Hello to anyone that reads this hope you are doing well. I currently have discovered upon DIY audio after being interested in getting my own audiophile setup. I would like to first state my objectives:
Obviously I do not know what my future speakers specs are but I can give you a basic rundown of the space the setup will be in.
The turntable will be a Technics SL-1200 MK2 which is currently being shipped (going to be a bit of a fixer up,er). Tomorrow I am building a flexy rack to put all of these future components (my mediocre gear will go on it for now).
Hoping this thread will provide some answers for other people like me as I couldn't really find a thread with what I was looking for.
So to cut a long story short I will get to the point with a few questions.
Kind Regards,
Sgt.Elias.
Edit: I didn't know which sub-forum to post this in, please let me know if it's in the wrong place and I'll move it.
- To build a complete DIY system (Pre-Amp) (Amp) (Speakers) (Extras such as DAC, EQ's Meters).
- Low - mid but flexible budget system which will out perform the non DIY systems at my desired price point.
- Gain a basic understanding of how each of my (future) audio components work.
- Not an audiophile but I do appreciate high quality stuff, and enjoy having nice things.
Obviously I do not know what my future speakers specs are but I can give you a basic rundown of the space the setup will be in.
- 11.ft x 13.ft room (however on one of the walls there is a wardrobe sticking out about 2 and a half feet spanning 3/4 of the wall so really the room is 11 x 10.5.ft) also as it is my bedroom I have a double bed sticking out in the middle of the room. This means that I don't have a proper listening space which is sad but I'll just have to make due and wait till I can afford to move out (I am 18).
The turntable will be a Technics SL-1200 MK2 which is currently being shipped (going to be a bit of a fixer up,er). Tomorrow I am building a flexy rack to put all of these future components (my mediocre gear will go on it for now).
Hoping this thread will provide some answers for other people like me as I couldn't really find a thread with what I was looking for.
So to cut a long story short I will get to the point with a few questions.
- Class D vs Class A/B for amp?
- If you think I should go for Class D or Class A/B what are some designs / products I should look into?
- What Pre-Amp designs should I look into?
- Budget for Amp is MAX £450
- Kits are preferred but don't mind sourcing individually
- Have some experience with through hole soldering, and have a decent soldering station, but very basic knowledge of electronics theory.
- Ask me any questions you need to to help you, help me.
Kind Regards,
Sgt.Elias.
Edit: I didn't know which sub-forum to post this in, please let me know if it's in the wrong place and I'll move it.
It seems you're asking about a lot in one post, but here's a few websites that may help you get some good ideas.
Elliott Sound Products, has lots of articles and projects:
https://sound-au.com/index.html
Two speaker driver distributors that have kits available:
https://www.parts-express.com/
https://www.madisoundspeakerstore.com/welcome
Elliott Sound Products, has lots of articles and projects:
https://sound-au.com/index.html
Two speaker driver distributors that have kits available:
https://www.parts-express.com/
https://www.madisoundspeakerstore.com/welcome
Thank you for taking the time reply, yeah sorry about that although I am mainly interested in amps at this moment as shown in the questions. I did come across Elliott Sound Products but I couldn't find any BOMs or tutorials (am I right in saying you get those when you buy the pcbs?). Project 101 interests me as I have read some good things about it online (although I can't work out whether it's class A, B or AB). Also the High Quality Audio Preamp project 88 interests me. Going to have to look into them a bit more.
If I read between the lines, I understand that you need a "turnkey" and well-documented amp kit, I don't know any more in class AB, you will certainly find more in class D.
Nowadays it is almost not useful to have a preamp, a source selector with a well-selected potentiometer is enough, and of course an RIAA preamp for your turntable.
It goes without saying that you will have other opinions, stay focused on your basic idea, don't let yourself be drawn into an adventure that is beyond your skills.
Nowadays it is almost not useful to have a preamp, a source selector with a well-selected potentiometer is enough, and of course an RIAA preamp for your turntable.
It goes without saying that you will have other opinions, stay focused on your basic idea, don't let yourself be drawn into an adventure that is beyond your skills.
I have my doubts about class D amps and magnetic phono cartridges for LP. I've picked up digital howl from FCC compliant labeled equipment with my cartridge, and keep the computer etc in a different room on a different circuit than the turntable.
Biggest bang for the buck is a good speaker. I find a full range like the visaton BG17-8 on the end of a 175 mm x 175 mm x 350 mm box with a 25 mm square hole in the back sounds better than most of the packaged garbage 2 ways I pick up at the charity resale shop. Or if you go out early on garbage day, projection TV's have good coaxial 7" drivers sitting on the curb waiting for a harvester.
