Just upgraded: Hiface EVO!

[Headroom]

http://www.powerstream.com/PST-MP3500.htm

 

Hello I have only negativ concerns about this overpriced product. Rip Off. I had 3 oft them used for Audio recordings in the field often it switches off because loose contact. The plug has internal wires broken after a while. Here in Switzerland its 35 $ and it has a Voltage Converter (buzzing) No On Off Switch everytime you have to dial in for the Voltage.

 

 

[Headroom]

Dont use the bare LIPO. Put several 470uF/16V Rubicon black Gate Low ESR in parallel. Recomended 20 Pieces or more 470uF/16V and cut of the plastic housing from the caps.

 

[57gold]

Why?

 

[Headroom]

Plastic has static electricity and more small caps is better than 1 or 2 big ones. This Ideas coming from Serge Schmidlin

 

http://www.audio-consulting.ch/?Philosophy

 

http://www.audio-consulting.ch/images/file/html/sixmoons/1.html

 

http://refaudiomods.blogspot.com/2010/01/world-class-parts-from-audiocom.html

 

http://www.referenceaudiomods.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=RAM&Product_Code=ACT_1F_WIRE

 

[Part-Time Audiophile]

Is Audio Consulting your company?

 

[57gold]

Why caps and not battery directly into EVO?

 

[Part-Time Audiophile]

The question wasn't "why cut the plastic off the caps" (at least, I don't think it was -- and it certainly isn't mine), but rather, why put a bunch of caps in parallel to the battery at all? Are you trying to regulate the power out of the battery?

 

FWIW, Mike at Tweek Geek thinks that the "battery effect" is probably pretty minimal -- it's something about the regulators inside the EVO.

 

One of these days, I really need to learn this EE stuff better.

 

[Headroom]

this is mine…

http://www.wernergraf.ch/www.wernergraf.ch/index.html

Regulation is not needed the internal stages catches up.

 

Plastic (static electr.) is not good for audio signals, even metal ( or AC lines) close to wires with Audiosignal is not recomended.

A battery is never linear, impedance changes with the Voltage. The chemistry changing the condition. Full loaded and below 1/2 down sound is not good. Good Caps helps... Serge likes huge 250 Ah for feeding. I have 56 Ah for my CD player with Rubicon and Leclanche Paper in Oil and ome woodlense. The 50$ IRiver Optical Out CD Soundsytem (see pdf above) is still a bit greyer and muddier than Computer Audio.

 

Here some infos "Caps" in Powersupplys, they act like a "buffer"

and brings the influence of Chemistry voltage over a wide frequency down.

http://www.seattlerobotics.org/encoder/jun97/basics.html

 

 

 

[Part-Time Audiophile]

I'm thinking that what you're suggesting is probably much improved over what has been suggested, and exceeds -- by a goodly margin -- my ability to handle. I'm guessing that you'll not only need an armful of caps, but something to mount them on and traces/wiring to connect them all. The caps alone are, what, $10 each? Adding 20 caps would be adding (at least) $200 to the total cost, no? Which takes this $100 battery PSU to (probably well north of) $300. And it still doesn't have any method to "automagically" charge itself.

 

The Black Lightning is looking more and more interesting.

 

[Part-Time Audiophile]

Looks like the Black Lightning got the LiFePO4 upgrade, and are now running $900 for 5aH and $1200 for 10aH.

 

Eeek.

 

[barrows]

not needed when using LiFePO4 batteries. While a bank of caps as described above is a good idea if using common Sealed Lead Acid batteries, as noted, to reduce the output impedance over a wide bandwidth, this approach is of no benefit when using LiFePO4 batteries, and actually will hurt the performance. The output impedance of LiFePO4 batteries is actually lower than that of the capacitors. These new school batteries are an entirely different thing than the common SLAs, as they have internal resistance and noise at vanishingly low levels, better than any cap. Also, no voltage regulation is needed, as the Evo has internal volatge regulators, and will work very well with a wide range of input voltages.

 

[Headroom]

LIFEPO is a good idea, I did not know that Bypassing with caps will hurt.I am a looking right now to change it in my system too.

Golden Rule single cells: If you break this rule, you are pulling the pin on the grenade. Absolutely NEVER Exceed 4.3v/cell, never Discharge below 2.7v/cell, never puncture the cells = NEVER discharge the pack beyond 80% of its capacity 20% remaining. If you do not keep at least 20% capacity in the pack, the cells will have a VERY short life! LIFEPO have 1.5 factor in Ah compared to lead.

Facts: 350$ AGM Lead Batterie 12V 260 Ah = 2,8 mOhms LIFEPO4 A123 3.2 V 20 Ah ?$ Prismatic = 1.2m Ohms but you need 3 in serial for 9 Volt.

Northstar NSB 100 FT 12 V 100Ah 380 $ = 2.5 mOhms ZEOL 5.6m Ohms

 

[Torero]

Have Someone tried different usb cables with the Evo? Are there any improvements?

 

[Headroom]

Just switched form AC/DC to the bare LION thing! ups fantastic and dirt cheap...

 

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170535518546

 

[dudeymon]

Just got the EVO in today - sounds great - using a 9V Alkaline to power it - have LIFEp04 battery and charger on the way.

 

I still sense the sound is a little hard in the mids & highs due to lack of burn-in - at least I hope that's it.

 

What has been your experience in burn-in time requirements?

 

Thanks.

