Hello all!
Finally got round to putting this together.
I’m getting 404 watts at 67 volts.
How much can I push it? I’ve got some very power hungry low sensitivity speakers I’m planning on driving.
Is 450 ish watts at 4 achievable?
Thanks
Finally got round to putting this together.
I’m getting 404 watts at 67 volts.
How much can I push it? I’ve got some very power hungry low sensitivity speakers I’m planning on driving.
Is 450 ish watts at 4 achievable?
Thanks
can you elaborate on your build? 3-pr or 4-pr version, what choices did you make on outputs? What is this testing done with, assume 4-ohm, but at what frequency, 1kHz? Not a lot of information to provide you feedback on you 450 watt goal.
Additionally - you won't be able to tell a difference at 400 vs 450 with your ears. Yes, you can measure it and brag about it, but you won't be able to "hear" a 50 watt difference listenting to music.
Additionally - you won't be able to tell a difference at 400 vs 450 with your ears. Yes, you can measure it and brag about it, but you won't be able to "hear" a 50 watt difference listenting to music.
Hi everyone,
I am in the process of building a Wolverine EF3-4:
I am interested in purchasing a MicroAudio Cobra-S2 Switched Mode Power Supply (SMPS) compatible with Wolverine EF3-4 with at least +/- 70 V rail voltage.
https://micro-audio.com/store/product/cobra-s2/
My first question is: how many SMPS's do I need for a stereo version of the Wolverine: 1 or 2? I was told by MicroAudio only 1.
I am a little confused which other voltages to choose:
Can anyone help me with that?
Do I need more filtering (PSU caps) after the SMPS?
Are there any significant drawbacks using an SMPS instead of a Linear PSU? E.g. I read something about more noise.
What are the advantages?
I am planning to include a soft-start board (although it seems this is not necessary with a well-designed SMPS), a speaker protector board and a ground-lift board, which all need their own power supply, and maybe I have to add something else I didn't think about now, in the future. It would be good not to have to add another small PSU inside the case for that.
Cheers,
Wouter
I am in the process of building a Wolverine EF3-4:
| Output | onsemi | MJL4281 | MJL4302 | TO-264 |
| Driver | sanken | 2SC4883A | 2SA1859A | TO-220 |
I am interested in purchasing a MicroAudio Cobra-S2 Switched Mode Power Supply (SMPS) compatible with Wolverine EF3-4 with at least +/- 70 V rail voltage.
https://micro-audio.com/store/product/cobra-s2/
My first question is: how many SMPS's do I need for a stereo version of the Wolverine: 1 or 2? I was told by MicroAudio only 1.
I am a little confused which other voltages to choose:
- AUX Voltage (Regulated) +/- 12 VDC, +/- 15 VDC or +/- 18 VDC;
- Driver voltage +/- 15 VDC (only choice);
- Standby power supply voltage + 5 VDC or + 12 VDC, both 3W.
Can anyone help me with that?
Do I need more filtering (PSU caps) after the SMPS?
Are there any significant drawbacks using an SMPS instead of a Linear PSU? E.g. I read something about more noise.
What are the advantages?
I am planning to include a soft-start board (although it seems this is not necessary with a well-designed SMPS), a speaker protector board and a ground-lift board, which all need their own power supply, and maybe I have to add something else I didn't think about now, in the future. It would be good not to have to add another small PSU inside the case for that.
Cheers,
Wouter
Hi Janusz, I found these terminals with seven different colour screws at DigiKey Australia:
This one is black:
8191-3
TERM SCREW 6-32 4 PIN PCB
Keystone Electronics
Datasheet: https://www.keyelco.com/userAssets/file/M65p66.pdf
Mouser Australia has them as well:
Mouser Part No
534-8191 (nickel)
Hope that helps.
Wouter
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Hello gents,...been a while...moved to a new home. This morning I did a full measurment with the inputs shorted. The Wolverine is my daily runner for both music and tv. It's switched on permanently. The longtail pair measured 5.1 volts on both sides. Made small adjustment. The offsets were spot on. bothe sides measured 0,00 volts. No adjustments needed and AC was 0,00 as well. The idle current on one side was 44 mV while on the other side it measured 40 mV. Made small adjustment here while waiting with the cover back on and she ready for the next year or so I guess.
cheers
Willem
cheers
Willem
Is there any BOM available to the general public, or do you have to get it through the group buy?