Amp: Ron Elliot is instructive & sells PCB's but he only sells class AB speaker burners. IE amps that if one solder joint pops loose, the entire power supply dumps through the output transistor through the speaker coil. I prefer for starters capacitor coupled 50-70 w/ch amps like the Armstrong 621, or the modern version the Apex AX6. Somethng goes wrong, a $3 speaker capacitor takes the DC and is under no strain. These amps are single supply, but a split supply transformer can have the 2 windings connected series to achieve 30-55 AC volts ( transformer rating) or 50 to 70 vdc (rectified peak voltage). I built my Apex AX6 point to point with wire on bare board, but there are PCBs (that wouldn't fit my chassis) artworks on the first and last of the forum topic. My post with a list of transistors I used on the schematic on page 42 that this link comes up to: https://www.diyaudio.com/forums/solid-state/236256-retro-amp-50w-single-supply-42.html This amp is low enough distortion to listen to it with SP2(2004) speakers. Since it has no CCS for lower wire count, AX6 works best with a regulated power supply. I regulated 72 VDC open circuit to 69 vdc with a 72 v zener stack and 5 parallel TIP147 transistors on a heat sink. 2200 uf pre reg, 3300 uf afterwards for both channels, two 3300 uf speaker caps.
Preamp - I used to have a dynaco PAS2 preamp that was a classic, but a burglar took it 2020. Instead of 100 watts for vacuum tubes, I found a RA-88a disco mixer for $15 that uses 5 watts with op amps. Sold by both herald electronics & Olson radio. Hissy, hummy, but I tamed it by pulling the AC transformer out of the case, supplying it with 18 VDC from a wall transformer, and changing the op amps from 4558 to 33078 which killed the hiss. I had to install local rail bypass caps to the op amps and kill the RF gain with 33 pf across the feedback resistors on the RIAA amps (50X gain) but it is quiet, accurate. The advantage of a mixer, the turntable, CD, and FM radio volume can be left up all the time, I don't have to walk around to switch the input on the preamp, just power on the device I am going to listen to now.
So anyway, I think you can come up with a decent system for $200 instead of L450 for just the amp. Then you can spend more money on LP's or CD's, I bought one LP today for $29, they are not cheap anymore new.
The best bargain in cases, power supplies, controls, connectors etc, are blown up bar PA amps. I recommend the Peavey M-2600 or PV-4c or PV-8.5c as candidates for rebuilding. CS800x sounds good & has great speaker protection but is a little big for home use. There are CS600 and CS400 out there, I think they are late model with the low distortion 4580 or 4560 op amps on input. Bar bands blow up a lot of output transistors because they set up & tear down every night, and the wiring gets messed up shorting the amp. Get them quick before they are gone, class AB is going the way of the dodo bird, and Class D is IMHO not easily repairable by amateurs. The language on craigslist or gumtree is "PA amp for parts or repair".
Happy shopping & maybe building.
Biggest bang for the buck is a good speaker. I find a full range like the visaton BG17-8 on the end of a 175 mm x 175 mm x 350 mm box with a 25 mm square hole in the back sounds better than most of the packaged garbage 2 ways I pick up at the charity resale shop. Or if you go out early on garbage day, projection TV's have good coaxial 7" drivers sitting on the curb waiting for a harvester.
Amp: Ron Elliot is instructive & sells PCB's but he only sells class AB speaker burners. IE amps that if one solder joint pops loose, the entire power supply dumps through the output transistor through the speaker coil. I prefer for starters capacitor coupled 50-70 w/ch amps like the Armstrong 621, or the modern version the Apex AX6. Somethng goes wrong, a $3 speaker capacitor takes the DC and is under no strain. These amps are single supply, but a split supply transformer can have the 2 windings connected series to achieve 30-55 AC volts ( transformer rating) or 50 to 70 vdc (rectified peak voltage). I built my Apex AX6 point to point with wire on bare board, but there are PCBs (that wouldn't fit my chassis) artworks on the first and last of the forum topic. My post with a list of transistors I used on the schematic on page 42 that this link comes up to: https://www.diyaudio.com/forums/solid-state/236256-retro-amp-50w-single-supply-42.html This amp is low enough distortion to listen to it with SP2(2004) speakers. Since it has no CCS for lower wire count, AX6 works best with a regulated power supply. I regulated 72 VDC open circuit to 69 vdc with a 72 v zener stack and 5 parallel TIP147 transistors on a heat sink. 2200 uf pre reg, 3300 uf afterwards for both channels, two 3300 uf speaker caps.
