Try this slightly less technical and quite entertaining book High-Power Audio Amplifier Construction Manual
Or check out @danieljw YouTube series
This thread covers a bit of the 'origin' and design decisions made along the way.
Excellent will add that to my reading list - I already read Douglas Self on power amps, and starting Bob Cordell now.
Will also have a look at YouTube.
Dan,
When I raise the voltage starting from 0, where exactly should I be observing about 26 mA.....between TP107 and TP108? And should that be 26 mA or mV as the Build Guide test procedure appears to measure mV everywhere?
Also, R109 controls the output bias, correct? So if the resistance at R109 is set to maximum, there should be no output bias. Do I have that right?
John
When I raise the voltage starting from 0, where exactly should I be observing about 26 mA.....between TP107 and TP108? And should that be 26 mA or mV as the Build Guide test procedure appears to measure mV everywhere?
Also, R109 controls the output bias, correct? So if the resistance at R109 is set to maximum, there should be no output bias. Do I have that right?
John
Hi John,
I was referring to the current that will be displayed on your power supply with no output stage bias.
Your power supply itself should read 0.020A to 0.030A on its display before you set the bias.
Yes R109 sets bias, refer to the build guide as a reference but yes the pot needs to be set to its maximum resistance of 500 ohms between pins 1 and 2 before power up.
When you first turn your power supply on bring the voltage up slowly so you can make sure there is no major issue which may show up at low voltages.
I hope this is helpful
- Dan
I was referring to the current that will be displayed on your power supply with no output stage bias.
Your power supply itself should read 0.020A to 0.030A on its display before you set the bias.
Yes R109 sets bias, refer to the build guide as a reference but yes the pot needs to be set to its maximum resistance of 500 ohms between pins 1 and 2 before power up.
When you first turn your power supply on bring the voltage up slowly so you can make sure there is no major issue which may show up at low voltages.
I hope this is helpful
- Dan
Ok Dan, that is very helpful. Thanks for the clarification.
John
John
I just completed my test of one Wolverine channel (EF3-4 v. 4.0). To my great surprise nothing blew up and all the LEDs lit up when I reached 30 V. I wanted to run my readings past the team.
First, the output voltage settled at 758 mV and stayed there.
I was able to adjust R11 to achiev 5.0 V between TP-1 and TP-2.
I measured 591-593 mV between TP-3 and TP-4 which is bit lower than the 600-630. Is this ok?
Between TP-105 and the positive rail I measured 1.471 V. Between TP-106 and the negative rail I got 1.532 V. These measurements bother me because I used KSC3503 and KSA1381 for Q101 and Q102.....so I expected about 1.7 V. Is this ok?
DC offset was easily zeroed out. I could not measure AC voltage across TP100 and TP 104.
I was able adjust R109 to achieve output bias of 1.41 V. When I was done I returned R109 to maximum resistance.
I've tried to be as careful as I can with this build as I am a mere implementor. I could not have gotten this far without the help I've received from this build thread. I do appreciate it.
Let me know what you think about the couple of questionable readings.
John
First, the output voltage settled at 758 mV and stayed there.
I was able to adjust R11 to achiev 5.0 V between TP-1 and TP-2.
I measured 591-593 mV between TP-3 and TP-4 which is bit lower than the 600-630. Is this ok?
Between TP-105 and the positive rail I measured 1.471 V. Between TP-106 and the negative rail I got 1.532 V. These measurements bother me because I used KSC3503 and KSA1381 for Q101 and Q102.....so I expected about 1.7 V. Is this ok?
DC offset was easily zeroed out. I could not measure AC voltage across TP100 and TP 104.
I was able adjust R109 to achieve output bias of 1.41 V. When I was done I returned R109 to maximum resistance.
I've tried to be as careful as I can with this build as I am a mere implementor. I could not have gotten this far without the help I've received from this build thread. I do appreciate it.
Let me know what you think about the couple of questionable readings.
John
Attachments
Yes, all three jumpers are in place.
If everything is within tolerance, can I proceed to install the output transistors? J103 must be removed at this point. Does the 9.1K resistor in parallel with R17 stay in place while testing with the output transistors installed? Fuses go up to 2.0 A I suppose because of the larger current draw with the outputs installed. But we are stlll testing at 30 V per rail, right? What should current be limited to?
Thanks,
John
If everything is within tolerance, can I proceed to install the output transistors? J103 must be removed at this point. Does the 9.1K resistor in parallel with R17 stay in place while testing with the output transistors installed? Fuses go up to 2.0 A I suppose because of the larger current draw with the outputs installed. But we are stlll testing at 30 V per rail, right? What should current be limited to?
Thanks,
John
Hi John,
The rail fuses can stay at 2A for now, after power down and caps are discharged (see the rail leds extinguish slowly) J103 comes out and it is easy to remove by cutting each side with side cutters or desoldering.
The 9.1 kOhm resistor can stay for testing at low rails voltages with 30V rails.
Once your output transistors are in do your pre flight checks again, check slowly using the build guide.
Also once the output transistors are in make sure there is no electrical connection for the transistors metal back to the heatsink with the continuity beep function on your digital multimeter. Do not skip this step or else you will blow up your output transistors.
If in doubt post a question and I will do my best to help during these crucial steps.
Once you get to the biasing step you will slowly increase bias to 44mV using R109. Use a positive DMM probe clip on TP101 and negative dmm probe clip on on TP102. DMM set to mV
Expect about 400mA to 500mA on your power supply which will likely read very approximately 0.440A per channel. Expect your heatsink to slowly warm up. Take some time for it to be stable and re-adjust tp 44mV in small increments.
Please only make connections with you amp powered down and caps discharged for your safety.
