I played hooky and got together with some folks over at Mike Galusha's place yesterday. Jerry and his super deluxe power supply joined us, as did Greg, from nearby. We had met Greg a few times before at Chris Brady's (Teres Audio) get togethers. He wanted to take a listen to various modded SB2s and power supplies.
It has been about a month since I built the Super Deluxe Power Supply and most of the break-in should be over. It would give us another chance to compare battery supplies vs AC.
All power supplies were first powered through Mike's BPT balanced power transformer. All of the Squeezeboxes were run from their analog outs direct into Mike's amps. The first up was the stock switcher plugged into Greg's stock SB2. VERY harsh and edgy. Changed to a BOLDER Basic rev 1 PS and the harshness went away. Greg was surprised at the, to him, major change in the sound.
We then changed to a slightly modded SB3. This one was modded for digital out only, but some of the mods will effect the analog out. It was smoother than the stock SB2, but not by a lot.
We switched to Mike's modded SB2 and the sound really opened up, being VERY smooth and natural. He has a pair of Sonicap Platinum Bypass caps installed. Gone was all trace of harshness and edginess. We switched to the Deluxe power supply and heard a small amount of improvement. Both the Basic and Deluxe had bypass capacitors and only about a week of use on them.
We then inserted my SB2. This is a fairly over the top version with Sonicap Gen 2 bypasses on the output caps and a pair of Silver Slipstream Bybee in the signal line. This was the most refined player. ALL the detail that was available came through with no hint of grit or grain. Smooth and refined and expensive. The Silver Slipstream Bybees ARE $200.00 EACH!.
We then put in Jerry's Super Deluxe Power Supply. This was the bassis for my redesign of the Basic and the design of the Deluxe. He has a pair of 5 Ah 12 volt SLA batteries going into a good sized capacitor bank with bypass caps and then going into the 5 volt regulator circuit. The AC is about the same with the HexFREDs physically away from the transformer feeding the same value cap bank and then going through a switch into the regulator board.
After listening to the SDPS for on AC awhile, we switched to Battery. At the same time we removed the AC power cable so no interferance from the transformers field might interfer.
It took just a little A/B'ing listening to Ray Brown before we all agreed the the battery had FAR less low end extension and dynamics. The "snap" of the bass strings just wasn't there. When the system was running on AC all the dynamics, and extension came back.
This was very defining for me. It proved to me that a very good AC based power supply can sound better with the Squeeze box than a battery based sytem can. At least in this sytem it did.
There was a small amount of noise increase in the AC powerd section, but I believe I know where that is coming from and I can remove it. I have Jerry's power supply on hand now and I will be working on it to see if my therory is correct. I will be using what I find out on all the power supplies I offer from now on. All of the Basic rev 1 supplies are using it already.
The other thing we listened to came as a bit of a shock to every one. After listening to Jerry's supply a few weeks ago, Mike decided he needed to build one even better, or at least bigger and heavier. He was given a couple of old Carver amps that were blowed up real good. He gutted one of them to use as a case for his PS. He had some of the transformers used to make a Felecia balanced PS, so he built that into the case. He then used about the same parts I used in Jerry PS. It is a little over kill as he already runs balanced power from his BPT into the Felecia. It barely had a hour of use when we listened to it.
At first it sounded not too bad, but VERY harsh in the mids and tipped up in the highs. About what I would expect with a PS with 13 brand new capacitors in it. After some fiddling about we decided to try out a few different AC power cables with it. Mike was using a Nitro Plus cable with Furutech Rhodium Plated ends. I lent Mike some of a Custom run of power cables I built for a client who has yet to pay for them. They are using Oyaide male and female ends with a pair of Bybees in each cable. The whole assembly was then Cryo-Treated.
There was a stunning difference. Mike's PS no longer sounded like it needed break-in. It was smooth and extended. We then tried it in comparison to other cables on the other supplies. In all cases the Bybee cable improved the sound considerably.
In most cases I would say that cable is major overkill as it retails for around $1000.00. It did however make a major improvement.
The next round of power supply upgrades will consist of adding a pair of Bybees to the AC line before the rectifiers, If it can come close to the sound of that power cable, that will be money well spent. That would be a $200.00 option on any of the PS.
I am also going to try a Jensen four pole cap after the rectifiers,. This should remove even more noise. I feel some of the noise we heard from Jerry's PS on AC was caused by the grounding scheme. I will correct that and then take another listen
Overall I was VERY pleased with the results of this listening session. I proved to myself and to others that a good AC power supply DOES sound better, in that system, to a battery power supply. I was also pleased to discover that Bybees have a very beneficial effect on the power going to the SB2 and in the signal line.
I will be offering options to the mods to add Bybees, shortly.
