Exactly......
A simple current mirror VAS and EF output stage will be exciting and diy freinds will love and have fun building this new APEX amp design (maybe with 4 pair for initial build using lower rail voltage then can be upgrade with few versions later into a max pairs accordingly) that will fit everyone needs.
Regards,
A simple current mirror VAS and EF output stage will be exciting and diy freinds will love and have fun building this new APEX amp design (maybe with 4 pair for initial build using lower rail voltage then can be upgrade with few versions later into a max pairs accordingly) that will fit everyone needs.
Regards,
SOA problem
You are right. There is a very clear SOA problem. See attached picture.
Simulations show 400W to 1000W resistive load @4R.
SOA worsens with real reactive load. 😕
You are right. There is a very clear SOA problem. See attached picture.
Simulations show 400W to 1000W resistive load @4R.
SOA worsens with real reactive load. 😕
Attachments
I use my usual Pmax guide.
Pmax ~ total BJT output stage wattage divide by 5 or 6.
Since the 1943/5200 have terrible high voltage SOA, I would use divide by 6 if I can keep them cool enough.
9pr of 150W devices = 2700W.
Pmax ~ 450W if kept adequately cooled.
That's why I raised the comment, particularly since Apex is suggesting it for PA duty.
Pmax ~ total BJT output stage wattage divide by 5 or 6.
Since the 1943/5200 have terrible high voltage SOA, I would use divide by 6 if I can keep them cool enough.
9pr of 150W devices = 2700W.
Pmax ~ 450W if kept adequately cooled.
That's why I raised the comment, particularly since Apex is suggesting it for PA duty.
BA1000 Input include: Balanced Input, 30Hz Low Cut Filter, Limiter and Volume Control,
Regards
Attachments
You can use this simple DC protection with 40A relay (12V for car)
Attachments
Last edited:
How many ampere transformer is needed and how it ac voltage, as well as how the value recommended of elco?
It is a reoccurring theme trying to use a Low Voltage DC contact rating ( 14VDC) to construct a Speaker protection circuit. 110VDC@40ADC with the suggested relay is impossible, and this is a benign scenario. View the accompanying graph of a typical Automotive relay contact capability before experimenting with welding techniques.
Attachments
Thanks for warning, I see 12V/80A relay in CREST CA18 and get this idea. I will try this relay with 220vac and 1500W heater for test 🙂
Attachments
Last edited:
1500VA, 2x75vac, 50A bridge rectifier, 4x 10 000uF/120V elcos for single channel.
This amp can't have 1000W at 8 Ohms +/-110V is maximum rail voltage, and this is low THD design.
the topology reminds me of the Pioneer Spec2 Power amps in the late 70's or early 80's.......😀 well regarded and still fetches about $2000 in Epay...
rails idled at +-91volts....rated at over 200 watts into 8 ohms or 4 ohms, at 4 ohms a lower ac voltage is chosen to protect the output trannies...