Buyout switching supply

[blair]

http://www.parts-express.com/pe/showdetl.cfm?partnumber=129-147&utm_source=Retail&utm_medium=Email_Newsletter&utm_content=129-147&utm_campaign=email040413

This caught my eye with all the tube talk, etc.

The ripple looks pretty good for B+ though maybe a few thousand uf of capacitance may not hurt. The 7.5VDC can have a little series resistance added to drop the 1.2V for 6.3V filaments.

For $20, you could complete a tube preamp using only parts express parts for around 60-80 bucks. The 12AU7 will do OK at 50V, but the 6DJ8 or 6922 is much happier at that voltage.

Just fuel for folks that want to play with tubes, but not lethal voltages.

[donradick]

Re: Buyout switching supply

Yeah, I saw that - looks nice, in my case for a possible Class D amp setup.

[1100xxben]

Re: Buyout switching supply

Ummm, anyone else confused about the fact that it's only rated for 1.38A continuous output on +/- 54V, but it can supposedly deliver 445 watts continuous??

[johnnyrichards]

Re: Buyout switching supply

Ummm, anyone else confused about the fact that it's only rated for 1.38A continuous output on +/- 54V, but it can supposedly deliver 445 watts continuous??

Nope, just your basic no-frills advertising.

[fbov]

Re: Buyout switching supply

Before you discount their claims as advertising, you may want to consider the specs. In a dynamic application, the 5 minute spec applies, as their "continuous" spec would only apply to noise signals (constant RMS draw). 54V x 4A twice, for the two polarities, is consistent with the claim of 445W. It all depends how you define "continuous."

Have fun,
Frank

[Sidi]

Re: Buyout switching supply

These are thermally limited specs. hence 5mins 1min, etc. Put a much large heatsink on it and you could have a higher continuous operation. But you have to verify the junction temps in the switching fets or you could have a very limited lifespan.

Correction: those transformers also look a bit dinky, they also may limit where you can run it continuously. It'll take a full analysis to really find the full capability when modified.

[thekorvers]

Re: Buyout switching supply

It all depends how you define "continuous."

Have fun,
Frank

Continous power is well defined as are average power, RMS power, instantaneous power, etc.

Agreed that this power supply is claimed to be able to output 445 Watts for a period of 5 minutes.

[AJ]

Re: Buyout switching supply

Assuming the ratings are accurate, it could be useful for a class AB amp. I would use one per channel for 120W/8ohms and ok operation into 4ohms. You would want to filter the rails for the input and VAS stages, or create a separate low current, linear power supply for them. Provide the supplies with their own heatsinks and a fan running low speed to keep the case temp down...

[charlielaub]

Re: Buyout switching supply

These seem to be a perfect power supply for the IRAUDAMP based L-15D amp that is known to have good performance. The combination should be able to deliver [email protected], [email protected] music power. Here's a pic of the L-15D amp board:



These are available on Ebay for around $60 PER PAIR, including shipping:

http://www.ebay.com/itm/120687170518

There are many other sellers...

I just picked up a few of the power supplies, so thanks to Blair for posting about it!

-Charlie

[Thomas Brown]

Re: Buyout switching supply

If possible this is something I would like to discuss with you, possibly at the up-coming NorCal event, in lame-man's terms, as a possibility of me getting my feet wet with an amp build.

Or if some more details can be posted for others to see/contribute would be good

I'm guessing you would need 2 boards you listed, 1 PS?, a cap bank, inputs, outputs, softstart?, volume/gain pot?
Think it might be an inexpensive? way to get a feel for amp-first-timer.

These seem to be a perfect power supply for the IRAUDAMP based L-15D amp that is known to have good performance. The combination should be able to deliver [email protected], [email protected] music power. Here's a pic of the L-15D amp board:

[ATTACH=CONFIG]35204[/ATTACH]

These are available on Ebay for around $60 PER PAIR, including shipping:

http://www.ebay.com/itm/120687170518

There are many other sellers...

I just picked up a few of the power supplies, so thanks to Blair for posting about it!

-Charlie

[Whitneyville1]

Re: Buyout switching supply

Most good high mu tubes (the ones that make good AB output power tubes) like 300+ volts on their plates. The good 'ole 300C3 or 300C4 loves 600-800 VDC minimum on it's plates. The higher the voltage to arc-over, the greater the linear range. Those old "coke bottle" tubes put out some SERIOUS wattage. The price of your output transformer will be your limitation. Over on The Vinyl Engine, one of the guys is building a pair of mono-blocks with 4 300C3 each. He's using a French output tranny, $2400 a side.:eek:

[foxfire3]

Re: Buyout switching supply

These seem to be a perfect power supply for the IRAUDAMP based L-15D amp that is known to have good performance. The combination should be able to deliver [email protected], [email protected] music power. Here's a pic of the L-15D amp board:

[ATTACH=CONFIG]35204[/ATTACH]

These are available on Ebay for around $60 PER PAIR, including shipping:

http://www.ebay.com/itm/120687170518

There are many other sellers...

I just picked up a few of the power supplies, so thanks to Blair for posting about it!

-Charlie

Charlie, is the sound quality of the L-15D noticeably better than the LM3886 kits that are also on Ebay?
Some of the Class D stuff I've listened to sounds a little more "crisp" than I'm used to hearing with some of the older Class AB stuff.

[thekorvers]

Re: Buyout switching supply

If possible this is something I would like to discuss with you, possibly at the up-coming NorCal event, in lame-man's terms, as a possibility of me getting my feet wet with an amp build.

Or if some more details can be posted for others to see/contribute would be good

I'm guessing you would need 2 boards you listed, 1 PS?, a cap bank, inputs, outputs, softstart?, volume/gain pot?
Think it might be an inexpensive? way to get a feel for amp-first-timer.

1 PS per amp board. So 2 for 2 channels.

[blair]

Re: Buyout switching supply

Most good high mu tubes (the ones that make good AB output power tubes) like 300+ volts on their plates. The good 'ole 300C3 or 300C4 loves 600-800 VDC minimum on it's plates. The higher the voltage to arc-over, the greater the linear range. Those old "coke bottle" tubes put out some SERIOUS wattage. The price of your output transformer will be your limitation. Over on The Vinyl Engine, one of the guys is building a pair of mono-blocks with 4 300C3 each. He's using a French output tranny, $2400 a side.:eek:

Hi,

I started this as a preamp power supply option. I do not know of any power tubes that will do much with 50V. That's not true. You could use the negative rail for bias

I am also preparing to build a project with a pair of Sowter outputs that, in their day, were very expensive. I'm getting them for around $400, but with their current market price they would be around $1,400. I'm going to use 6-8 KT88s per side.

Blair

[bwaslo]

Re: Buyout switching supply

I picked up some of these yesterday. The suckers are really built, Norwegian designed and built. Fused three different ways, all kinds of protection circuits, compliance ratings, REGULATED output.. The "1.4A" issue I don't think is relevant unless you plan to drive a space heater with it. >4A for 5minutes, >15A for brief peaks. I really don't want 4A continuous going into my speaker for over 5minutes....that would probably indicate the amp was blown...


This is quite a bit heavier than a Meanwell supply.