Hi people,
I'm currently building my first solid state amp. I've built a fully active 7-channel 2.1-system with chipamps and it works great. I'm totally happy with it, and there is no need to change anything. Right now I should be on the ocean, saving the whales, or somewhere else curing beautiful daughters from virginity ... . But, you know ... .
I think these speakers will be under construction for a long time.
A few days ago a parcel from China arrived with PCB's for Cap Multipliers, TDA7293 parallel chipamps and a pretty simple mono MOSFET amp, I found while surfing the EasyEDA open source projects. At the moment the Subwoofer, a MIVOC AW 3000 in 50l sealed, is powered by two TDA7293 in parallel configuraton running at +/-32,5V and about 70000µF/rail. It goes deep, it's dynamic, I like it.
I just want to find out if this MOSFET Amp is maybe doing the job even better. I want to run it with a little higher voltage and I'm aiming for a 28-0-28V/ 500VA toroid.
This amp is not audiophile champions-league and I think, as a SW-amp it doesn't need to be. It just shall deliver buckets of current (also for the next chassis; the GRS SW12-4HE seems to offer a lot of "boom" for the buck).
Ok, now I got to order caps & MOSFETS, so I got a break and a few questions:
For VT6 I took a BD139 instead of a BD135. Is that ok?
R13 is marked with a star (?), as far as I know (I'm just a mechanic) is this the place for the BIAS adjustment. I couldn't find any description about this. Should I use a 1k trimmer instead of a 750R resistor, or shouldn't I care?
I added a Zobel with 10R/1W, 100nF at the output, ok?
IRFP9240 are hard to get, the 9140 should do the job, but there are two versions 9140 and 9140N. Which one should i choose?
Ok, thats it for now. Many thanks in advance for your patience with a newbie 😉 .
best regards
J.
I'm currently building my first solid state amp. I've built a fully active 7-channel 2.1-system with chipamps and it works great. I'm totally happy with it, and there is no need to change anything. Right now I should be on the ocean, saving the whales, or somewhere else curing beautiful daughters from virginity ... . But, you know ... .
I think these speakers will be under construction for a long time.
A few days ago a parcel from China arrived with PCB's for Cap Multipliers, TDA7293 parallel chipamps and a pretty simple mono MOSFET amp, I found while surfing the EasyEDA open source projects. At the moment the Subwoofer, a MIVOC AW 3000 in 50l sealed, is powered by two TDA7293 in parallel configuraton running at +/-32,5V and about 70000µF/rail. It goes deep, it's dynamic, I like it.
I just want to find out if this MOSFET Amp is maybe doing the job even better. I want to run it with a little higher voltage and I'm aiming for a 28-0-28V/ 500VA toroid.
This amp is not audiophile champions-league and I think, as a SW-amp it doesn't need to be. It just shall deliver buckets of current (also for the next chassis; the GRS SW12-4HE seems to offer a lot of "boom" for the buck).
Ok, now I got to order caps & MOSFETS, so I got a break and a few questions:
For VT6 I took a BD139 instead of a BD135. Is that ok?
R13 is marked with a star (?), as far as I know (I'm just a mechanic) is this the place for the BIAS adjustment. I couldn't find any description about this. Should I use a 1k trimmer instead of a 750R resistor, or shouldn't I care?
I added a Zobel with 10R/1W, 100nF at the output, ok?
IRFP9240 are hard to get, the 9140 should do the job, but there are two versions 9140 and 9140N. Which one should i choose?
Ok, thats it for now. Many thanks in advance for your patience with a newbie 😉 .
best regards
J.
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Hmm, I've got a very small bandwidth internet-access, so I cannot say for sure, if just I cannot see the attached schematic, or if it's missing for all. I'll attach it to this post, also. Hope you can see it.
