connect several headphones if needed !
Two resistors per channel define a pure 8 ohms resistive load, whit a very good attenuation (25 dB or so with 8.2//0.5 ohms), what is the best load needed for these PowerDACs. I don't think the transfos are of paramount importance here. But it's of course my personal opinion.
The reason to reduce the power here with the PowerDACs is to use them with headphones in a balanced connection to avoid the use of a classical DAC with a headphone amplifier.
Since the PowerDACs do a very good job in digital to analog conversion without the issues of the classical DACs connected to amplifiers, and that they have plenty of power to drive loudspeakers, they also can be used with headphones/IEMs but, of course, after a substantial attenuation !
There isn't any voltage output stage in FDAs/PowerDACs then they are very silent and the signal isn't degraded as in analog amplifiers with voltage amplified output.
I have one of those too, haven't opened it up yet. From the internal pics of that on Taobao and Aliexpress, I couldn't see an additional pair of inductors for the bass output - this puzzles me.
You could probably improve the dynamics into headphones even without transformers by increasing the resistances (while keeping the same ratio). Its unlikely you'll need an output impedance below 2ohms, so you could go to 33ohms/2 ohms. Of course you'd then need to increase the output inductor values and decrease the capacitors as the damping would be too low with the stock inductors.
Thank you Abraxalito for the suggestion. The audition results, both with the active system (Genelec) and the bunch of headphones I tested, are really good and far from my expectations to be honnest. And cherry on the cake : I use all my headphones in a balanced mode. Certainly IMO, the best way to use headphones...
First the sound is not at all degraded by this resistors combination, secondly I can use headphones and actives monitors at least connected simultaneously (a good option to make instant audio comparisons...), and more importantly for me, without mind of the impedances of the devices connected to the pad. The less there are electronics between the output of the PowerDACs/FDAs and their listening, the better.
First the sound is not at all degraded by this resistors combination, secondly I can use headphones and actives monitors at least connected simultaneously (a good option to make instant audio comparisons...), and more importantly for me, without mind of the impedances of the devices connected to the pad. The less there are electronics between the output of the PowerDACs/FDAs and their listening, the better.
Are you connecting the attenuated output to your active monitors? If so, based on my experience into my amp, you'll be losing dynamics because there's still a substantial ultrasonic component at the output (the carrier wave, typically at 8fs). Once I installed a passive filter to attenuate the carrier my DAC sounded astoundingly good.
(50W+50W)STA326 OLED 2.1 digital amplifier machine (STA326 + PCM2706 + AK4113) | eBay
Hi Guys....
I bought like the above (or in ondesx photos). Does anyone know who makes and where I can get an operators manual. I have no instructions.
Can anyone give me a link to the instructions. I have only connected it one and it sounded good. The speaker posts are a little small for my wire...have to fix
Thank you
D
Hi Guys....
I bought like the above (or in ondesx photos). Does anyone know who makes and where I can get an operators manual. I have no instructions.
Can anyone give me a link to the instructions. I have only connected it one and it sounded good. The speaker posts are a little small for my wire...have to fix
Thank you
D
It looks like it also uses XL2596. Please check ripple voltage on that one. In D802 it is extremely noisy.
Yes : the outputs are connected from one side to my active monitors (the 1094A in series with the 1032A for each channel) and the other to one of my balanced headphones. I haven't noticed such a lose in dynamics neither with the active system compared to a direct connection to several DACs (the last one is the M51), nor with any of my headphones : all cans sound very good, and definitely better than with a headphone amp in single-ended version ! Anyway, I'll test your option asap.
I bought recently the SMSL SAP-9 which allows balanced connections too and the comparison remains in the favour of the PowerDACs/FDAs connected directly through the pad.
I received the TAKAS 50 (https://www.aliexpress.com/store/pr...-USB-Coaxial-Optical/1269413_32562907821.html)
This unit uses the TDA7498E (http://www.st.com/content/ccc/resou...df/jcr:content/translations/en.DM00044235.pdf)
It plays very loud and is in the same league as the V200 more or less. It becomes difficult to make a clear distinction, because these devices are very close from the audio quality point of view. This last unit will be a very good deal for people with low sensitivity loudspeakers, for sure !
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The amplifiers you mention are not FDA. They have a DAC and analog volume control. Maybe it is better to focus on FDA with STA326 (or variants) in this thread as the thread title is "Full digital amplifier with chip STA326". Diyaudio.com wishes not to make a separate subforum for FDA and therefore it is classed in "Class D" which makes it hard enough to focus on FDA subjects. There are several threads on class D amps where those can be discussed. This to avoid mist/noise as in other threads.
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I reckon that your headphones will be sounding more dynamic than your speakers as headphones don't care about being exposed to ultrasonics. You could try a capacitor at the output of the 33R/2R attenuator to give some ultrasonic attenuation. Try a 1uF film cap across the 2ohms - it won't affect the audio band but will give about 12dB attenuation at the carrier freq. Then listen to see if you gained any dynamics.
Sorry Jean-Paul, but the FX-802C and the YJHiFi both use the STA326. I admit that the V200 and the Takas A50 are using different chips and, of course, I just mentioned them because I had them in test. Anyway, I'll no more make reference to them from now.
My purpose was to use any FDAs as a combo DAC-amplifier for headphones, like Abraxalito did, but using transformers.
I've succeed with the pad and I'll make now some tests, as suggested by him, to improve these devices as DACs in an active system.
From my recent tests, I have not noticed any issue with dynamics, neither for the headphones, nor for the active system. Anyway, I'll make several tests with your suggested mods.
Thank you again for your help.
With dynamics its not like we notice any issues, until we make a change which improves them. That's an 'aha!' moment, its only then we notice what we were missing before.
An externally hosted image should be here but it was not working when we last tested it.
Link is to Taobao - Works on my phone??? Does this image show it?
Heres abother link http://m.intl.taobao.com/detail/desc.html?spm=a1z5f.7632052.0.0&id=42055429543
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