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Output transformers for DACs

bisesik,

For the newly designed PCB, can you draw a picture similar to the one below for beginners?

messageImage_1594105018347.jpg
 
Rows in 2x5 headers are connected in parallel (just for better header fixation on the board). All the other jumpers are pre-installed for correct functioning.
Regarding terminals. I suppose it is possible to use terminals instead of XLRs\RCAs using existing thruhole pads, somehow this way:

Buffalo_terminals.jpg

term_correction.jpg

based on that terminals:
Blocked

But definitely it is possible to correct PCB for regular terminals at require in the next orders (will take extra time of course for manufacturing).
 
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Joined 2008
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I am working on a TDA1541A DAC based on Ryan’s D3 boards.

The first version is a single D3/TDA1541A. I will simply be trying it with a iv resistor to see how it works with my system. However, I’ve already put things in motion to try dual/mono TDA1541A in the future.

Ryan already purchased a set of your transformers for use with his boards and gave a good review.

If I want/need a pair of your iv transformers...do they have to be wound specifically for either a single TDA1541A or the dual/mono?...or is it possible to use the same transformers with either arrangement?

Also, can you post the dimensions of your current PCB for the transformers so I can make sure I have space allotted in my case?
 
chromenuts, Myint67
There is a problem with TDA1541 in original SE connection mode is caused by the DC-offset presented at the output. I can make suitable transformer in general, but the special type of the core is needed then, which I haven't now (and do not want to order a batch due to low demand compared to other non-DC-offsetted DACs). There is another way to solve the offset, to make the additional compensation coil. First, it is more expensive to manufacture, but it is more complicated for the end user in addition as the separate power source will be needed.
Taking into account all aboved, I prefer to avoid DC-offsetted DACs. But the differential mode of 1541' connection allows to use my transformers in a regular way - all you need is just to use center tap at GND (two primary coils) - two DC-offsets should be selfcompensated then and cores will not be oversaturated.

Lets wait for Ryan's report (transformers are still on the way to him)...
 
chrome nuts, Myint 67...
Thanks to your posts, I have renewed my "investigation" on the TDA1541A (which is inside my Marantz CD65 CDP), which was paused during the last 2 years many times in attempts to find the needed approach of winding. As a result just today I have found the way to make transformers, suitable for TDA1541 in SE mode without need of DC-compensation.
FR 20-20k: -0.3 / -0.8 dB (1.8Vp-p)
 
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9038 pro

dear Ivan,
transformer (attach) can use 9028 & 9038 pro dac ?
one of diy munber selling transformer for ian pcb (9028)
i would like to use quan hao pro dac & your IV out put pcb board.

best regards
myint
 

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Hi bisesik

I do not have the experience to understand or implement differential mode. If it entails a balanced output arrangement, then that is not what I am after. I need a single ended output as you mentioned.

I was under the impression I could still maintain SE output while implementing a dual mono configuration by using a second D3 board and TDA1541A.

I thought Ryan already had a set of your transformers. I guess I misunderstood and he had simply tried another type of transformer IV stage and had ordered a set of transformers from you.

Ryan designed his D3 boards with a IV resistor and DC offset compensation circuitry to null the offset on board. I was hoping that meant the DC offset issue was irrelevant.

Please excuse my ignorance regarding these issues.

I would be interested in any transformer IV stage solution you were able to come up with that would allow me to avoid further complexity in this first DAC build of mine.
 
chromenuts,
Differential mode of any DAC connection relates to its performance, DC-offset cancellation in case of TDA1541 is a bonus. Balanced or SE output is a part of the secondary coils and independent from DAC connection mode. In any case as I wrote, I can offer two versions (or one versatile) for regular or for differential mode of TDA1541 connection.
 
time to tell how the bisesik trafo play

my dac is JLsound AK4493,,with clock board and usb input

i have used 3 different output board

JLsound output board with Newclassd discrete opamp---absolute not bad

Mirand discrete output board---a little bit better

and now bisesik output trafo---by far the best

sound from the trafo..strong, dynamic,open,,nice for the ear,,lovely sound

i use the muting from JLsound output board,,so i have no click from the dac

well done bisesik
Best Bjarne