Preamp - I used to have a dynaco PAS2 preamp that was a classic, but a burglar took it 2020. Instead of 100 watts for vacuum tubes, I found a RA-88a disco mixer for $15 that uses 5 watts with op amps. Sold by both herald electronics & Olson radio. Hissy, hummy, but I tamed it by pulling the AC transformer out of the case, supplying it with 18 VDC from a wall transformer, and changing the op amps from 4558 to 33078 which killed the hiss. I had to install local rail bypass caps to the op amps and kill the RF gain with 33 pf across the feedback resistors on the RIAA amps (50X gain) but it is quiet, accurate. The advantage of a mixer, the turntable, CD, and FM radio volume can be left up all the time, I don't have to walk around to switch the input on the preamp, just power on the device I am going to listen to now.
So anyway, I think you can come up with a decent system for $200 instead of L450 for just the amp. Then you can spend more money on LP's or CD's, I bought one LP today for $29, they are not cheap anymore new.
The best bargain in cases, power supplies, controls, connectors etc, are blown up bar PA amps. I recommend the Peavey M-2600 or PV-4c or PV-8.5c as candidates for rebuilding. CS800x sounds good & has great speaker protection but is a little big for home use. There are CS600 and CS400 out there, I think they are late model with the low distortion 4580 or 4560 op amps on input. Bar bands blow up a lot of output transistors because they set up & tear down every night, and the wiring gets messed up shorting the amp. Get them quick before they are gone, class AB is going the way of the dodo bird, and Class D is IMHO not easily repairable by amateurs. The language on craigslist or gumtree is "PA amp for parts or repair".
Happy shopping & maybe building.
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Hey Sgt.Elias, welcome to the forum. Wish I started with diy at your age. My diy journey started in 2016 with pretty much the same goals or vision as you, with zero experience and little knowledge. My first build was a simple point-to-point tube headphone amp. But this forum and its members has helped me to build my own hifi system, which I would like to think is audiophile quality now. Everything in my system is diy - DAC, preamp, amp, speakers, and sub. It took me many years and many different builds to get where I am now.
Getting back to your question. From my experience I would say that starting with a good set of speakers, you will appreciate every new component, upgrade or improvement in your system. But here are some nice projects to consider. Some are available in kit form.
Preamps:
Class A Power amps:
Class A/B amps:
Class D amps:
I have limited experience here, but can truly recommend this kit, but will require smd soldering which is easy to master: Transformer-fed TDA8932 25W/8R mono amp kits (Vendor’s Bazaar Forum)
Full Range Speakers:
Multi-Way speakers – other members can advise here, but probably better to start with a kit. I’m a full range man and fan.
You are welcome to send me a PM for more specific details or guidance.
Getting back to your question. From my experience I would say that starting with a good set of speakers, you will appreciate every new component, upgrade or improvement in your system. But here are some nice projects to consider. Some are available in kit form.
Preamps:
- Wayne's Burning Amp 2018 Linestage (diyAudio Store).
- B1 Buffer (no gain), but a very worthy upgrade is the Zen Mod Iron Pre (6, or 12dB gain) preamp. I have built a few preamps, but the Iron Pre is on another level.
Class A Power amps:
- ACA Mini low powered amp for sensitive speakers (diyAudio Store)
- M2X (Pass Labs forum)
- Any Nelson Pass amp like the Aleph J, F5, F6, F4, ...
Class A/B amps:
- The diyAB "Honey Badger" Class AB Power Amp - 150W/Channel (diyAudio Store)
- FH9HVX - Budget Conscious 100w Class AB for Lean Times (Group Buys Forum)
- so many other options. Other members can make more recommendations.
Class D amps:
I have limited experience here, but can truly recommend this kit, but will require smd soldering which is easy to master: Transformer-fed TDA8932 25W/8R mono amp kits (Vendor’s Bazaar Forum)
Full Range Speakers:
- TABAQs, which are easy builds but sound truly amazing.
- Frugal Horns of which there are 3 different sizes.
- too many other options to mention.
Multi-Way speakers – other members can advise here, but probably better to start with a kit. I’m a full range man and fan.
You are welcome to send me a PM for more specific details or guidance.
I would advice for you to focus first on one thing, make your speakers first, or your amplifier etc..
