Connecting DAC to a tube phono preamp

Hi, I recently acquired a tube phono preamp and I don't want to use it just for my turntable but also for my digital sources. As far as I know, I can achieve this by feeding the signal from DAC through a reverse riaa circuit (R-riaa) to the preamp. My problem is where should I add the voltage divider? Basically there is two options, adding between the DAC and R-riaa or between the R-riaa and the preamp.

In addition, although I can find somewhere to purchase the R-riaa, I can't find anywhere sell the voltage divider and I assume I have to make one by myself. My demand for the voltage divider is simply the following. First, it is able to reduce 2V from line stage to 200mV so that it doesn't overload my preamp. Second, I prefer it to have rca input and 3.5mm rca input jacks. In this case, what material do I need? I haven't diy before but this seems to be a easy project.

By the way, does anyone have the experience of doing similar thing, what is your impression about the result and what suggestions you would have for me?
 
I can't find anywhere sell the voltage divider and I assume I have to make one by myself.

https://hifisonix.com/shop/hifisonix-accurate-inverse-riaa-network-irn/

But simple anti-riaa is just a few resistors +capacitors, you can DIY..

By the way, does anyone have the experience of doing similar thing, what is your impression
Did this for the measurement purposes.
But listening the DAC in this condition is not good.

and what suggestions you would have for me?
Not to do this, if you want to listen the music :)
 
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https://hifisonix.com/shop/hifisonix-accurate-inverse-riaa-network-irn/

But simple anti-riaa is just a few resistors +capacitors, you can DIY..


Did this for the measurement purposes.
But listening the DAC in this condition is not good.


Not to do this, if you want to listen the music :)
It is for listening unfortunately😂. I just can't refuse the tube amp for the price which also has a decent build quality, and is in fact even cheaper than diy one by buying the kit. I know this idea of connecting the DAC to a phono preamp is not popular, but I listen digital more than vinyl so this thought comes in my head.
 
You have not said what DAC you want to use, but chances are very good that your DAC puts out enough voltage that you could drive your amp directly from the DAC.
I've done this for years very successfully, my "preamp" is a high quality dual potentiometer as volume control and switches for source selection. AKA Passive Preamp.
Don't molest the the poor phono pre, leave it as it is and enjoy playing records with it. Use it as one input source to a passive preamp and the DAC as another.
Simple and sounds great. There are lots of examples on the Web as to how to do this.
 
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Doing this is a pretty good recipe for a substantial reduction in sound quality - if digital is your preferred listening medium you logically would want to optimize the performance with your primary digital source. You haven't said anything about your amplifier/pre-amplifier/integrated amp - worst case you can purchase an inexpensive source switch box and connect to input on your amp and connect your DAC and phono pre to the inputs on the switch box.
 
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Sorry about the lack of information. So I have a smsl m300se DAC, and I am looking for the musical paradise mp-p1 phono preamp. This unit is sold for 340CAD for used in my local store and the tube were checked by technician before sell. There are two pairs of 12ax7 tubes and they are interchangeable with 12at7 according to the manufacturer. I don't have the circuit diagram of the preamp as this is not included in their website. Thank you for many of you guys help. BTW, the reverse riaa circuit I am looking for is from six acoustic. However, since some of you say I can bypass the riaa circuit and this idea sounds better than my original one so I may not need the riaa anymore.
 
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Hi guys. After considering it for a while and received the message that the manufacturer won't provide the schematic. I think it is better for me to use it as it is that means for the phono only. Since part of my purpose is to implement tubes on my digital sources in an inexpensive way, I will open another thread to ask for advice about different designs of Nutube preamp/buffer. However. in the meantime, if any of you want to give me more insight into this issue, feel free to post it, I will read it and give it my honest thought.
 
You don't need a buffer between the output from your DAC and the input of your integrated amp. But...

If you want to investigate 'tube sound' then I say "Why not?" Do it.

I would say try building a simple and proven project like Salas' 6V6-triode preamp design. He designed one version with adjustable gain, and another version that's a cathode follower with 1X (0dB or 'unity') gain.

https://www.diyaudio.com/community/threads/6v6-line-preamp.102352/