 

[Encore]

Dudeymon, that's a bit strange since you are running on batteries. But your computer and perhaps the USB cable also play a role. How is your computer setup, i.e. how are you feeding bits to the EVO?

 

[dudeymon]

Hi Encore,

 

Using a Laptop w Vista, Foobar with the 192K-Kernel component added, 3' USB cable to the EVO, RCA out to the DAC.

 

Don't get me wrong, things sound very nice, but I was expecting a more full and analog like sound. Maybe I just need to close my eyes and relax with it and quit evaluating.

 

[Encore]

Dudeymon, is 192K Kernel component instead of ASIO or WASAPI? I think with Vista, you have to install one of the two in order to make sure that Windows doesn't mess with the bits. Moreover, as you can se elsewhere, everything matters, including the computer used to feed devices like the EVO ... And maybe the USB-cable, too ... :-S

 

[Encore]

I've experimented more with 9V alkaline battery power. There's no doubt, the sound is more analog-like, with smoother highs. Mids are better defined, and sound stage is more holographic. However, bass is better with my Bolder PSU, deeper, better defined and more authoritative. I wonder whether with a decent 9V LiFePO4 I would get the best of both worlds. Any takes on that?

 

[Headroom]

Sound depends on the capacity of the batteries size deeper internal impedance = more control, less influence the wires and the connectors, LiFePO A123 are best and safest. LION is not as good has some protection circiuts wich gives a higher internal impedance.

The secret of good sound with LiFePO4 is give easy and fast a big amount of current ( many amps) alkaline can not so. The AC powerlines are full of dirt, in the night when everybody is asleep sound is better. And always listen yourself (even if some Bypass caps give a better sound)

:-)

 

 

[Encore]

Headroom,

In regard to your advice: "NEVER discharge the pack beyond 80% of its capacity"

 

Well, that's one of the reasons I'm a little hesitant to go the battery route. If you are to gain the full benefit of battery operation, you probably have to disconnect the charger from the battery, i.e. you have make darn sure that you remember to reconnect it before it runs below 20% capacity. It's very unlikely--at least for me--that this won't happen over the course of, say, the three years that a 1000-cycle battery should last you.

 

[barrows]

"deeper, better defined and more authoritative. I wonder whether with a decent 9V LiFePO4 I would get the best of both worlds. Any takes on that?"

 

Yes, LiFePO4 batteries will produce the best of both worlds. The difference is the LiFePO4s have much lower output impedance (internal resistance) than other batteries. This means they can deliver huge amounts of current virtually instantaneously.

Another option would be to use a really good shunt regulated AC supply (Paul Hynes, Twisted Pear Audio), powered from very clean AC. I use a modded PS Audio P-300 to supply super clean, regulated, AC power for my preamp and DAC. In my new DAC build, I am going to ditch the LiFePO4 (digital) supply for an internal shunt regulated supply. I suspect this method will perform at least as well as the LiFePO4s, without any charging hassles.

 

 

[Part-Time Audiophile]

Barrows -- I seem to recall you talking about your PS Audio P-300 somewhere once, a million posts ago, but could you (would you?) give a description of what it is and why its different and how we can either get one or make one?

 

Batteries seem like a PITA. I'm wondering if I couldn't do better getting a regenerator for all my digital needs (computer, converter, CD player and DAC). Don't they generally have good/better isolation (socket pair to socket pair, as well as, unit to rest of home)?

 

Batteries seem like the way to go, but they hassle doesn't sound like fun. And getting Black Lightning units for everything is way pricey.

 

[Encore]

Well, just switched the Vincent power cord feeding the Bolder PSU to a DIY cable consisting of Oyaide M1/F1 connectors and DH Labs power cable. What a difference! It surpasses the 9V alkaline, certainly in terms of dynamics and bass, but even the highs are smoother, I think.

 

The Vincent power cord is not terribly high end, and I have noticed a tendency to graininess across the board, also when used with non-digital equipment. However, with my Sq.box Duet I didn't notice any improvement when going to a better power cable.

 

My Oyaide-equipped DIY cable also gives smoother highs with my, but the effect is even more pronounced with the EVO.

 

With this improvement, I don't think I'll bother pursuing the battery route ...

 

[barrows]

The P-300 is PS Audio's original AC regenerator. A true regenerator works like this: take incoming AC and convert it to DC-generate an entirely new, low distortion, low noise, AC waveform using a signal generator-output the new waveform through an amplifier stage using the DC as supply. In theory, an AC regenerator makes an entirely new AC supply, eliminating noise, waveform distortion, and regulating voltage in the process. A good AC regenerator also features much lower impedance than the wall AC power, so unlike traditional power conditioners, a Regenerator can actually improve dynamics, by speeding up current delivery.

The downside is that regenerators are complex (think signal generator plus power amplifier) and inefficient.

The P-300 is rated to produce about 300 watts of power, and is suitable only for source components-I prefer to keep the load on a P-300 below 150 watts for best performance (like a power amp, distortion will be lower at lower outputs). The P-300 also outputs balanced power.

These units are available on the used market, if you find one, I would recommend having it sent to Rick Cullen for evaluation and modding. At the very least have him replace all the capacitors, as they will be dried out. Unlike some other regenerators, the P-300 uses a low noise, linear power amplifier stage, so it can perform at a much higher level.

Mine did not work that well stock (the main power supply caps were dried out)-but when I replaced all the caps it worked fantastically with my preamp and DAC. Like any active device, it responds well to modding with quality components.