If you go all directions at once, you will not complete your project..
Troels gravesen has good turnkey kits for speakers, i can recommend kits using discovery drivers.
Preamplifier:
Using passive is solid choise as preamplifier, also you can get cheaply very good tube options these days. (if you like smooth sound)
nobsound e6, it is cheap i have it and i like it. You can modify it very easily to gain even better sound..
From Dr John cheap tube blog:
"Douk E6 This belongs to the above section but due to the epic nature of this comparison I give the Douk E6 its own subheading. I borrowed one of Andy's many units. It has the stock Chinese tubes, with O-Rings for damping. The caps had been changed to red Audiophiler MKP 250V 1.0 uF (marked 105J). These look similar to the ones I used. PS was a small 5V USB Charger. vs Yamamoto As well as I know the E6, I was still astonished by the sound. The most significant change is a larger sound field with fleshier images (befitting a DHT) and even more air. This is consistent with my experience but now the comparison is with a preamp whose second-hand price is 20 times the cost. One interesting observation is that the clicks and pops and LP artifacts are particularly highlighted. I think this is a result of the incredible high frequency extension, the high gain and transient speed. The Yamamoto is perhaps more controlled with large scaled music and its midrange (with the WE tubes) and rhythm a little more layered. But the E6 held its own for sure and I only continue to use the Yamamoto for the better connectivity. Note that this is the first time I have compared an E6 to estimable preamps (though my HK and NYC circles have, all to the same remarkable conclusion of equality, if not superiority). Remarkable!"
Amplifiers:
Good class D is abraxalito users: TDA8932 class d amplifier
This can be ordered as "Turnkey" kit ready soldered, it is also cheap and good sounding.
(replace 2 0,68uf caps with good quality filmcaps, it should be magnificent)
https://www.diyaudio.com/community/threads/transformer-fed-tda8932-25w-8r-mono-amp-kits.359193/
If you want good class ab poweramplifier kit almost "turnkey" you can order A60 ready built amplifier pcb from ebay/aliexpress.
Read this thread:
https://www.diyaudio.com/community/threads/a60-amplifier-build-this.368256/
There are first timers who built that on as their first amplifier.
If you go all directions at once, you will not complete your project..
Troels gravesen has good turnkey kits for speakers, i can recommend kits using discovery drivers.
Preamplifier:
Using passive is solid choise as preamplifier, also you can get cheaply very good tube options these days. (if you like smooth sound)
nobsound e6, it is cheap i have it and i like it. You can modify it very easily to gain even better sound..
From Dr John cheap tube blog:
"Douk E6 This belongs to the above section but due to the epic nature of this comparison I give the Douk E6 its own subheading. I borrowed one of Andy's many units. It has the stock Chinese tubes, with O-Rings for damping. The caps had been changed to red Audiophiler MKP 250V 1.0 uF (marked 105J). These look similar to the ones I used. PS was a small 5V USB Charger. vs Yamamoto As well as I know the E6, I was still astonished by the sound. The most significant change is a larger sound field with fleshier images (befitting a DHT) and even more air. This is consistent with my experience but now the comparison is with a preamp whose second-hand price is 20 times the cost. One interesting observation is that the clicks and pops and LP artifacts are particularly highlighted. I think this is a result of the incredible high frequency extension, the high gain and transient speed. The Yamamoto is perhaps more controlled with large scaled music and its midrange (with the WE tubes) and rhythm a little more layered. But the E6 held its own for sure and I only continue to use the Yamamoto for the better connectivity. Note that this is the first time I have compared an E6 to estimable preamps (though my HK and NYC circles have, all to the same remarkable conclusion of equality, if not superiority). Remarkable!"
Amplifiers:
Good class D is abraxalito users: TDA8932 class d amplifier
This can be ordered as "Turnkey" kit ready soldered, it is also cheap and good sounding.
(replace 2 0,68uf caps with good quality filmcaps, it should be magnificent)
https://www.diyaudio.com/community/threads/transformer-fed-tda8932-25w-8r-mono-amp-kits.359193/
If you want good class ab poweramplifier kit almost "turnkey" you can order A60 ready built amplifier pcb from ebay/aliexpress.
Read this thread:
https://www.diyaudio.com/community/threads/a60-amplifier-build-this.368256/
There are first timers who built that on as their first amplifier.
Nail on the head, will look into some class D amps and the other components you suggested. Thanks for the advice.
Cheers!
