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Wich pre-phono USB?

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Hi everyone.

I am looking for a USB phono preamplifier (MM/MMC) to improve the performance of my AT-LP5X turntable, to be used only with HIFIMAN HE1000 headphones. I'm focusing on the Topping A30pro and Topping A70pro headphone amplifiers. My DAC is smsl DO300 (in my opinion it's good).

What pre-phono can I choose in balance with my previous choices?
 

somebodyelse

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From what you've described I can't see where USB comes into this. Wouldn't you just use the phono outputs from the AT-LP5X into the phono preamp, and take analog outputs from the phono preamp to the headphone amp? I haven't seen any measurements of the phono stage in the AT-LP5X so it's hard to say what would actually be an upgrade.
 
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From what you've described I can't see where USB comes into this. Wouldn't you just use the phono outputs from the AT-LP5X into the phono preamp, and take analog outputs from the phono preamp to the headphone amp? I haven't seen any measurements of the phono stage in the AT-LP5X so it's hard to say what would actually be an upgrade.
  • The AT-LP5X has a USB output for digital conversion.
  • It can be used through the integrated pre-phono in the turntable, although the quality of the built-in pre-phono is poor.
  • If I'm considering a new pre-phono, it’s advisable to choose one that is MM/MC compatible and has a USB output.
 

Rja4000

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  • The AT-LP5X has a USB output for digital conversion.
  • It can be used through the integrated pre-phono in the turntable, although the quality of the built-in pre-phono is poor.
  • If I'm considering a new pre-phono, it’s advisable to choose one that is MM/MC compatible and has a USB output.
I don't think so.
If you want to bypass the phono preamp integrated in the turntable, a fortiori you want to also bypass its ADC to USB.

I don't know if you'd get any benefit from swapping phono preamp.
But if you want to go that way anyway, pick any of the (unbalanced inputs) phono preamps recommended by Amir.
And forget about USB.

1000018620.jpg
 

somebodyelse

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There aren't many phono preamps with USB output, so it seems like an unnecessary restriction when you could connect the output of an analog phono preamp to a separate usb audio interface if you needed to do any conversion. You can check out the phono preamps in the review index, but I think the only recommended one with USB is the Pro-Ject Phono Box DS2 USB which seems over the top for that turntable, assuming you can still find it anywhere. Do you have a link to measurements showing how bad the integrated phono pre is, or is it just hearsay?
 
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Do you have a link to measurements showing how bad the integrated phono pre is, or is it just hearsay?
I don’t believe that specific measurements are necessary to establish that an integrated preamp in a $300 turntable can be better or equal to a specialized preamp that costs the same amount on its own... Thorens MM-008 ADC, maybe is one solution
 

DVDdoug

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although the quality of the built-in pre-phono is poor.
What's wrong with it?

A different cartridge will probably make a bigger difference. But its mostly frequency response which can be tweaked with EQ or bass & treble controls.

Of course the weakest link is usually the vinyl itself and some records sound better than others.
 

MaxwellsEq

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I am not discussing the listening experience of vinyl records and the entire audio chain starting from the cartridge. Instead, I am trying to determine the best solution for converting vinyl records to FLAC files. It seems that I should use the line output of my turntable, which has certainly been preamplified by a very basic circuit, correct?
There are two approaches (assuming you don't like the built in device.

1) use a phono preamplifier you like (I use a Cambridge Duo) and feed it into an ADC (I use an RME ADI-2 Pro) plugged into a computer to write the FLAC. The results I get are great.

2) use a dedicated device such as the Waxwing or the newer ADI 2/4. Both can do RIAA in the digital domain and feed their outputs into a computer to write the FLAC
 
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Some advised against replacing the AT-VM95E cartridge with the AT-VM740ML, claiming that I wouldn't notice significant differences. I took the trouble to conduct measurements with DELTAWAVE, using AUDACITY and the same track from a practically untouched vinyl. I connected the AT-LP5X turntable's USB output to a computer's audio input to verify if it was just my imagination. Then, I manually aligned (sample level) the two tracks and processed them with DELTAWAVE. I am attaching some results of the comparison.

