Honey Badger Build... where to start?

I bought the following from the DIY Audio store today.


1 Mezmerize B1 Buffer 1 Universal Power Supply 1 Soft Start & Speaker Turn-On Delay / DC Protector Combo 1 The diyAB "Honey Badger" Class AB Power Amp - 150W/Channel

Not even sure if all these boards can be used together. Should I incorporate them all into one chasis, is the preamp ment to be standalone with it's own chasis power supply?

The more I read up on each, and all of the choices people have when building them, the more confusion arises. This is seems like it's going to get expensive pretty quickly ;) haha.

I plan to mostly use this amp with 8 ohm speakers, don't think I'll need the full 150 watts RMS per channel. Most likely just some decent 2 way speakers.

Do I really need 8 10ku filter caps and a massive 800va transformer with 45-0-45? Can I even use the universal power supply with this amp?

Are there any common alternatives to the chassis, maybe some asian sourced chassis at a reasonable price?

Thanks in advance for any tips from others who have had and found answers to the same questions.

Regards,

Mike Drz
 
Hmm, still no responses from the experts. :confused: I'd suggest beginning with the Honey Badger build guide which should be good (AFAIK). You are right that the threads can be confusing with people discussing many aspects in excruciating (and conflicting) detail, but again, build guide should be good. Once you review that, you may want to ask more specific questions. I've never built a Honey Badger but have looked at the thread from time to time.
 
Thanks guys, I think I'll build the amp first and hold off on the parts for the power supply. I can use a lab supply for testing purposes, but I won't have a proper heatsink to really run the amp full out. I found some cheaper chassis' in the diy store, just have to see how much shipping to Canada is with taxes brokerage etc.
 
build well under way

I pretty much soldered all resistors to my PCB, a few questions I have.



There is a diode on the board that is labeled "D-BC" optional; there's no mention of it in the build guide or on the BOM?



For the bias heatsinks, where do you guys source the thin aluminum?



Also for the fast connector male components, there are bent tabs that don't fit in the middle hole, is this just a through-hole that's not meant to be populated?



Thanks for any help, may put up pictures soon enough.
 
Hi mikedrz,


The d-bc is the diode Baker clamp. This diode is the BAV21, and the good Ostripper did write about this d-bc :


"Any 200v+ PRV (peak reverse voltage) , low reverse leakage in the nA range.
There are a lot of choices."



BTW the 1N4148 is not suitable.


Best regards


rephil




Thanks Rephil, if I'm not using this option, do I leave it empty or do I have to jumper wire it? There is over 200 pages in OS's build guide thread, most of it is just people arguing or giving alternate ideas. It's hard to find anything on there.
 
Download and read the Build guide here a few times. Most of your answers will be found there.

The diyAB "Honey Badger" Class AB Power Amp - 150W/Channel – diyAudio Store


Hi AudioSan, it's not in there. I've downloaded and printed out the build guide. It doesn't say anything about the d-bc, or where to source the thin aluminum for the VAS heat sink. I was asking because maybe somebody can recommend where they got their metal from etc. Maybe like a big box store, and what use they are usually sold for etc.
 
. It doesn't say anything about where to source the thin aluminum for the VAS heat sink. I was asking because maybe somebody can recommend where they got their metal from etc. Maybe like a big box store, and what use they are usually sold for etc.
I pick up aluminum screens on garbage day. Saw out 1/2", drill a #33 hole (for 4-40 screw) instant heat sink. Suitable for VAS, drivers, which often on commercial products don't have one, and also often burn up.
You can also buy TO220 TO126 heat sinks from distributors for about $1 if you have an order going to pay the $12 freight bill.
Home store HD has 1/16" aluminum angle, but the minimum length is usually 4'. After drilling #33 hole in aluminum file the burr off, that inhibits heat flow. Use safety glasses using power tools.
I was going to say, don't skimp on the heat sink for the output transistors, not even in the beginning. 2sc5200 are about $4 each and you do not want to over stress them. First cut for short tests you can use the window frame again to bridge 5 transistors, but for more than a few minutes you need something <1.5 degC/W. If you use the minimum dimension tool at newark/digikey you can find something odd sized on sale for <$30. Don't forget heat sink compound.
I use metal file cabinets for small amp projects. About $4 at the charity resale shop. After it works you can upgrade to something impressive and prof if it is worth it.
No advice on the honey badger, it doesn't match the no center tap transformers I find for $$. PCB is too long to fit the cases I retrofit, too. Center tap amps can burn your speaker to scrap in an instant, and my best speakers cost $400 each used. $700 new. Read protection threads, those boards are as complicated as the amp, and might work sometimes. Speaker caps work every time, but not suitable for dual supply amps.
 