I will be honest, a lot of what you said I don't understand as it is a bit out of my depth but I will look into the peavey amps you recommended and if there are any resources for repairing / rebuilding them.
Cheers!
This is the kind of the answer I was looking for! Going to research some of your suggestions to see if any of them fit the bill. As for speakers go I don't have much space to put them, so they would have to be bookshelf speaker size (my idea is to put them on top of some vinyl storage boxes like the ikea kalax 1x2 (I'm pretty sure this is a terrible idea). Will reach out if I ever need to, thank you.
Cheers!
I Thank you also for the input, going to look into each of your suggestions. Maybe I will start on the speakers first as like twocent said I will be able to appreciate every upgrade even more.
Cheers!
I don't know if this link can be posted here, but why not this one, for example?
https://www.lf-pro.net/mbittner/Sym5_Webpage/symasym5_3.html
All necessary information for construction is available. The main thing is that interested person can make this amplifier himself from start to finish based on information there - if he dares, it is even possible to make circuit board himself.
I made it sometime around 2008-2009, good sounding amp and quite cheap.
Or why not widely discussed Apex amps? A33 and A40 are also not bad at all. And all that information and necessary support to build one, has already been worked out repeatedly here on the forum some time ago.
https://www.lf-pro.net/mbittner/Sym5_Webpage/symasym5_3.html
All necessary information for construction is available. The main thing is that interested person can make this amplifier himself from start to finish based on information there - if he dares, it is even possible to make circuit board himself.
I made it sometime around 2008-2009, good sounding amp and quite cheap.
Or why not widely discussed Apex amps? A33 and A40 are also not bad at all. And all that information and necessary support to build one, has already been worked out repeatedly here on the forum some time ago.
First of all, I think you need to get a taste of good sound and yet not bother yourself with complex difficult designs, you should try to build one of two simplest but high quality amplifiers, and understand the difference between the sound texture they produce. Then you can probably start building something more serious. These two amps to try:
1) JLH1969, class A old design, but sounds very good, very easy to build 1 day or 2 at most (I never built it though 🙂). A bit of a toy though, but it is a discrete design, which would teach how to deal with setting up idle currents, influence of transistor types on sound etc.
2) Something based on LM3886, just find a good PCB. This was my first DIY amp I've built, and it sounded awesome, very nice non-fatiguing sound, very neutral. A true real HI-FI chip. Hard to obtain originals these days though.
Both are good enough to be benchmark points for your future project. If it sounds worse than LM3886, than it is not worth using for everyday listening, no matter how low are distortions and how complex is the design of that amp.
1) JLH1969, class A old design, but sounds very good, very easy to build 1 day or 2 at most (I never built it though 🙂). A bit of a toy though, but it is a discrete design, which would teach how to deal with setting up idle currents, influence of transistor types on sound etc.
2) Something based on LM3886, just find a good PCB. This was my first DIY amp I've built, and it sounded awesome, very nice non-fatiguing sound, very neutral. A true real HI-FI chip. Hard to obtain originals these days though.
Both are good enough to be benchmark points for your future project. If it sounds worse than LM3886, than it is not worth using for everyday listening, no matter how low are distortions and how complex is the design of that amp.
If you want best sound for your money you should buy newer model commercial active monitor speakers. Like JBL or something.
Diy is not for saving money or fidelity. In that case you will only need a riia of which there are many great ones in the analog line? subforum. You could consider a battery powered since powersupply is the most complicated and expensive to get right.
A bit similar to indianajo i found a broken Denon amp, pulled all out except its funktioning powersupply, put in 2 amp board from AliExpress so now I have a great amp for 50 dollars. That was only partly diy of course.
Cheers
Diy is not for saving money or fidelity. In that case you will only need a riia of which there are many great ones in the analog line? subforum. You could consider a battery powered since powersupply is the most complicated and expensive to get right.
A bit similar to indianajo i found a broken Denon amp, pulled all out except its funktioning powersupply, put in 2 amp board from AliExpress so now I have a great amp for 50 dollars. That was only partly diy of course.
Cheers
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These are all A/B suggestions:
I really enjoy Rod Elliotts P3A amp and am powering it with.. gasp.... a SMPS so it fits in a pretty small case.
I have also built his P101 but it is currently waiting on a case before I really start listening to it.
Yes, once you buy you get access to the build guides with the BOMs. It can be challenging finding all the components now but sometimes that is part of the fun.
If you want a bit warmer sound then AmpsLabs LM60Mk2 is nice and comes as a kit with all the components.