The natural question is as follows: If, as recommended by all online guides, I had used the phono output of the LP5X and sent it to a phono preamp of higher quality than the one integrated into the turntable, would I have recorded more significant differences? Or are they just suggestions? Normally, I don't let myself be influenced and proceed with measurements as much as possible.

In blue, the results of the AT-VM740ML cartridge ( first image ). In the second image just the differences of two wave
 

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OP
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Probably there is a fundamental misunderstanding, certainly generated by the way I have argued, and for this, I apologize. Reading other discussions on this forum related to vinyl ripping, I came across the discovery of an audio interface called Waxwing by Parks Audio.

Ripping, in my case, has little to do with the storage and musical usability of the disc itself, but almost predominantly for taking measurements, as I showed in the previous post. I am a strong advocate that vinyl has too many disadvantages to seriously compete with 16/44.1 audio, and I am somewhat disappointed that even the physical CD support has lost interest in favor of the digital, even lossless, format.

In my opinion, 90% of the significant audio quality (that which is appreciated by our ears) of a turntable depends on the cartridge and its setup. Then it all depends on how we treat the outgoing signal, which is normally not only not pre-amplified but also has an electrical output level significantly lower than any other audio source.

Therefore, if I were to add a phono amp to my turntable, it wouldn't be a wrong thing, especially since in any case, the signal to my speakers comes from the phono stage (which has some problems as it occasionally mutes for a fraction of a second) of my integrated amplifier, which is over 20 years old. Additionally, I would enter it using my SMSL DO300 DAC, which has a quality threshold certified by hundreds of measurements that I also find around here.

The question to ask, then, is whether the chain: TT phono out > new Phono Amp - USB > Computer

is preferable to the original chain: TT USB > Computer (use integrate pre-phono amp)

From all sides, I read that the first one is better, especially considering that in any case, my complete audio chain would be:
TT phono out > new Phono Amp > DAC > Amplifier > Loudspeakers

because the phono stage of my amplifier is in bad shape.

As I specified, I don't follow trends or hearsay, but I trust measurements, and I haven't found measurements around certifying that I would be wasting money with the second solution.

Thanks
 

MaxwellsEq

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TT phono out > new Phono Amp > DAC > Amplifier > Loudspeakers
That's not quite right. You need an ADC in the chain. You can never feed an analogue signal into a DAC. A DAC is a Digital to Analogue Converter, not the other way round, i.e. an Analogue to Digital Converter (ADC). DACs are everywhere, in standalone boxes, phones, dongles, computers etc. Standalone ADCs are much, much less common (although every cellphone has an ADC to convert voice to digital). Most standalone ADCs are purchased by people buying a USB interface such as a Scarlett for recording guitars, voice etc.
is preferable to the original chain: TT USB > Computer (use integrate pre-phono amp)
Well none of us can know for sure without measurements. But it's generally received wisdom that cheap built-in phono preamplifiers with USB outputs measure less well (and are much less flexible) than either a Waxwing/Puffin or a good quality phono preamplifier fed into a quality ADC.
 

Rja4000

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The Thorens MM-008 ADC is ADC as the USB prephono amp in the same range.
Maybe, but I doubt you could feed a DAC with its USB output. (Are you able to feed your DAC from your turntable's USB output ?)

And what would be the benefit to add an ADC + DAC between your analog cartridge and your analog integrated amp ?

You just use the (new) analog phono preamp's output to feed the amp. That's it.

If you find a new phono preamp which also has an USB output, you can send to your PC, indeed.

But you could as well use another ADC to USB attached to your amp's "record" output, as if it was any recorder.
There are plenty of line level ADCs on the market, even second hand, that could do that with good results. It will be much easier to find a good analog phono preamp and a decent line level ADC than to try and combine both in the same box. And a line level ADC will have more use than just the phono input.

Ultimately, you may want to sale your DAC and save on purchasing all this and the headphones amp you plan and go for the state-of-the-art (but expensive) RME ADI-2/4 Pro SE I measured here. It will do all this for you and more, and better.
But that's pushing to another level.
 
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