hello apex sir which apex amplifier model gives more details in music & songs hearing for Hi End speakers... i am very much intrested in your amps
try AX-11 and is pretty detailed in sound 😀 don't mind about my ugly set up I care for good sound 🙂 and also there is a lot of options to chose from mister Willie has many layouts styles to chose from too. sorry the question was directed to mister Miles 😛
best regards
Juan
best regards
Juan
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The frequency response of the amplifier is perhaps suffering from problems of your sound card, too many high-frequency oscillations, however the bass response is normal, otherwise I think there is a problem in the feedback loop of your amplifier 🙂
Thank you, rafsky. It's an experiment, check. Doing different amplifiers APEX. Very good sound🙂.
No!!!
Next year first i have to buildt a speaker protection unit!
May be in 2015...
🙂
Regards Olaf
Hi apex,
I have made nx14 using IRFP460 . sound is very good and clean. Thanks for providing such nice a circuit 🙂. Do u have any circuit which only uses N channel FET and can provide 300w to 500w at 4ohm load?
I have made nx14 using IRFP460 . sound is very good and clean. Thanks for providing such nice a circuit 🙂. Do u have any circuit which only uses N channel FET and can provide 300w to 500w at 4ohm load?
Sorry it was only a test setup with unregulated power supply so I disassemble the circuit 😱. But i will definitely post pictures when i complete my amplifier.
Apex, can i parallel 5 pairs of FETs to get 500w on 4ohm load using NX14 circuit ? then what should be DC supply voltage ?
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Mr Mile
Is it best to use 2x24Vac transformer or is a 2x18Vac transformer OK regarding this preamp regulator circuit
Thanks
AX20
Hi mr Mile ! I took so long but here I am like a snail walking 🙂... with my first AX20 channel and NE555 protection, clip led, signal led and power led, in same pcb. Everything is working perfect, power supply +55VDC – 55VDC, DC ofset – 2,5mv. I changed C9 and C10 to 33pF to avoid visible oscilations, I replaced R16 to 1K5 to get enougf bias, 15mv across R33/5W. Is it normal to get 3,54V across colector/emiter of BD139? This amplifier sounds veeeeeeery good, sine wave is perfect, but when I use dummy 8R square wave, you can see the diference betwen with 1uF in paralel or without, is this normal ? In scope, you see 1KHz and 5V per div. I dont have over shooting obssesion anyway 🙂... Output sine Wave 1KHz without clip: 8R 32VAC, 128W, 4R 30VAC, 225W. About supply for NE555 (12VAC) protection, what should I do ? Should I put a smal transformer for it, or get 12VAC from a special winding to the main transformer that I have to order. Thanks a lot Mile !!!!!!!!
Pozdrav
Hi mr Mile ! I took so long but here I am like a snail walking 🙂... with my first AX20 channel and NE555 protection, clip led, signal led and power led, in same pcb. Everything is working perfect, power supply +55VDC – 55VDC, DC ofset – 2,5mv. I changed C9 and C10 to 33pF to avoid visible oscilations, I replaced R16 to 1K5 to get enougf bias, 15mv across R33/5W. Is it normal to get 3,54V across colector/emiter of BD139? This amplifier sounds veeeeeeery good, sine wave is perfect, but when I use dummy 8R square wave, you can see the diference betwen with 1uF in paralel or without, is this normal ? In scope, you see 1KHz and 5V per div. I dont have over shooting obssesion anyway 🙂... Output sine Wave 1KHz without clip: 8R 32VAC, 128W, 4R 30VAC, 225W. About supply for NE555 (12VAC) protection, what should I do ? Should I put a smal transformer for it, or get 12VAC from a special winding to the main transformer that I have to order. Thanks a lot Mile !!!!!!!!
Pozdrav
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Nice work... 12VAC supply for NE555 you can get from special winding to the main transformer.
Regards