In his video of May 14, 2020 Paul mentioned that Darren Myers is working on a new phono preamp, which is going to fill the gap between the Stellar Phono (2,500 ) and the coming BHK Signature Phono, which will be a two-box phono stage and quite out of the financial reach of many phono lovers (20,000 ).
Would Paul, or somebody else, care to shed some more light on this upcoming product?
P.S. After having reviewed several phono stages over the years I pulled the trigger on the Stellar Phono, picking mine up tonight.
Darren’s in the middle of working on the PerfectWave Phono Preamplifier. This is a step up from Strata (in the Stellar line) and will be in the same chassis as DirectStream, etc.
It’s going to be quite the preamp when he’s done. Currently he’s evaluating sonic differences in resistors. It’s a long design process that he’s very good at.
Signal to noise performance can and usually is better in a JFET design but wasn’t the driving factor. It’s important that we don’t generalize on the circuit building blocks. Tubes can be awesome but the SPP has taken down many competing tube designs. It’s a matter of implementation.
The Stellar Phono is actually solid-state and does not contain a tube.
This project is VERY early in its development life. For that reason, there’s not much I can say because there’s so much to be defined.
What I can say is that I’m extremely excited about what’s ahead!
There’s something I always wanted to ask a phono amp designer:
Impedance setting for a cartridge is often used for top end tonality matching to personal taste. Is there just one correct setting for other electronic reasons or in which range it’s a matter of choice without other downsides like loss of dynamics etc.?
The purpose of the loading resistor is to damp the response of the cart, which provides a flat frequency response and avoids large transient related issues such as overshoot/ringing.
Every cart has different electrical properties, which means that the loading that will work best for it varies from pick up to pick up.
However, there are SO many other factors that determine what the best loading for will be. We all know how not only the set of the cart such as VTA/VTF affects the sound, but even the cartridge/tonearm compliance compatibility matters. On top of all of this, ones own preference for tonality and high frequency accentuation can play a large role in where that loading is set.
It’s a journey but analog can be so darn rewarding when you get it right.
If we put a square wave into the input, ideally we should see a perfect square wave on the output. A diving response, which could be due to an over damped system, will roll off the edges of the square wave due to the circuit not being able to reproduce the harmonic structure. If the response peaks due to the system being under damped, the square wave can show overshoot and ringing. This is one of the reasons why it’s important to damp the cart and not run a MC into say, 47K unless the manufacturer specs this.
True with the rabbit hole, but for tubes it’s mainly so if we speak of strong power amps, the rest is quite easy.
And for the tiny signals of phono it’s certainly not optimal unless extremely elaborate and costly. Below that, the best sounding solid state are mostly better in many relevant characteristics imo.
In my case by listening tests it turned out that at values considerably below the optimal, some attack gets lost and above optimal at high values it can get a little fatiguing and tonal colors get lost.
