Jetstream 75A PSU

crosstownk

Hi,

I'm looking for a high current 13.8VDC power supply to power a high end car stereo in my house.

I came across this.

Has anyone here any experience or view on this product.

All feedback appreciated.

Xantia

It must be some stereo!
What is the current requirement for the stereo?

crosstownk

Xantia wrote: »

It must be some stereo!
What is the current requirement for the stereo?

Average consumption would be estimated to be 50A from component specs but it could peak a bit higher. Max could be around 70A but that would be momentary. I've never measured it.

Xantia

Are you sure? it sounds way over the top
It would not be a stereo that would run in a car so.

That power supply would be expensive as you would have to bring it in from USA with weight and customs etc.

crosstownk

Xantia wrote: »

Are you sure? it sounds way over the top
It would not be a stereo that would run in a car so.

That power supply would be expensive as you would have to bring it in from USA with weight and customs etc.

Yep. It'll cost around €300 shipped from the US. Then whatever Revenue will want.

The system is a 3 amplifier system. I removed it from the car over the weekend so now need to power it indoors.

martinedwards

50A?

good grief I'm glad I don't live within 5 miles of you.

that's PA level of volume!!

crosstownk

martinedwards wrote: »

50A?

good grief I'm glad I don't live within 5 miles of you.

that's PA level of volume!!

It's not really that bad. Each amplifier amplifies a dedicated part of the overall spectrum. However, it is quite loud when needed.

I'm about to order the PSU. Any thoughts on its performance?

dxhound2005

A few reviews here from radio amateurs. Bit mixed.

http://www.eham.net/reviews/detail/8498

watty

Mad to buy something so heavy from USA, Mad to get something so expensive outside EU, and most of all very risky to buy USA Domestic Products (115V vs 230V and 60Hz vs 50Hz, different electrical safety schemes)

Buying EU you get 2 year warranty. Any warranty from USA will be less and with the shipping cost back essentially worthless.

I do buy small stuff from USA and often stuff from Asia. But I wouldn't by this from U.S.

A 13.8V PSU isn't rocket science. There are plenty of them sold at 200W+ rating for Amateur Radio "Shack use". But frankly much more than 15A for a single appliance @ 13.6V is a bit mad. Wiring issues. Maybe better to use a PSU for each amp.

But also 13.8V powered Amps are a horrible design compromise at high power 50A compared to mains based same power 2.5A. You'd want about 40V to 50V single ended or 20V to 25V bridged for decent HT rail for output transistors at the sorts of powers you want.

Fuzzy Clam

crosstownk wrote: »

It's not really that bad. Each amplifier amplifies a dedicated part of the overall spectrum. However, it is quite loud when needed.

I'm about to order the PSU. Any thoughts on its performance?

Is 50 Amps the total for all the amplifiers?

If not, what is the requirement per amp?

I know of a modular supply than can supply 2*12v @ 20 amps and 1*12v @ 40 A.

crosstownk

Yes. 50A would be a total. 1x 25A, 1x20A, 1x6.5A (OK - so that's 51.5A ). Then there is also the head unit and DSP/Crossover that would probably draw another few but they could be powered by a smaller supply.

I'd rather use a 13.8V supply which is a better approximation of the voltage in a car with the alternator spinning. The equipment I'm using gives it's max output at 14.4VDC. The power supply mentioned above is adjustable so I could increase the voltage to 14.4V if needed.

watty

Yes you are correct, most gear designed for cars used to assume 13.8 (traditional Lead Acid on charge from Alternator) and modern "Calcium" Technology AKA zero maintenance Lead Acid sit at 14.2V on trickle charge fully charged. 12V is a bit low.

Use 3 off 13.8V PSUs sold for Amateur Radio / Illegal Italian CB in Italy.

Likely cheap from Italy as they are notorious for lack of enforcement and massive power on CB and even more massive on Amateur bands!

€44 for 25A and about €61 for 30A, so buy 2 x 25A and one 10A
http://www.ebay.it/itm/Hype-ALIMENTATORE-POWERHOUSE-25A-13-8v-per-caricabatterie-Cod-082-6022-/290741560312

Search EU with desired settings on ebay.ie (i.e. All European Union, Lowest Price first)
Then edit the .ie to .co.uk
then .de
then .it

Searching EU or Worldwide, Italy is cheapest for 25A BUT I DIDN'T CHECK SHIPPING.

Note that outside EU as it's heavy, bulky and more than €20 INC SHIPPING, you have to pay VAT + €6 to customs. As a minimum.

crosstownk

Cheers, Watty. Thanks for the info.

watty

Note I can't recommend any particular unit. But if from an EU supplier you do have 2 years Warranty FROM THE SELLER, irrespective of what their sales conditions say and any Maker's Warranty is in addition, not a replacement.

Wotty

Have you a link to the relevant legislation?

If so I may be able to claim a warranty repair / replacement of an electrical item bought from a retailer in Ireland.

Why are more people not aware of this important law? I certainly wasn't.

Wotty

Astron make some teriffic power supplies, have a look at their range to see if anything suits. Note, that these are switch mode units rather than linear power supplies.

watty

SOGA = Sale of Goods Act.

Apple got fined in Italy for selling Warranties within the SOGA period.

Retailers will routinely deny any such law exists. Search.

Durable items MUST be as described / advertised at time of sale and fit for purpose and are expected only to be fit for purpose if they last over 2 years. Liability can extend to 6 years.

Only proof of purchase is required. You do not need packaging. It's up to retailer if they repair or replace or refund. A Credit note isn't a refund.