Grimm PW1 phono pre-amp – Where the Magic Happens

Intro

We have rarely spent so much time on a review. Multi-tests always take a lot of time, of course, but a “single review” where we spent more than a month: that doesn’t happen very often anymore with your author. The reason: we simply couldn’t stop listening to music! The instigator? The Grimm PW1 phono pre-amp.

Your author is painfully aware that he once told colleague Yung Lie that Alpha is about streaming audio and that no vinyl will be tested. But hey: times change. And so do insights and opinions. Vinyl is just fun. It’s a pleasant addition to the hobby. And it can coexist excellently with the streaming setup….

Experience

Let’s start by mentioning that playing a record is a totally different experience that starting a music stream. Is it the quality? No… not at all. A nice vinyl setup sounds no better (or worse) than a decent streaming setup. Both can thrill you. And from both setups your author enjoys intensely.

So why change tack so suddenly? Simple: vinyl brings your author something new. Again, there is a lot to discover. From adjusting an arm to matching a phono pre-amp to discovering which cartridge fits the arm and table well. It’s just a lot of fun.

But also taking the record out of the sleeve. Looking at the artwork… Washing the records you were able to score at fairs and marketplaces…. And collecting original, first pressings; it’s all part of it.

The Grimm PW1

But let’s get back to the subject of this review for a moment: the Grimm PW1. We recently interviewed Peter van Willenswaard (the lead designer). You can listen back to this interview below (or via Spotify, Apple) or of course watch it back on Youtube.

The gist of Peter’s story is that the Grimm PW1 is completely designed for low noise and speed. The toroidal transformer was developed together with Amplimo so that it can be built in without creating hum. Furthermore, all power supplies are internal shunt power supplies (both Peter’s and Guido Tent’s are used) and the number of capacitors is kept to a minimum. This is because they actually at any time have an impact on playback (especially phase and timing).

By looking critically at each component and minimizing the number of components, a low noise floor has been realized. You can see that later in the measurements. We measure almost -100dB at the MM input. That is very low; lower than our own Primare R35.

Interview Peter van Willenswaard

Minimalist

The cabinet design is also very minimalist. It is a compact cabinet, with one line optically “breaking” the cabinet. Simple; elegant. Although, of course, that is also a matter of taste.

On the back we see a particularly large number of connections. Two sets of inputs: MM and MC. And both balanced and single ended. Balanced can be a bit cramped if you use a large power plug, as we do. Grimm did rotate them a quarter turn for convenience. At the center of the back panel is the connection for ground.

Setting

At the bottom we see all the dipswitches to match the player to the Grimm PW1. The “boxes” separate settings for MC and MM. And for left and right. They are completely mirrored, showing that the pcb design is also neatly mirrored. There is also a separate section for gain and switching between MM and MC. Everything, by the way, you can just adjust while playing; there are no clicks, pops or other side effects.