Once again use the build guide and take your time to check off the steps, you are very close to success.
- Dan
The rail fuses can stay at 2A for now, after power down and caps are discharged (see the rail leds extinguish slowly) J103 comes out and it is easy to remove by cutting each side with side cutters or desoldering.
The 9.1 kOhm resistor can stay for testing at low rails voltages with 30V rails.
Once your output transistors are in do your pre flight checks again, check slowly using the build guide.
Also once the output transistors are in make sure there is no electrical connection for the transistors metal back to the heatsink with the continuity beep function on your digital multimeter. Do not skip this step or else you will blow up your output transistors.
If in doubt post a question and I will do my best to help during these crucial steps.
Once you get to the biasing step you will slowly increase bias to 44mV using R109. Use a positive DMM probe clip on TP101 and negative dmm probe clip on on TP102. DMM set to mV
Expect about 400mA to 500mA on your power supply which will likely read very approximately 0.440A per channel. Expect your heatsink to slowly warm up. Take some time for it to be stable and re-adjust tp 44mV in small increments.
Please only make connections with you amp powered down and caps discharged for your safety.
Once again use the build guide and take your time to check off the steps, you are very close to success.
- Dan
I think you mean the bias voltage across TP107 and TP108, all good.
yep 👍 This may get closer when at full rail voltage, not the 30V we testing with
yep 👍 This may get closer when at full rail voltage, not the 30V we testing with
--
All good to install output transistors as per Daniels instruction.
Yup, current limit at 600mA (0.6A) as we expect 350-500mA being drawn per channel when the bias is pulled up by turning R109 (not at first power up, because R109 is at max resistance and little to no current flows)
One other thing to note when you go to measure bias voltage (that isn't clear in the old build guide and has caught some people here before), when the output transistors are installed and J103 is removed - you are measuring bias voltage across TP101 and TP102 eyelets and NOT TP107 / TP108 which are no longer used, as they were before.
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Dan and Mainframe: very helpful information. For the initial test I used 0.5 A rail fuses. I will now switch to 2.0 A fuses. Dan has made a big point to check each leg of those output transistors to insure I am not shorted to the heat sink. I hear you loud and clear. Also, Mainframe's point about where to measure bias: I would totally have missed this without your comment.
Many thanks to both of you. I'll let you know how it goes.
John
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I want to extend my heartfelt thanks to @Mainframe for his incredible effort in updating the Wolverine Build Guide to support the V5 boards. His dedication and meticulous work have made a significant difference, ensuring that all V5 builders have a clear and comprehensive instructions tailored to the latest version.
The full version of the Build Guide is available to all who have signed up for the 5th Group Buy. It provides a detailed step-by-step procedures and safety information.
To give everyone a glimpse of the wealth of knowledge @Mainframe and others have contributed, he has extracted and shared the 'Wolverine PSU info' and 'Wolverine FAQ' sections from the complete guide. These sections alone offer invaluable insights into power supply options and common questions — perfect for both new and experienced builders. I have added these documents to the first post of this thread for easy access.
Additionally, I’d like to thank @danieljw for his efforts in testing, measurement and creating detailed results plots, which have been instrumental in demonstrating the exceptional performance of the Wolverine V5 design. I can honestly say that the V5 would not be what it is today without @danieljw unwavering commitment to testing and extracting every last bit of performance from the V5 boards.
Thanks to Charles’s updates, we now have a reliable reference that streamlines the build process, helps avoid pitfalls, and promotes safe operation, especially given the high voltages involved. His work not only clarifies the assembly steps but also inspires confidence in tackling this exceptional project.
Once again, thank you, @Mainframe and @danieljw, for your dedication. Your contributions greatly enhance our experience and ensure the high standards of the Wolverine project are maintained. I, along with others in the community, truly appreciate your time, expertise, and commitment.
The full version of the Build Guide is available to all who have signed up for the 5th Group Buy. It provides a detailed step-by-step procedures and safety information.
To give everyone a glimpse of the wealth of knowledge @Mainframe and others have contributed, he has extracted and shared the 'Wolverine PSU info' and 'Wolverine FAQ' sections from the complete guide. These sections alone offer invaluable insights into power supply options and common questions — perfect for both new and experienced builders. I have added these documents to the first post of this thread for easy access.
Additionally, I’d like to thank @danieljw for his efforts in testing, measurement and creating detailed results plots, which have been instrumental in demonstrating the exceptional performance of the Wolverine V5 design. I can honestly say that the V5 would not be what it is today without @danieljw unwavering commitment to testing and extracting every last bit of performance from the V5 boards.
Thanks to Charles’s updates, we now have a reliable reference that streamlines the build process, helps avoid pitfalls, and promotes safe operation, especially given the high voltages involved. His work not only clarifies the assembly steps but also inspires confidence in tackling this exceptional project.
Once again, thank you, @Mainframe and @danieljw, for your dedication. Your contributions greatly enhance our experience and ensure the high standards of the Wolverine project are maintained. I, along with others in the community, truly appreciate your time, expertise, and commitment.
I only built on the mammoth guide Stuart had started, which is easier to be fair. Hope everyone finds it helpful anyway 🙂 And the guide is now full of Daniel, Stuart and my test build pictures for assembly, thanks to the whole team, and Daniel for all the V5 testing.
The original guide was constructed by @neilshop and then added to and updated by entire Wolverine team over the years. 😎
Will be...
As soon as each members boards are shipped their Dropbox link to all the V5 documentation including build guide will be sent out.
I hope to place the order for the boards this weekend. 🥳
If you don't have a Dropbox account you may wish to register for one.
Don't worry it's free.
Any updates or additions to the documentation will be automatically added or updated and your link will never expire.