Firebox - tube power amp emulator

[vigilante398]

Is this because they are redundant between the stages?

It's because when you get coupling caps around that size the difference in frequency response is minimal, so there won't be a big audible difference between values. I only use 100nF coupling caps because most of my customers are bassists so they're concerned about the response of super low frequencies.

 

[Chuck D. Bones]

Is this because they are redundant between the stages?

It's because 47nF is more than enough for coupling between stages.

Between 1st & 2nd stages, there is 220K in series with the coupling cap. Do the math, the corner freq is 16Hz.

Between 2nd & push-pull stages, there is a 1M pot more-or-less in series with the 47uF cap. Corner freq is = ? Let's not always see the same hands...

The 125A XFMR bandwidth is 150Hz - 15KHz, assuming you match the impedances correctly.

 

[temol]

Any progress on this?

 

[vigilante398]

Any progress on this?

*long drawn out sigh*

So I've had PCBs in hand for several weeks now, but I've just had so much going on that I haven't had made time to wire this up and try it out. I have the transformer on hand, I have an enclosure set aside for it, I think I'm missing a couple of the 2W resistors I was going to use though so I'll have to check and add them to my next order.

 

[Feral Feline]

So to reduce shipping costs on my Heater and Foxtrot, I should wait until the Firebox is fully ready...

 

[vigilante398]

So to reduce shipping costs on my Heater and Foxtrot, I should wait until the Firebox is fully ready...

I don't have immediate plans for a DIY version of Firebox as I would have to figure out how to easily mount the tubes without my obnoxious right angle daughter boards. I won't rule it out completely, but not a plan for the immediate future.

 

[Feral Feline]

@vigilante398 — I like your right-angle daughter boards. I hate tubes sticking out of enclosures a mile high waiting to be kicked/crushed.

 

[vigilante398]

@vigilante398 — I like your right-angle daughter boards. I hate tubes sticking out of enclosures a mile high waiting to be kicked/crushed.

They're cool, they're just a little obnoxious to assemble. Maybe sometime I'll post some pics of what the assembly process looks like and you can decide if you think it's worth the effort. They certainly make things easier from a layout perspective and free up a lot more room.

 

[Gordo]

Getting the damn things out....now that's another story

 

[temol]

bump...