I don't understand that part of your calculation. You appear to be equating RMS current in speaker with RMS current in secondary. They are not the same thing.synonymous said:
If you mean continuous full level music then you need to double the transformer size. You need to be clear about this: a 250VA transformer cannot supply 250W DC continuously; a Class AB amp (even an ideal one) needs more than 250W DC in to produce 250W AC out.
The 80V CT transformer will allow some 200W into 4 ohms considering normal losses.
Using the 90V one will only increase losses and heat and in practice provide no more power.
Even not knowing your amp in detail, I go by Enzo´s immortal definition: "the amplifier is that thingie between power supply and speaker"
Using the 90V one will only increase losses and heat and in practice provide no more power.
Even not knowing your amp in detail, I go by Enzo´s immortal definition: "the amplifier is that thingie between power supply and speaker"
Unfortunately I can not. However my experience tells me to treat the 500W as peak, and derate it to 250W DC which is still more than the DC you can get from a 250VA coil.
I use one of these for a tube amp, and derate it accordingly. MINI DC-AC Inverter 12V to 18V220V/380V 500W Boost Step UP Power Module New Hot | eBay
Thanks for all the replies folks.
Sorry if I come across in ignorance and/or as an ***. It's why I'm here!
Here's a pic of what I am working on..
A Raspberry Pi powered amp. The DAC is not shown due to that it's designed to be replaceable, although one could be easily added to this mainboard. Power control for the amp via the Pi as well, only when needed with an off delay. This board is designed to fit snugly into a mini3u dissipante chassis from the diy store. Minimal wires and concealed beneath the board. The transformers are going to be mounted vertically against the faceplate for space conservation. I may have found a way to squeeze another 2mm of height to possibly fit the 330va trans inside. Dont ask.
Sorry if I come across in ignorance and/or as an ***. It's why I'm here!
Here's a pic of what I am working on..
A Raspberry Pi powered amp. The DAC is not shown due to that it's designed to be replaceable, although one could be easily added to this mainboard. Power control for the amp via the Pi as well, only when needed with an off delay. This board is designed to fit snugly into a mini3u dissipante chassis from the diy store. Minimal wires and concealed beneath the board. The transformers are going to be mounted vertically against the faceplate for space conservation. I may have found a way to squeeze another 2mm of height to possibly fit the 330va trans inside. Dont ask.
What else do you need to know?
Aught to be in spec for both Hitachi and Semelab Exicon devices, single or dual die.
Heatsinks @ recommended value for the 70v rail version similar to Rod Elliot project.
Aught to be in spec.
Numerous sources use 2 pairs @56v rails, and Rod Elliot recommends no more than 70v rails.
I have some leftover Hitachi 1058 162 that I intend to use initially, and if I make more than two of these I intend to use the double die matched devices from Exicon.
Thanks
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.