Measurements of Parks Audio Puffin Phono Stage

[watchnerd]

Jeez man. At this point why not just play a CD!

a) I don't own any CDs. Ripped them to NAS long ago. If convenience is the ultimate goal, why play CDs? Just stream it.

b) Turntables are fun to play with, collecting vinyl is fun

c) The DSP phono stage I have (Devialet, not Puffin) preserves the character of vinyl just fine. It doesn't make LP sound like CD, so the comparison is moot.

 

[watchnerd]

If this phono stage and the miniDsp SHD got married and made a baby, it would be a killer unit - apply RIAA AND other DSP all in the digital domain and then spit out the "final" analog signal. I suppose it wont hurt too much to repeatedly go through the A-D-A path, but I'd prefer to avoid it so I don't feel dirty.

To my point earlier that you could do the RIAA in the SHD, here is someone who did RIAA in a miniDSP 2x4:

https://www.minidsp.com/forum/hometheater-av-applications/12510-2x4-hd-as-phono-preamp

 

[stunta]

It is my firm belief that when LP sounds better, it is because it is mastered differently, not because it is analog and there is some magic there that is missing in digital.

+1. This is exactly why I own LPs, a cleaner, a dedicated analog phono stage and a suspended turntable with an external power supply. There are some records that sound simply amazing on vinyl (euphonic perhaps) to my ears. I hate having to own this much gear to play them properly. I started ripping them using a Benchmark ADC but that takes some patience which I ran out of very quickly.

I am very careful with buying newer releases on LP though as a lot of times they are cut from the digital versions that are mastered poorly.

 

[watchnerd]

I started ripping them using a Benchmark ADC but that takes some patience which I ran out of very quickly.

Yeah, I find ripping vinyl in advance is a drag, not as convenient or fun as just playing on the fly. It is useful for listening to cartridge comparisons, though.

 

[patient_ot]

Absolutely true, it's really important with higher than 2.5mV rated cartridges and 'hot' modern pressings. Channel balance is also important with so much gain on tap. (That said the carts are bad at that)

BTW, which inverse RIAA are you currently using- Lipshitz/Jung (TAA 1980) or the classic Williamson (TAA 1971)?

The puffin is indeed a very interesting device.

There are "hot" pressings that go back to the 70s and 80s, maybe earlier than that. The problem I found with many phono preamps is that most designers/companies do not stress test them with higher output MM and MI cartridges. It gets complicated because some cartridges are spec'd with a particular output but in reality the output varies from example to example and can be much higher. Then you get distortion on dynamic peaks and such with a "hot" cartridge and hotly cut records (sounds like grainy distortion). The only phono preamp company I'm aware of that stress tests their stuff with very high output cartridges (up to 10MV) is Graham Slee.

If other companies aren't willing to do this they need to offer a lower gain setting (say 30-35db) rather than the fixed or lowest setting you often see around 40-45db.

 

[sergeauckland]

One further reason to need a high overload margin is because of the inevitable clicks and pops from records, especially old records. The amplitude of a click can be many dBs higher than the signal, albeit for a very short time and consequently with little energy, so may not be too intrusive. However, if the phono stage clips or even worse, latches, then what might have sounded like a click turns into a bang, and so much more intrusive.

S

 

[awkwardbydesign]

I emailed Shannon Parks as I use a Decca London Supergold cartridge, which supposedly works at it's best with a load of 22 or 33k ohms (depending on whom you ask), and the Puffin has fixed loads for MM or MC. Apparently using the Air control ,-1 or -2 will mimic those loads. Although not a fan of ADC-DAC conversion (my active crossover is analogue!) I won't cut my nose off to spite my face, so if it works, it works. I just need to try one.
BTW, I found this forum because of this review.

 

[pastorbarrett]

@amirm would be it be possible to get this on loan again to have a full set of tests? Interesting unit, seems it could be all the phono anyone might need.

 

[Dj7675]

To my point earlier that you could do the RIAA in the SHD, here is someone who did RIAA in a miniDSP 2x4:

https://www.minidsp.com/forum/hometheater-av-applications/12510-2x4-hd-as-phono-preamp

I have an SHD and I would like to try this. The eq looks easy enough to do. My question is anything else needed to try this? I I using Hana EL cart with the following specs:

• Stylus: Elliptical
• Cantilever: Aluminum
• Output: 2mV
• Output Balance: <2dB1KH
• Tracking Force: 2g
• Channel Separation: 22dB/1kHz
• Frequency Response: 15-25,000Hz
• Impedance: 130ohms/1kHz
• Suggested Load: 47k

Is the signal level too low? If does it need amplified to be useable?

Thanks

 

[SIY]

That's pretty typical for MMs. You'll probably want 20-26dB of flat gain ahead of the miniDSP.

 

[Dj7675]

That's pretty typical for MMs. You'll probably want 20-26dB of flat gain ahead of the miniDSP.

What kind of a device would that be to create the gain?

 

[SIY]

Well... here's where you hit my limitation: I don't really know much commercial equipment. I can just design and build gain bocks as needed. I'd guess that a no-frills mike preamp with a high enough input impedance would work well. Others may have a better suggestion.

 

[Dj7675]

I have seen mention of needing a "flat gain amp" when using dsp based equalization. If I can get this figured out, it seems like a great solution.

 

[Dj7675]

Could a headphone amp be used to provide the needed gain? Something like the atom or something similar?

 

[SIY]

No, you want a very low noise stage with a voltage output (no need to drive significant current or low impedance loads). A mic preamp is much closer to what you want. I know one guy who's using a Scarlett 2i2 and doing the EQ in software.

 

[sergeauckland]

The main problem using a mic amp is that the input impedance of most mic amps is around the 2k level, whereas a MM cartridge needs to see 47k. It shouldn't be difficult to change that, but it needs knowledge of the circuit. Similarly, building a simple 20-26dB gain stage is easy, a 5532 opamp will do it nicely, but that also needs some circuit knowledge.

I don't know of any commercial product that offers the right amount of gain and input impedance, so using software RIAA equalisation isn't straightforward.

S

 

[Dj7675]

Sound like a little too complicated for me. I have been talking to Shannon at Parks Audio via email and he is working on having a digital output option on the puffin which I think would be great to feed into the SHD.

 

[JP]

I use just the flat stage here: http://www.proaudiodesignforum.com/forum/php/viewtopic.php?f=7&t=753

 

[SIY]

I use just the flat stage here: http://www.proaudiodesignforum.com/forum/php/viewtopic.php?f=7&t=753

If Dj can handle a soldering iron, that's a very solid design.

 

[JP]

Works a treat.

If you’ve time to play with the puffin @SIY, e-mail me your new address.