[se-riously]

After putting in the Sonicap Gen I input caps with Platinum bypass caps, I've burned them in for 125 hours.  I know there's still a long way to go for the caps to be completed burned in, but I wanted to replace the power supply now because I couldn't stand the stock 24v power supply any longer.  Here are the parts I used:

1)  One spool of 16 AWG copper stranded wire (from auto parts store since Radio Shack didn't have any) - $6
2)  Four F1 (3/16") connectors - $4 (for a pack of 20)
3)  One fuse holder from Radio Shack - $3
4)  Package of 6.3A slow blow fuses - $3
5)  Two Powersonic PS-1250F1 sealed lead acid batteries - $33 shipped from Amazon
6)  Soneil 24V 2.0A Model 2405S charger from E-Bay - $25 shipped.  You can also buy a Soneil 24V 2.0A charger here for $45 + shipping, which is about the same price (if you add alligator clips) as the Powerstream A100-24 charger.

http://www.batterystuff.com/battery-chargers/24-volt/gel-cell/Son2404S.html

I already had silver solder, soldering iron, shrink wrap, crimper, voltmeter, zip ties, etc. so the total project cost was $74 (the savings went toward a Sylvania GB 5751 triple mica gray plate for the Dodd buffer).  I re-used the 2.1/5.5mm barrel connector and a portion of wire from the stock power supply that the M451 comes with (which puts out 23.8v by the way).

Here's the photos of it without the Soneil charger connected:


Two batteries taped together.  Note the red zip tie for (+) and black zip tie for (-).


Fuse holder.  GOTTA HAVE IT!


Stock barrel connector and some stock 18 AWG wire - reused (starts where it changes from red to black).


I do have a few questions:

1)  Should I have twisted the pair of wires?
2)  Should I cut off the ferrite at the end, close to the barrel connector?
3)  Should I have used a new barrel connector since the stock wire is 18 AWG, or shortened the stock wire segment?
4)  Should I reduce the overall length to the bare minimum?
5)  Should I use a different fuse value?  (I thought I read 6a or 6.3a was perfect for soft-start, i.e. 2010 amps)
6)  Any other recommendations?

As far as initial listening impressions, this is a must do.  Any replacement of the stock power supply is a must do.  The harshness from the stock power supply is gone, soundstage depth has vastly improved, instruments sound far more natural, vocals are easier to discern, blah, blah, blah.  One thing that concerns me is that I still get a bit of hiss that's audible from about a 1-2 feet away from the tweeters from my GR Research OB5's  (91.5dB sensitivity).  I was hoping for dead silence, which is why I'm asking the above questions.  I'm still using the stock JJ tube right now.  Thanks in advance.

[virtue]

Looks like you rocked it!

1)  Should I have twisted the pair of wires?

No need.

2)  Should I cut off the ferrite at the end, close to the barrel connector?

It affects RFI at frequencies you cannot hear.  Don't sweat it.

3)  Should I have used a new barrel connector since the stock wire is 18 AWG, or shortened the stock wire segment?

Getting spooky on me now.

4)  Should I reduce the overall length to the bare minimum?

See above... spooky.

5)  Should I use a different fuse value?  (I thought I read 6a or 6.3a was perfect for soft-start, i.e. 2010 amps)

Perfect value, slow-blow is good.

6)  Any other recommendations?

You rocked it.  Nice job!

Slight hissing... yip, normal.  Never bothered me and we'd probably need to toss Tripath to get rid of it completely.  You wouldn't want us to do that now would you?  Our Tripath children have poor manners sometimes but are overall, delightful!

[se-riously]

Thanks for clarifying Seth.  With the Soneil connected, the voltage stays at 27.6v (big jump from 23.8v).  Charger light stayed green even after a 2-hour listening session last night.

[julcat]

Nice work!!!!!!!

Where in ebay did you get the chager???

......
6)  Soneil 24V 2.0A Model 2405S charger from E-Bay - $25 shipped

Thanks

[se-riously]

Where in ebay did you get the chager???

It was a while back, and just a private seller that was selling electric wheelchair / scooter equipment.  I've updated my first post that includes a link to where you can buy a Soneil 24v 2.0a charger for $45 + shipping, which I consider to be a no brainer compared to a Powerstream equivalent.

Now that I've hooked the battery supply for a few days, I've noticed something recently.  When I have the charger connected to the batteries and the charger is plugged in, I do hear a very, very, very faint high pitched whine when the Sensation is on and it appears to be intermittent.  It makes no difference if the charger light is green or yellow.  My speakers are 92dB efficient, and I do listen to material with some quiet passages, so I may be more susceptible than others.  It drives me nuts though, and the whine disappears the moment the charger is unplugged.  I know that this charger is supposed to be "nearly indiscernible" when connected, but I can instantly tell a difference.  Maybe I have "golden ears".   

So, I will modify my battery supply to add a simple digital Xmas light timer to the Soneil charger, which I'll program to charge the batteries in the middle of the night when I'm not listening and automatically disconnect the charger when I'm more likely to be listening.  The batteries should give me around 4-5 hours of listening time before needing to be charged so that's plenty for me.  If I need more amp-hours, I can always add another pair later.  Given what I now know, I'd probably purchase a minimum 7.0Ah batteries just for the additional headroom, less deep discharge (which adds to battery life), and reduced voltage drop over the same listening period compared to 5.0Ah batteries.  The price difference between a pair of batteries is only $7.  Of course, the trade-off is size and weight if you're trying to fit the batteries into a specific case / project box.

[se-riously]

UPDATE: 11/16 @ 7:05 AM.  Turns out my Soneil charger went bad.  I guess I deserve it for buying one for cheap on E-Bay. When I plugged it in late last night, I heard a 'pop', it felt pretty warm, the LED on the charger went out, and now something's rattling around inside.  Not good, but a lot better than a battery exploding or fire.  So time to get a new charger, and maybe the whine I was hearing was just the charger going bad, and maybe I don't have golden ears.   

[wsturner]

That really sucks! Let us know if you hear anything with the new charger. I don't know anyone else who has been able to detect when the charger is hooked up. Except OzarkTom - who is always contrary

[Jason T]

I have one of these I bought about a year ago.
no problems yet.
http://www.zbattery.com/24v-1-5a-3-Stage-Sealed-Lead-Acid-Battery-Charger-CH-LA2415

[OzarkTom]

That really sucks! Let us know if you hear anything with the new charger. I don't know anyone else who has been able to detect when the charger is hooked up. Except OzarkTom - who is always contrary

I hear a tad , just a tad of electronic hardness, and the focus is better without the charger on.

[se-riously]

I have one of these I bought about a year ago.
no problems yet.
http://www.zbattery.com/24v-1-5a-3-Stage-Sealed-Lead-Acid-Battery-Charger-CH-LA2415

I thought I read in another thread that you typically leave the charger disconnected during listening sessions, and that you were going to try listening with the charger connected to see if you can hear the difference.  Could you give us an update?  It would be interesting if the charger you have listed is an equally good, low cost alternative to the Soneil or Powerstream.

Btw, the replacement Soneil charger from batterystuff.com arrived today (2 business days from Oregon to California), which is really good service.  I'll hook it up tonight and update this thread accordingly.

[Jason T]

I thought I read in another thread that you typically leave the charger disconnected during listening sessions, and that you were going to try listening with the charger connected to see if you can hear the difference.  Could you give us an update?  It would be interesting if the charger you have listed is an equally good, low cost alternative to the Soneil or Powerstream.

Btw, the replacement Soneil charger from batterystuff.com arrived today (2 business days from Oregon to California), which is really good service.  I'll hook it up tonight and update this thread accordingly.

I should have been more specific.
the charger I listed has very VERY low noise floor on my system but its so little that I dont hear it unless I stick my ear to the tweeter.

I never unhook/unplug my charger while listening.
some people might be able to hear/tell a difference but I cannot.
$25 is hard to beat.

my brother works for a mobility scooter repair facility so I got to play with 5 different chargers ranging from $25 (the one I provided the link for) all the way up to a $200 quick charger.
the lower amperage chargers were much quieter (as would be expected) so I chose the smallest of the bunch.
the 1.5Amp charger will handle up to 20AH batteries which is more than enough for our applications.

From what I hear the Soneil chargers are worth the extra $ so I would stick with them as long as they're working.

[jtwrace]

I use a C-TEK charger on my Dodd Buffer.  It's a true "smart charger".  That's very important. 

[se-riously]

UPDATE:  11/19 @ 12:45 AM.  I hooked up the replacement Soneil charger from batterystuff.com.  FYI, the charger comes with a male XLR connector, which is designed to plug into mobility scooters / electric wheelchairs.  Since I didn't feel like buying a female XLR connector, I just cut off the connector and soldered accordingly.

As it turns out, I (mostly) don't have golden ears.  With the new charger, there is no increase in any hiss and, thankfully, no intermittent faint high pitched whine.  The same can be said with the charger light in yellow or green mode, so it's safe to say that the noises I was hearing was simply the impending death of my previous charger.

As OzarkTom mentioned, I do however hear a very, very slight increased "electronic harshness" in the high frequencies and/or reduction in focus, but I can only identify it when listening to extremely dynamic tracks with silent passages in between.  For most music, I don't notice any difference so I think the term "nearly imperceptible" is appropriate.  So, I'll leave the charger connected at all times, which is a good thing because......

One thing I found out is that the tube buffer can drain your battery pretty easily if you don't turn the rear switch off.  I think it draws 300mA?

UPDATE 11/28:  I think I like it more without the charger connected more.  I figured that I should get the most out of what I have, so now I disconnect the charger when I'm listening.

[julcat]

Could you please post a picture of your final setup, does you have the soneil battery charger and your Sensation connected at the same time??

[se-riously]

Could you please post a picture of your final setup, does you have the soneil battery charger and your Sensation connected at the same time??

Yes, the charger and batteries are connected to the Sensation at the same time.  Yes, I can post a photo of the "final" setup tonight.  Notice the quotes because right now everything is just thrown into a small cardboard box right now for the "half assed ghetto" effect.   

[se-riously]

As promised, here's two photos of my "final" setup.  As you can see, the only thing I added here was the two leads from the Soneil charger now connected to the battery terminals.  i wanted everything to be insulated, so I did not use alligator clips, and I put a piece of electrical tape over each battery terminal.







I'll probably add a rocker switch to the Soneil's positive lead so I can "quick disconnect" the charger (rather than unplug it) during critical listening sessions.  Right now, everything's just in a cardboard box.  I'm thinking about putting it all in a nice wooden box, and adding a digital in-line voltmeter so I can monitor the voltage when I do critical listening without the charger connected to avoid over-discharging the batteries.

One idea I've been thinking about (inspired by Red Wine Audio) is the use of LiFePO4 batteries instead of sealed lead acid.  Specifically, these 2 products seem appropriate as a substitute for the SLA/Soneil combo, but since I haven't tried it, I can't tell if there are any sonic benefits and if the charger itself is "nearly imperceptible" too.  The LiFePO4 batteries are supposed to have lower impedance (which delivers current faster), their voltage drops less over the same discharge period, and they can be recharged for more cycles.

http://www.batteryspace.com/Customize-LiFePO4-18650-Battery-25.6V-4500-mAh-115Wh-13.5A-rate-3Rx8.aspx
http://www.batteryspace.com/Smart-Charger-1.2A-for-25.6V-8cells-LiFePO4-Battery-Pack-100-240VAC.aspx

But based on the e-bike forums, it seems like this product is the tried and true.

http://www.pingbattery.com/servlet/the-4/24V-10AH-V2.5-LiFePO4/Detail

[virtue]

Does that include shipping, JT?  My customers need a deal!

[jtsnead]

Guys

if you don't want to tackle the power cord I can build them for you.

Jason,
This would replace the thin cord that came with my charger for my 901
from battery to 901, correct?

[Jason T]

Does that include shipping, JT?  My customers need a deal!

sure I'll ship them free to anywhere in the US

[Jason T]

Guys

if you don't want to tackle the power cord I can build them for you.

Jason,
This would replace the thin cord that came with my charger for my 901
from battery to 901, correct?

that is correct.
I'll ask when you order which amplifier you have so I know which plug to put on the end.
if you have both one of our smaller amps and a Sensation then we'll have to work something out.

this will make it so you dont have to use the adapter dongle on your power cord.