Thanks.
Thanks.
Group buy indeed .... This forum and thread are free ofcourse but meant for the buyers of the board and anything related to the board including the BOM🙂
1. Output and driver choice is good for 98% of speakers with +/-70V SMPS
2. Definitely only need 1x cobra for a stereo build - the 1200W Cobra can do 1900W peaks! (2x ~850)
3. Use +/-12V for AUX (regulated) - not used by wolverine - can be used for auxiliary boards like speaker protects or housekeeping boards.
Leave driver voltage as is - not used by wolverine - this is a class D amp thing typically
Standby power supply voltage I would recommend 12VDC - this will be used to power any speaker protection boards you might like to use - unless you specifically want to use a speaker protection that runs on 5VDC
4. No more filtering caps required after the SMPS (there may be some arguments against this, but very simply put - the SMPS is replenishing its internal smoothing caps at 65khz+ i.e. there is no way any music can successfully "deplete" the smoothing caps)
5. No proven drawbacks to a SMPS other than that of longevity. It is widely accepted a linear supply will outlast a SMPS when run at full power. If you place a SMPS too close to the input stage you can get down-modulated EMI/switching noise and also direct mains noise from its little transformer (it still has one!), similarly if you place a linear supply, either its transformers or rectifiers too close to the input stage you get mains and switching noise. Basically, keep the power supply away from the input stages. Advantages to SMPS are weight and in most cases cost (not so much audio power amp SMPS, as ultra clean dual rail massive SMPS are still quite niche). Cobra and some other SMPS also offer the advantage of containing a lot of the "housekeeping" circuits such as start button inputs, LED power state indicating outputs, trigger inputs (12V in from preamps or AVRS), etc. SMPS also
6. Shouldn't need a soft start board for any audio-based SMPS - AFAIK they all have a 'slow' ramp of the output rails about 3-500ms. Don't need an auxiliary PSU if you use the cobra for speaker protects - that's exactly what the "standby" and "auxiliary" rails are for. GND Lift doesn't need power, it's a passive device.
HTH.
Some more info
4 pr version tested with 1khz sine wave set to 4 ohm..
Using the MJL4281 / MJL4302 outputs
Huh? I have my current maximum output measured on the scope already as per my initial post.
My question is more specific to voltages, has anyone experimented with going slightly higher than 71 volts. My current PSU setup is pushing out 67 volts
My question is more specific to voltages, has anyone experimented with going slightly higher than 71 volts. My current PSU setup is pushing out 67 volts
Thanks very much Mainframe! I think I'll order one because they are on special.
Cheers, Wouter
@AvLee Oh, sorry, I misinterpreted your measurement setup. I don't know of anyone that's gone higher than 71V LPS (70V cobra SMPS would be the "stiffest" supply). I'd hazard a guess that a cobra SMPS at 70-71V would just hit 430W/4R at ~1-3% distortion.
What is the distortion setting you are getting your 404W at? is that 1%? But yeah, as others mention, at these power levels, you aren't going to notice the last 50W, clean or dirty.
What is the distortion setting you are getting your 404W at? is that 1%? But yeah, as others mention, at these power levels, you aren't going to notice the last 50W, clean or dirty.
Getting ready to install output transistors on my EF-3 build.
Page 44 of the build guide lists TO-3P mica, but I also have TO-220 mica - see photo.
I want to confirm the right part here as my last go at this stage of a new board burned out some transistors, likely from a imperfect output transistor installation. I have watched Daniel's video on installing the output transistors and feel I have a better understanding of the care needed to get this right.
So just confirming I should use the TO-3P mica vs. the TO-220 [they give better coverage over the entire transistors.]
Thanks
Page 44 of the build guide lists TO-3P mica, but I also have TO-220 mica - see photo.
I want to confirm the right part here as my last go at this stage of a new board burned out some transistors, likely from a imperfect output transistor installation. I have watched Daniel's video on installing the output transistors and feel I have a better understanding of the care needed to get this right.
So just confirming I should use the TO-3P mica vs. the TO-220 [they give better coverage over the entire transistors.]
Thanks
