I'm looking for solder by numbers power amp plans either point to point or with simple to etch pcb plans.
Some where in the 200-250W per channel into 8 ohm range.
Easily sourced and cheap components. I'm planning to build 6 channels for outdoor PA, so something reliable please.
SPL is more important than SQ. These are for Subs and mid bass.
Thanks in advance.
Some where in the 200-250W per channel into 8 ohm range.
Easily sourced and cheap components. I'm planning to build 6 channels for outdoor PA, so something reliable please.
SPL is more important than SQ. These are for Subs and mid bass.
Thanks in advance.
I attached audio amplifier diagram below.
For more details, read this topic (use google translate):
FET300 - un amplificator audio simplu si performant - DIY & Kituri Electronice - Comunitatea Tehnium Azi
For more details, read this topic (use google translate):
FET300 - un amplificator audio simplu si performant - DIY & Kituri Electronice - Comunitatea Tehnium Azi
Look at the TI National LME39810 (BJT) and LME39830 (FET) driver IC datasheets. Probably available from TI but I got my datasheets through the local farnell.com website (they stock them). One IC, 2 pass transistors, a circuit breaker, transformer, diode bridge, and two filter caps, 14 other parts, you're done. Some guy on Solid State forum is puffing a PWB kit he is selling for the FET version.
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It's nearly always cheaper to buy second-hand amps than build from scratch. Plus, name-brand amps have protection circuits and resale value.
Power Level - 500VA
Note that just one 500VA toroid power transformer from Plitron is about $160 (plus shipping). Figure on another $100 for a case, $100 for heat sinks, $100 for filter caps. Now a used Peavey CS800 or PV8.5C from the music store looks like a bargain. Check eBay for power amps within pickup distance; if you can avoid shipping, you have an advantage over other potential bidders. Try local sound rental companies; some of them must be replacing their heavy old amps with lightweight class-D amps and selling off the old iron.
Power Level - 500VA
Note that just one 500VA toroid power transformer from Plitron is about $160 (plus shipping). Figure on another $100 for a case, $100 for heat sinks, $100 for filter caps. Now a used Peavey CS800 or PV8.5C from the music store looks like a bargain. Check eBay for power amps within pickup distance; if you can avoid shipping, you have an advantage over other potential bidders. Try local sound rental companies; some of them must be replacing their heavy old amps with lightweight class-D amps and selling off the old iron.
sir i triad to access to site True link you gave us. but i can't download non of the PDF document you attach there. could you help me to get that top & bottom pcb lay out & construction detail in English. i am new to diy sorry for bad English
thanks
nuwan
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Please don't post links to other forums where one needs to be a member to view images or attachments. It's not fair to members of this forum.http://www.circuitstoday.com/wp-content/uploads/2008/03/150-watt-amplifer-circuit.png
Any comments on this one?
Any comments on this one?
Yes, they've drawn the circuit inside out
.Well, simple it most certainly is, and distort it most certainly will. But unfortunately they've not drawn the biggest, heaviest and most expensive part of the circuit; the power supply. Not that that will be sophisticated for an amp like this; a transformer (a bit higher than 30-0-30), a massive bridge rectifier and lots of capacitance at 63 volts. But do you want all this amplification together, or distributed? It might be quite a lot cheaper, and certainly no heavier, to get a single 2000 watt transformer than six (or even three) smaller ones.
You could, either by paralleling up an extra pair of output transistors (and associated emitter resistors) and thus driving a lower impedance, or by bridging up (and thus doubling the available voltage) and doubling the output transistors, get quite a bit more power out of this circuit - depending ultimately on what you can get as a power transformer.
Wanders off grumbling about "pure class B, zero standing current, no RF stabilisation, no Zobel network, crossover distortion…" and fades out into the distance.
Where are you that no-one's trying to dispose of older, heavy amplifiers and replace them with modern ones that may not last quite as long as the older style butgive you a decent risk of getting old without being crippled by the transport? Do they have component s
Yes, they've drawn the circuit inside out
Well, simple it most certainly is, and distort it most certainly will. But unfortunately they've not drawn the biggest, heaviest and most expensive part of the circuit; the power supply. Not that that will be sophisticated for an amp like this; a transformer (a bit higher than 30-0-30), a massive bridge rectifier and lots of capacitance at 63 volts. But do you want all this amplification together, or distributed? It might be quite a lot cheaper, and certainly no heavier, to get a single 2000 watt transformer than six (or even three) smaller ones.
Multiple amps give me scalability and redundancy. If one section breaks down, a quick reconfigure and I'm back up and running but at reduced power. Where I am there are many electrical rewinding shops. Sourcing transformers isn't my problem.
