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Romy the Cat wrote:

Today turned the playback and I was surprise with gray and unexpressive bass. “What the hell?”-  I asked myself. There was absolutely nothing done to playback but I look like I lost bass. My initials sentiment was that at cold temperature my drivers in midbass horn in attic got too stiff. I check with my radio transmitter that I left in back chambers and it looks like both temperature and humidity were fine. Then I stick a scope in power line. The AC was pretty bad, not the worst I have seen here in West Woburn but bad, with a nice horizontal square atop of the wave. The wave after the PP2000 was fine of cause. So, what is the problem I wondered?  After some thinking I made a conclusion that the problem is most likely that PP2000 is semi-transparent to the AC problem of externals line, despite that it outputs a fine wave shape. The only experiments that I was able to do is to run PP2000 from buttery and compare it to what PP2000 does what it runs from AC. This time it was very sorry unfortunate test. As soon I shot down at all 3 PP2000 AC input and the PP2000 switch to own battery I immediately got my bass back. It was so obvious and so apparent that it count not be even second thought what was the problem. I was listed a few opening bars of Tchaikovsky’s Second Movement of the 5th symphony (guess by who?). The opining cellos and basses has a lot of texture, transients and “strings bite” when playback runs from PP2000 buttery. As soon the PP2000 is switched to run from AC all bass colors are gone, the values of transients are filled with gray noise and the distinctions between the bass notes are virtually gone, Sound become boring like hell… So, something is certainly is very wrong.  The very first PP1500 unit that I got 3 years back had absolutely no difference in sound between running from butteries and running from AC. My unit #7 that was very nicely working in my home foe over a year had very minor between butteries and AC, practically negligible difference. Those 3 new units had huge between butteries and AC. I am afraid that PurePower peoples loaded capacious into the units to suppress the HF residual spikes that they had from buttery charger and accidently they killed the Sound of the things. I mention it because you will have the absolutely the same effect if you add capacitors to the primary of your PS transformer – shunting caps on AC lines kill bass… Anyhow, I am not convinces that it is the PP2000 fault – I have 3 units and I need to make the same test running everything from one units as 3 units give some ambiguity. However, there are very strong evidences that the last PP2000 has issuers. I might not detect it when my AC will be in better shape but today ether my AC or the PP2000 running not from butteries are truly horrible. It is sad as I did not sign for THAT.

The news are mostly bad. Sonically the new regenerators are dead. In facts the open power lines do sound better than new PP2000.  The two new units are the worst – they are hardly usable sonically, my old unit that PurePower update to the newest version is a bit better then the brand new PP2000 but it also is very far from what my old PurePower unit did.  Ironically all the PP2000 measures way better than the previous units…

Let me to explain what the new generation of the PP2000 does to sound. Pretend that sound is a stormy ocean with ocean waves are the tones of different colors and different amplitude. So, what the new PP2000 does is injects into the each valley between the wave some kind of white noise that make the tones-waves less animated and less considerable. It is not juts bass is none-existing with new PP2000 – it is the whole sound become less expressive and very boring.

Now, here is the interesting twist. When the new PP2000 runs from buttery then the above-mentioned effect is not there and sound is very fine – exactly how my old PP2000 sounded from AC lines.

So, what does it mean? It means that PurePower change something in the input side and did not tested sonically what they do. PP2000 has in input blocking filters, rectifiers, most likely DC-DC converter that drops voltage to buttery level and some logic around it. Something they changed that killed sound, I am sure that know what they did.

One mode ugly thing. My old updated PP2000 is much better than the other 2 new units, so I use the only one PP2000 to drive all my system. My old PP2000 was able to drive my old system from buttery for 20-30 minutes. The same unit “updated”, having the same 60% load shuts itself down after 2 minutes and 86% of buttery discharge, indicating that buttery is too low. So, ether the PurePower replaced buttery in my unit and put in a dead one (I very much doubt) of the new butch/version of PP2000 has faulty logic for buttery operation. BTW, the buttery operation logic is located on the same “input side” that is most likely responsible for major sound screw up.

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