H
HAYK
I have designed many amplifiers where all the posted files sing in perfection, not to mention SET 300B/2A3C. Either you have wide band open loop or op amp type and 70db@20khz. The experience with your zero distortion amp shows there is no alternative. Bellow is an example of very low cost amp which got 70db@20khz and sings celestial voice.
Thank you for precising that Frank's voice sounds dirty with this amp, because I don't know exactly what causes this phenomena, now for sure it is not due to amp nonlinearities. There are many other voice that have such character, as Neil Diamond, young Barry manilow, Pavarotti.
If you can skip just a single sip of beer, buy from Ali this
https://www.aliexpress.com/item/100...!sea!TH!4284450371&curPageLogUid=VWH0Bfb0nz85
and modify it to ABD mod
https://www.diyaudio.com/community/...nto-abd-modulation.396664/page-4#post-7301714
and you have the highest resolution possible I know that will show you how the music file should sound like. I decided to end definitively analog amplifiers, as I cannot imagine what kind of analog amp I can design, all technologies confused, can reproduce such high level of resolution.
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Guys, please, this is the Wolverine build thread.
This thread is for people to discuss their builds, build issues, and parts for the DIY Class A/B "Wolverine" Power Amplifier as it says in the first post.
This thread is for people to discuss their builds, build issues, and parts for the DIY Class A/B "Wolverine" Power Amplifier as it says in the first post.
Just curious if any builders tried Sanken 2SC3284/2SA1303 in OPS?
2sc3284_ds_en.pdf
2sa1303_ds_en.pdf
2sc3284_ds_en.pdf
2sa1303_ds_en.pdf
I have a few sets of speakers that I randomly rotate in and out of the system, they range from easy 8R load to somewhat easy 4R load.
EF3-3 build with approx. 62V power supply, planning on using Toshiba 2SC4793/2SA1837 drivers. Still undecided which output transistors to go with
EF3-3 build with approx. 62V power supply, planning on using Toshiba 2SC4793/2SA1837 drivers. Still undecided which output transistors to go with
Hi, im about to order all the components and I´m not too sure about my choices.
NJW1302G/NJW3281G &
MJE15033G/MJE15032G &
Hypex SMPS1200A400 2x63Vdc
Are these good match? Some people recommend 2 toroidal transformers but smps are more "easy" way to go for me. But will it be noticeable difference using 2 toroidal PSU-s instead of SMPS?
NJW1302G/NJW3281G &
MJE15033G/MJE15032G &
Hypex SMPS1200A400 2x63Vdc
Are these good match? Some people recommend 2 toroidal transformers but smps are more "easy" way to go for me. But will it be noticeable difference using 2 toroidal PSU-s instead of SMPS?
I think you will be ok with those choices. It's like everything there is always tradeoffs. But you should have no concerns with a SMPS. I have not used the hypex ones but I can recommend Microaudio
My vote is almost always going to be big iron, well, ya know what I mean. I intend to do monos with the PS/s in their own enclosure. It's still gelling in the old melon, but the grin is already on my mug. 🙂 That is, if I can get one of the blue team to hook me up. 😉
For posterity, Ya'll remember this? 😱 Sorry about all the dust, but it's been on the shelve for the past couple. It was a project that I was rather proud of, so I left it there. We all spent a ton of time and money on it, for nothing other than wanted to give the DIY something truly special, and I think we did that. I was blessed to be a small part of it. 😉
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![20230327_184149[1].jpg](/community/data/attachments/1066/1066445-e97282218b4cc195ab97ae97930dee5f.jpg?hash=6XKCIYtMwZ)
I have a question about bias thermal compensation. When I install Q104 I measured the Hfe at 177 with ElCheapo tester, and so I chose the 68 ohm resistor for Rcc. As I play with the amp, it seems that perhaps the thermal compensation is too great. I am under the impression that the thermal compensation is intended to hold the voltage across the emitter resistors relatively constant over temperature, perhaps slightly over compensated for safety. My voltage definitely drops a lot as the output stage heats up. Q104 is mounted to a middle output transistor, MJL3581A. Voltage starts around 92mV at 15C, stabilizes at 43 around 35C at idle. I drive the temperature up to about 45C at 50W output with 49 volt rails. Turning off the signal, results in 23mV. The stage cools and goes back to the idle temp and bias in the 40 -44 range per the build guide. The temperature is measured with a thermocouple clipped to the heat sink in contact with the output transistor. I'm not sure that the absolute temperature is correct, as the cold junction is "simulated".
This is an EF3-4. It seems to me that the compensation slope is too high (absolute value). Should I increase the Rcc under the assumption that I have measured Q104 Hfe much higher than it is, or do I need to go the other way?
Thanks for whatever help the experts choose to give me.
This is an EF3-4. It seems to me that the compensation slope is too high (absolute value). Should I increase the Rcc under the assumption that I have measured Q104 Hfe much higher than it is, or do I need to go the other way?
Thanks for whatever help the experts choose to give me.
All those voltages seem normal to me, I am though suspicious of the 177 hfe measurement though. I have measured lots of mje340s and they are between 80 and 130.