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Thanks Rephil, if I'm not using this option, do I leave it empty or do I have to jumper wire it? There is over 200 pages in OS's build guide thread, most of it is just people arguing or giving alternate ideas. It's hard to find anything on there.



Hi mikedrz,


Look at the tracks on the PCB in order to see where they connect from the BAV21. I would not connect the base of Q9 to the collector of Q10 with a wire. The BAV21 is cheap and easily found. Put a BAV21.


You should read the 200 Pages and copy what you find interesting in Word in order to get it available to you when needed. BTW, there is also diyAB Amp - "The Honey Badger" to read ...


Best regards


rephil
 
I pick up aluminum screens on garbage day. Saw out 1/2", drill a #33 hole (for 4-40 screw) instant heat sink. Suitable for VAS, drivers, which often on commercial products don't have one, and also often burn up.
You can also buy TO220 TO126 heat sinks from distributors for about $1 if you have an order going to pay the $12 freight bill.
Home store HD has 1/16" aluminum angle, but the minimum length is usually 4'. After drilling #33 hole in aluminum file the burr off, that inhibits heat flow. Use safety glasses using power tools.
I was going to say, don't skimp on the heat sink for the output transistors, not even in the beginning. 2sc5200 are about $4 each and you do not want to over stress them. First cut for short tests you can use the window frame again to bridge 5 transistors, but for more than a few minutes you need something <1.5 degC/W. If you use the minimum dimension tool at newark/digikey you can find something odd sized on sale for <$30. Don't forget heat sink compound.
I use metal file cabinets for small amp projects. About $4 at the charity resale shop. After it works you can upgrade to something impressive and prof if it is worth it.
No advice on the honey badger, it doesn't match the no center tap transformers I find for $$. PCB is too long to fit the cases I retrofit, too. Center tap amps can burn your speaker to scrap in an instant, and my best speakers cost $400 each used. $700 new. Read protection threads, those boards are as complicated as the amp, and might work sometimes. Speaker caps work every time, but not suitable for dual supply amps.

Thanks, this is very useful. I have a piece of angle stock from Ikea furniture, but I think it's painted steel and it's kind of thick. People here usually through away microwaves, haven't come across screens. I can also drop by home depot to see if they have aluminum stock. I have a nice beefy HS for the output transistors, it cost quite a bit. I'll use it as a test heatsink, trying not to drill holes in it so that it can be used for other things in the future.
 
Hi mikedrz,


Look at the tracks on the PCB in order to see where they connect from the BAV21. I would not connect the base of Q9 to the collector of Q10 with a wire. The BAV21 is cheap and easily found. Put a BAV21.


You should read the 200 Pages and copy what you find interesting in Word in order to get it available to you when needed. BTW, there is also diyAB Amp - "The Honey Badger" to read ...


Best regards


rephil
Thanks, there's a lot of stuff in those threads, I have come across some info once, that I can't find. I didn't save it because I thought it'd all be included in the build guide. If it's not busy at work today, I'll try skim through the hundreds of pages. lol
 
Hi mikedrz,


Look at the tracks on the PCB in order to see where they connect from the BAV21. I would not connect the base of Q9 to the collector of Q10 with a wire. The BAV21 is cheap and easily found. Put a BAV21.


