P20 overheating and shutting down with specific audio components — seeking technical explanation

Yeah, but I’m in SA … we don’t have steady power grids like you guys. Then again, I do have the Victron “in between” Might be an idea to have Victron to Transparent PowerWave X to Gryphon to AP20 / TV / NH10.

I might consider such a move. But I’ll stick to my mid-tier PC’s from Gryphon to components. That part of my “tweaking history” is history :rofl:

Absolutely a more reactive load will make the P20 run harder. I switched from a hybrid electrostatic speaker to a dynamic driver speaker. The power draw was nominally 625 watts on either set. But, the heat generation was significantly lower with the less reactive dynamic driver speaker, all else was the same.

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Did you change anything or did it all of a sudden start to act out? Can you go back to the old loads and test the stability?

Best, Galen

You can’t run the P20 on a 15 amp breaker and get the P20’s rated output, it is a P15. I ran mine as a P15 and recently upgraded the wall circuit to a dedicated true 20A 12 gauge line to the fuse box with a 20A breaker. Opened the back panel and switched to the C19 cord. I’ve never had an issue with the P20, ever. My entire system is powered @ 625 watts draw at typical listening levels.

The problem here seems to be a super high reactive load on the P20. This is murder for even the line to your house and why plants use power factor correction to keep the load resistive. Our house isn’t really different from that, but PF is ignored.

Best, Galen

Thank you Galen

From my DB board, I’ve run a 6mm twin & earth cable on a 20A breaker to a dedicated plug for my HiFi. My P20 was always happy with it using BHK 300’s, BHK Pe, PST Transport, Samsung 85 inch TV and DSII DAC.

I recall when I added a Rose RS150B the P20 also seem not to like it (overheated), but at the time I wrote it off to a loose connection on one of my LI batteries. In hindsight, I do not think so any more.

Then I moved my room from “tunnel” to “landscape”. As I did not want to move the power plug, I used a professionally made up extension cable. Poper grade 3-core 2.5mm core, with the best SA plug I could find and a proper audiophile IEC on the other side. With this configuration my old system was quite happy.

When the Aurender stuff arrived, the problems started. I called my electrician, who blamed the plug outlet and replaced it, properly testing it on both ends. My HiFi friend blamed the IEC end, which he thought felt somewhat loose when plugged into the P20. I replaced that with a decent Transparent IEC. With the electrician still present, we tested the cable with a proper draw. So I can say with confidence that we eliminated everything from DB board to P20 as a possible contributing factor. And the problem remained, the P20 kept going into protection mode - just with the AP20 on idle.

But: What you say about the PF makes sense. I’m not so much technically minded. I recall that many years ago, PSA had an ampifier with a switch mode PSU that used to create havoc on the power plants of the time, due to this problem. But, the AP20 uses 6 Toroidals, not switch mode PSU’s: 2 x 400VA for the Eigentakt modules; 2x50W for the DAC; 1x50W for the CPU and 1 x 25W for the FPGA. According to Gemini, 975VA total.

Gemini furthermore says:
The Aurender AP20 overheats your P20 because its massive 975VA linear power supply operates at a low power factor. Instead of drawing power smoothly, it pulls current in violent, out-of-phase spikes at the peaks of the AC wave. The P20 acts as a literal amplifier to recreate your power; fighting this highly reactive, inductive load forces its output transistors to dissipate massive amounts of energy as pure heat, triggering thermal shutdown even when the Aurender is just idling.

The Aurender NH10 blows the fuse due to massive inrush current upon startup. Because its specialized audio-grade toroidal transformer and oversized capacitor banks are completely empty when cold, they act as an instantaneous short circuit for a fraction of a second. This massive initial current surge hits the P20’s fast-reacting output rail like an electrical sledgehammer, instantly overloading and snapping the fuse before the hub can initialize.

This is exactly correct. As an example, take a small AC to DC power supply with an internal digital pulse power supply. Leave it UNPLUGGED but “on”. Now plug that raskel into the wall and watch the sparks fly from the AC outlet! The in-rush current is infinity for the inital voltage supplied to the DC supply.

Add the fact that these are also reactive as the dickins, as you point out, and it drives AC systems crazy. Nothing is really made to tolerate reactance. Nothing. Some stuff can just tolerate it better as the power factor is an aggregate of many items such that the load is resistive enough overall. Isolate just a single circuit and that average load can easily be too reactive.

Best, Galen

Interesting reading here… Fortunately I can’t say I’ve experienced anything similar with my P15 which I mostly now use for my HT system (Epson Pro Cinema LS12000 and Marantz 8015 with 7.2.4 Atmos). Knock on wood, no issues and I’ve had all of these connected for a few years now.

I have to concur with the previous statements about the passive Gryphon PowerZone… it just improves everything on my 2 Channel set-up! :smiling_face_with_sunglasses: