New TK2050 board

[erozsolt]

Originally Posted by col

I have a modified ConnexElectronic SMPS250 (one of the older ones) it works very well and is much smaller than the "brick" SMPS. I think Cristi has created one SMPS that is single ended so you don't have to modify it, SMPS500R-Single.

col.

Sorry does single ended PSU mean that its has a 0 and a 36V instead of +-36V? It says that the new SMPS300R is available in both configuration (but I don't understand that much about PSUs).

[col]

Originally Posted by erozsolt

Sorry does single ended PSU mean that its has a 0 and a 36V instead of +-36V? It says that the new SMPS300R is available in both configuration (but I don't understand that much about PSUs).

yes, single ended is just 0v and +v. You need this for the T1 and T2.

[erozsolt]

OK, I understand it now. It says this on the webpage:

Can be configured for for either dual output voltage, or single output voltage, in range of +-30V to +-72V or 24V to 72V. The stock available output voltages are adjustable within +-10% range.

Do you think this means that the same product can do both and all voltage range, or I have to order a specific one?

Update: I asked Cristi to have a look here.

[col]

Originally Posted by erozsolt

OK, I understand it now. It says this on the webpage:


Do you think this means that the same product can do both and all voltage range, or I have to order a specific one?

Update: I asked Cristi to have a look here.

I think you need the 24v one and then you just adjust it up a bit.

[erozsolt]

Originally Posted by col

I think you need the 24v one and then you just adjust it up a bit.

I hope Cristi clears up that part, because on the website, the other PSU-s have a swich where you can select which version would you like. If I choose the T1 510, I'd really like to have 36V. A 24V + 10% could only do 26.4V. If 36V is not possible on a SMPS300R then I'd go with a better Meanwell.

[erozsolt]

Or for the ultimate solution: 10-11 cells of A123 batteries in series.
Like these:
EP Buddy 7S1P 23.1V 2300mAh LiFe battery pack USA A123 | eBay UK
EP Buddy 4S1P 13.2V 2300mAh LiFe battery Type2 A123 USA | eBay UK

[mootzeroni]

Originally Posted by erozsolt

Or for the ultimate solution: 10-11 cells of A123 batteries in series.
Like these:
EP Buddy 7S1P 23.1V 2300mAh LiFe battery pack USA A123 | eBay UK
EP Buddy 4S1P 13.2V 2300mAh LiFe battery Type2 A123 USA | eBay UK

I hope you mean to say in parallel, and for goodness sake don't use LiPo instead...

YouTube - Lithium Polymer Battery Explosion's (liposack)

[erozsolt]

Originally Posted by mootzeroni

I hope you mean to say in parallel, and for goodness sake don't use LiPo instead...

YouTube - Lithium Polymer Battery Explosion's (liposack)

I think I won't invest in such a thing now, as it's a bit more expensive for me now, but I don't understand why would it be dangerous (with a proper charger). And I mean in series. Connecting 11 pieces of 3.3V cells in series is 36.3V. Charging them with a balanced charger wouldn't be a problem. The A123 cells are LiFePO4.

[mootzeroni]

Originally Posted by erozsolt

I think I won't invest in such a thing now, as it's a bit more expensive for me now, but I don't understand why would it be dangerous (with a proper charger). And I mean in series. Connecting 11 pieces of 3.3V cells in series is 36.3V. Charging them with a balanced charger wouldn't be a problem. The A123 cells are LiFePO4.

Ah, I read your post to say you were considering a dozen of those pre-packaged packs which in series would be over 120v with a tremendous discharge capability (yikes)! I've run a homemade boombox with a small LiPo pack, which has very impressive run time, but I would never-ever leave it unattended and the battery goes right back into the fireproof storage bag. Ceramic pan with lid or Pyrex glass would be even better. Lots of stories in the r/c hobby about garages being burned down and autos destroyed from overcharging LiPo batteries or accidental shorts. Spectacular flames (as you can see in the video). LiFe are indeed safer, but still a short can cause a fire. Just be very very careful.

Lastly, neither of those types of batteries can handle complete discharge... they die if discharged all the way. It's easy to see when running an electric motor, but unless you have a good metering system, with audio you won't know until it's too late.

[Jack Caldwell]

Originally Posted by erozsolt

I think I won't invest in such a thing now, as it's a bit more expensive for me now, but I don't understand why would it be dangerous (with a proper charger). And I mean in series. Connecting 11 pieces of 3.3V cells in series is 36.3V. Charging them with a balanced charger wouldn't be a problem. The A123 cells are LiFePO4.

Hi, just a quick note about using LiFePo4 batteries with the 2050 type amps. They can work very well.

1) Some of these sound incredibly good, like the RedWine Audio Black Lightning LFP supplies. I have one of these and the difference between these and any SLA or any of the smps I've heard to date is stunning.

2) Note that LiFePo4 is NOT Lithium Ion and it is NOT explosive, do not confuse the two.

3) The one spec that is missing from a lot of LiFePo4 vendors is the internal or source resistance. The best I have seen on a 3.3V LiFePo4 cell is under 30 mili-Ohms, so when you get 8 of those in series for a 25.6V battery, the total DC source resistance is around 0.024 ohms or lower, which is very good indeed.

4) And while I have not yet seen any published graphs of source impedance vs frequency for LiFePo4 batteries, but Vinnie at RedWine told me that there are significant variations between batteries. The cells he gets as custom items are extremely low impedance at HF, much lower than SLA batteries and/or most linear or switching supplies. This is probably the key reason for his supplies sounding so much better. And, no, he isn't about to tell us which vendor he gets them from... curses! foiled again!

Just the same, it is probably a useful endeavor for the diy community to explore this topic in depth. Maybe we should start a battery-powered thread for Tripaths, if it doesn't already exist...

So, in my experience with LiFePo4, about the only thing that explodes is the dynamics of your sound system.