You should read the 200 Pages and copy what you find interesting in Word in order to get it available to you when needed. BTW, there is also diyAB Amp - "The Honey Badger" to read ...


Best regards

rephil

Hi rephil, what about your Honey Badger?
Did you manage to start the project?
Best Regards.
Thimios
 

AudioSan

Member
2009-02-12 7:47 pm
Hi AudioSan, it's not in there. I've downloaded and printed out the build guide. It doesn't say anything about the d-bc, or where to source the thin aluminum for the VAS heat sink. I was asking because maybe somebody can recommend where they got their metal from etc. Maybe like a big box store, and what use they are usually sold for etc.

I used some 2mm angled aluminium i had in storage (it had to be angled in my case).
Regarding PSU. You would be okei with 500-600VA 2x35Vac-2x40Vac and 8x10.000uf for a stereo amp.
I used a 1000VA 2x40Vac and 180.000uF capbank for my honey badger. But that's a 5ch amp.
 
Hi rephil, what about your Honey Badger?
Did you manage to start the project?
Best Regards.
Thimios


Hi Thimios :),


I did populate the two boards of my Honey Badger, this measuring all the components in order to get two PCBs having the components measuring both the same.


I have bought for the Honey Badger a Toroydi transformer 600VA 35Vac-0-35Vac that don't hum and has no difference in voltage between the two output. The ones I did buy some time ago at TME, the INDEL they did sell, have sadly :( these problems.


I have had some problems with my old spekarers the KEF Reference three (bought in the 199x) and so I have had the need to substitute them with more recent ones. I did choose nice loudspeakers from Canton in Germany where I did hear and bought them very recently. They sound great :D, much better than my old Kef ! Much progress has been done from the time they did produce the Kef I have in England.


Have a very nice day and great satisfactions in your builds my friend !


Best regards


rephil
 
You certainly can add speaker caps to a dual-rail amp if you want, no reason other than cost to stop you.
Line to line polar electrolytic caps, as 10000 uf+10000 uf, in speaker output sound funny at low wattage. My base listening level is 1/8 W- 1.4 Vpp. Try it on top octave solo piano, as Peter Nero Young & Warm & Wonderful Secret Love track. Requires hearing good to 14 khz to detect IMD artifacts.
4700 uf polyprophylene film cap would be the size of a 2x tall 19" relay rack chassis. Would cost $500 too.
Speaker return to negative rail to allow single polar electrolytic cap might drive most circuits crazy. teifbassue recommends cutting the transformer center tap and doubling rail cap voltage, to do this. $$ There might need to be a DC feedback circuit added to keep the old center of the amp in the middle of the two rails.
Most "protection" circuits sold have small AC rated contact relays to break DC arcs of maybe 1000 A. Sure recipe for contact welding. Serious proven hard contact relays from amp manufacturers like Peavey & Crown cost $50. Mosfet "relays" of 40 A capability are getting down there- The $80 one with screw terminals for 12 ga wire is not in stock today @ newark but the $220 one is. Michael Bean dual nfet disconnect is doable point to point, but reliability is not proven by market - nfets will short drain to source in some circumstances.
BTW I can see many single solder joint failures (as made by us amateurs) causing DC on speaker. Ultrasonic oscillation is mainly a design issue, IMHO, to be sorted out in checkout. So on new builds should check with throwaway speakers until lack of oscillation is proved. Many commercial speaker disconnect circuits do not have an ultrasonic detector. My Peavey's don't.
 
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AudioSan

Member
2009-02-12 7:47 pm
8 x 10mF (aka 10,000µF) is vast overkill for any amp driving 8 ohms from 45V. 10 to 15mF is plenty unless you are very tight for voltage headroom, in which case the 45V is the issue!

Let us know know you calculated that one. As it is totaly against allmost everything else. Even a class D amp at this level would like 40.000 uf or more.
What determins what you need. And what to look for. tell us the secret.
the one who made this amp says 20.000uF pr rail pr ch is optimum (as a guide). you say 2500uF pr rail pr ch. that would be about 2A ripple current.