It appears that the circuit as posted is thermally very unstable. Pity because it is cheap and powerful. I'm imagining TIP142/147 or TIP2955/3055 as output because they are available everywhere and cheap. Nice simple multiple pair designs with PCB's would be useful.
Would class B MOSFET's be too nasty?
I'm in Cebu, used amps just don't get sold for reasonable prices. There are a few component shops but fakes are rife. Post is not really an option here, many packages go missing.
It's quite frustrating, there are so many excellent threads that head in the right direction, just as a PCB is about to be finalized, somebody comes along and suggests a modification that improves the SQ by 0.01% but adds complexity and exotic components.
On this site the Apex designs look good, I love the Destroyer amps. Quasi, has some great stuff but there aren't any "build" threads that don't spiral off and end up being impossible to follow, the APEX thread for example bounces between many threads, and it is very difficult to understand, even which amps are being referred to. Destroyer and Quasi are similar.
Do I really need to get out the books and reinvent the wheel, just to be able to take part in the conversation?
I'm not technically savvy enough to troubleshoot a new project, and it seems although there is a need for simple cheap designs, they don't seem to be well documented.
I've built some ESP projects, I've etched some of my own boards, I've built Arduino based projects, but DIY audio power amps don't seem to have solid accessible designs.
I'm sure there are many others out there that need a little handholding, to try and enjoy the hobby.
(Sorry, if this seems like a rant, it isn't meant to be one.)
theb0b - what components are available to you, in the areas of signal transistors (low power, high gain), driver transistors (medium power, medium gain), and output transistors (high power, gain low unless Darlington)?
Are signal / power / Zener diodes easy enough to obtain?
Perhaps with the help of people here, a design could be created or adapted that gets reasonable performance from the components available in your area (I'm in NZ, so am spoiled for choice, but still have plenty of standard old parts in my junk boxes).
I whipped up the CircuitsToday design in LTspice, with appropriate models from OnSemi, and I can concurr with chrispenycate - it's pretty crud. On the other hand, turning it into a usable amplifier would be a good learning experience - a few minor mods improves performance significantly, such as swapping out the bootstrap for a proper current source, and adding in a Vbe multiplier to take it from pure class B to class AB.
Are signal / power / Zener diodes easy enough to obtain?
Perhaps with the help of people here, a design could be created or adapted that gets reasonable performance from the components available in your area (I'm in NZ, so am spoiled for choice, but still have plenty of standard old parts in my junk boxes).
I whipped up the CircuitsToday design in LTspice, with appropriate models from OnSemi, and I can concurr with chrispenycate - it's pretty crud. On the other hand, turning it into a usable amplifier would be a good learning experience - a few minor mods improves performance significantly, such as swapping out the bootstrap for a proper current source, and adding in a Vbe multiplier to take it from pure class B to class AB.
dear gajanan phadte,
i also want to make an out door hi fi amplifier with soft start,short circuit protector,with mosfet or bipolar that are easily available in india.i have two 40watts 12 inch speaker that was given by my friend.i will etch pcb.plz give me sugession and hint.thanking you.yours masood
Yeah! I've done the P3a and it isn't really powerful enough for what I need.
I've sourced all of the actives for a few Destroyer DHR Turbo's. The PCB design is for 7 pairs, but trimming off the outside 2 I think I can make a 5 pair prototype first.
I'll be using 2N5401/2N5551 for the IPS, 2SC4793 for the VAS, 2SC4793/2SA1837 for drivers and 2SC5200/2SA1943 for outputs. And I've got the Zener's.
I'll be using a pair of +28-0-28 V transformers about 10 amps each.
I haven't got enough 100V Caps for the PS yet, but I've got all the others, I'm just hoping that the 100V rating is not fake. Unfortunately my resistors are only 5% so I'm going to have to check them all.
For a heat sink I'm planning on using a cylinder head from an old 2stroke Suzuki!
I'm going to be using the board design by alex mm, I can't find the post it is in in the This is DHR thread, but I saved it somewhere.
Audio Amateur reprinted plans for a PA amp that would do about 550W into 4 ohms; I think the plans may be reprinted in the book, "Audio Amateur Power Amp Projects". Unfortunately, it was designed around the classic and discontinued Hitachi MOSFETs, but there may be substitutes by now. The plans included a board for thermal and DC offset protection.
The ETI 466 amp may be worth considering. ETI-466 Amplifier Technical Review
Another possibility: use chipamps bridged and paralleled. The LM3886 is about as cheap as a single power transistor.
The ETI 466 amp may be worth considering. ETI-466 Amplifier Technical Review
Another possibility: use chipamps bridged and paralleled. The LM3886 is about as cheap as a single power transistor.
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