[Beefy]

*no longer relevant*

 

[BoilermakerFan]

Corrected original post.

 

[Beefy]

Well stock is actually 24VA, according to the BOM.

And it isn't to make me happy, just an observation

 

[Beefy]

*double post*

 

[BoilermakerFan]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif Well stock is actually 24VA, according to the BOM. And it isn't to make me happy, just an observation

Just giving you a hard time. My wall warts from Beezar are all 40VA or 50VA...

But it was a good catch. I forgot I'm in the MHM thread and I have made a lot of BOM changes to my build to support the high currents I will be running.

 

[BoogieWoogie]

What ??Sorry I dint get a word I'm not familiarize with electric terms and I'm not a DYT.
Its this amp

Would something this work ? Or I only would need this plug converter to europe format, I recall its 220V in Europe

 

[BoogieWoogie]

double post..

 

[BoilermakerFan]

Quote:

Originally Posted by BoogieWoogie /img/forum/go_quote.gif What ??Sorry I dint get a word I'm not familiarize with electric terms and I'm not a DYT. Its this amp Would something this work ? Or I only would need this plug converter to europa format

That's a Mini-MAX, it only has 1" heat sinks so you cannot push very high bias currents so even a 40VA wall wart is overkill. All you need is a 25-30VA wall wart with an output of 24Vac. Most have screw terminals so you can attach the wire that is terminated in te correct plug for the jack on the back of the Mini-MAX.

 

[tomb]

Just stick with the BOM (which I'll update soon, btw). You need something that provides 24VAC output (not negotiable) with at least a 1A current capability. You can actually go higher with the current, but not lower.

(Pay no attention to this section if you're not an experienced DIY-er.

)
Honestly, I haven't found over-voltage to be that much of an issue - perhaps a volt or two once the walwart is even lightly loaded, as opposed to no load.

In any event, the PS heat sink will handle it. The limiting point of heat is the center two DB sinks, not the PS sink.

EDIT: If it's a MiniMAX, BMF is correct (well, only 0.75A is required) - that's a less current intensive amp than a MOSFET-MAX - two different animals.

 

[BoilermakerFan]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif Just stick with the BOM (which I'll update soon, btw). You need something that provides 24VAC output (not negotiable) with at least a 1A current capability. You can actually go higher with the current, but not lower. (Pay no attention to this section if you're not an experienced DIY-er. ) Honestly, I haven't found over-voltage to be that much of an issue - perhaps a volt or two once the walwart is even lightly loaded, as opposed to no load. In any event, the PS heat sink will handle it. The limiting point of heat is the center two DB sinks, not the PS sink. EDIT: If it's a MiniMAX, BMF is correct (well, only 0.75A is required) - that's a less current intensive amp than a MOSFET-MAX - two different animals.

Venting the bottom of the enclosure under the middle DB and V-Reg heat sinks should really help cooling with the vent holes in the new PCB too.

I went back and seriously edited my original post Tom. Stepping up to big boy bias levels required 6 BOM changes and my build is too far deviated from the normal BOM, so I don't want to confuse new builders.

The main point of my original post is that there are some nice options if a builder wants dual voltage compatibility and is willing to give up the beautiful Hammond enclosure for a larger one that can accept a switchable 120/240V IEC power inlet and use a dual primary toroid.

 

[BoogieWoogie]

Could you link me something from amazon or ebay that will do the job ?

 

[Beefy]

Quote:

Originally Posted by tomb /img/forum/go_quote.gif Honestly, I haven't found over-voltage to be that much of an issue - perhaps a volt or two once the walwart is even lightly loaded, as opposed to no load.

I've used three different 24VA wallwarts in Australia and Canada, and not one of them has ever been under 27VAC with tubes hot and music playing. Maybe my line voltage is just always high......

 

[Beefy]

Quote:

Originally Posted by BoogieWoogie /img/forum/go_quote.gif Could you link me something from amazon or ebay that will do the job ?

Well this is the one I ended up with (but Nexxtech branded), because I bought it before I had my Canadian credit card: Enercell*™ Switchable 18/24V/1A AC Power Adapter - RadioShack.com

 

[BoilermakerFan]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif I've used three different 24VA wallwarts in Australia and Canada, and not one of them has ever been under 27VAC with tubes hot and music playing. Maybe my line voltage is just always high......

High line voltage is far more common than low voltage nowadays in most parts of the US. Utilities figured out they can deliver a lot more billable power (or meet increasing demand) to residences and industry without having to upgrade much of their infrastructure if they bump up the line voltages. So the HV and MV lines were all bumped 5%-10% and this trickles down to as much as 5% on the 240V lines in the US residential grid. I'm fortunate in that my local grid is tied to a university campus so my line voltage stays pretty much 120V-121V.

 

[BoogieWoogie]

Quote:

Originally Posted by Beefy /img/forum/go_quote.gif Well this is the one I ended up with (but Nexxtech branded), because I bought it before I had my Canadian credit card: Enercell*™ Switchable 18/24V/1A AC Power Adapter - RadioShack.com

So if I connect that to a 220v corrent it can deal with it ?