I have an earlier version of the AmpsLab TDA7293Mod that pops some on turn on, I don't know with it being several versions later now, if he has changed that, but worth asking him. This kit has the advantage over the prior two listed as it doesn't have any bias or offset setting requirements. My version sounds quite good, I'd imagine several versions newer should sound as good or better.
The Ampslab ones are available with all the components, which can be very handy.
Class A can be fun but only if you are willing to commit to limiting speaker choices to higher efficiency (real efficiency, not just made up numbers from the manufactures so be aware that some will lie by 9dB or more, cough, Klipsch, cough.)
For speakers if you want to build from scratch I'd be tempted by:
https://www.diyaudio.com/community/threads/mark-ks-er18dxt.157595/
I've used the ER18RNX in Zaph's SR71 and would think the combination with that tweeter would be quite nice.
If you want a flatpack for the speaker boxes, I'm not sure what kit to recommend.
I really enjoy Rod Elliotts P3A amp and am powering it with.. gasp.... a SMPS so it fits in a pretty small case.
I have also built his P101 but it is currently waiting on a case before I really start listening to it.
Yes, once you buy you get access to the build guides with the BOMs. It can be challenging finding all the components now but sometimes that is part of the fun.
If you want a bit warmer sound then AmpsLabs LM60Mk2 is nice and comes as a kit with all the components.
I have an earlier version of the AmpsLab TDA7293Mod that pops some on turn on, I don't know with it being several versions later now, if he has changed that, but worth asking him. This kit has the advantage over the prior two listed as it doesn't have any bias or offset setting requirements. My version sounds quite good, I'd imagine several versions newer should sound as good or better.
The Ampslab ones are available with all the components, which can be very handy.
Class A can be fun but only if you are willing to commit to limiting speaker choices to higher efficiency (real efficiency, not just made up numbers from the manufactures so be aware that some will lie by 9dB or more, cough, Klipsch, cough.)
For speakers if you want to build from scratch I'd be tempted by:
https://www.diyaudio.com/community/threads/mark-ks-er18dxt.157595/
I've used the ER18RNX in Zaph's SR71 and would think the combination with that tweeter would be quite nice.
If you want a flatpack for the speaker boxes, I'm not sure what kit to recommend.
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Yes. those 2SK1058 2SJ162 were wonderful while they lasted. Out of production by Hitachi for years. Somewhat different exelon (2 dies instead of one) transistors have been sold in Europe, Allfet ALF08p16v and ALF08N16v have been on the market, claim to be lateral fets, I know of no one that has said anything nice about them.
Same with LM3886 IC amp in a previous post. Have been out of stock for about a year. Rumored from TI to come back but you had better be important to score them when they do hit the distributors. There is a single supply (speaker cap) version on the datasheet but I have never seen a PCB designed for that. Same with LM1875 IC amp, all PCBs available were split supply speaker burners when I was looking them up. There are DC protection boards all over the internet, but 99.999% use a cheap AC rated relay to break a DC arc when an output transistor fails.
I have 98 db 1w1m speakers (very sensitive), listen at 1/8 watt a lot of the time, but like 50 watts available when the orchestra reaches a crescendo peak. I view class A 10 watt amps as toys, like my Mother's RCA stereo that had half a 12AX7 tube as the speaker driver.
The Peavey amps I quoted for rebuild have schematics available, pretty complete parts list, a semiconductor peavey # to industry # list floating around. Crown has some good PA amps but there are strange parts in the ODEP section (high freq protection). QSC PA amps also are good but tend to be switcher supplies, which I have repaired but are pretty dangerous for a newbie with 220 VDC in the power supply. Rest of amps the AC mains section is separated from the parts that fail by a steel wall, pretty easy to stay away from. You do need a case to keep out AM/police/fire/CB/ham radio, and digital howl from computers, electric fans, coffee makers, and other appliances containing computers. Most expensive part of class AB not mentioned is the heatsink. Used heat sinks in motor drives , dead PC's etc are cheap, but take some crawling through resale shops to attaine them. Note most ali-ebay pcbs are sold without the heat sink and power supply.
If you decide on Class D you should buy a board with newest bluetooth version so that you can use high resolution codecs when streaming from your phone. What about TV? Do you need input from that? Those are mostly optical. Some of the newest only have hdmi output, but maybe converters exist.
Many ampboards runs fine on laptop power supplies that you can find for free or very little They are mostly 19 volt but Ive seen gaming laptops with higher. Again many active monitors have both analogue, digital and bluetooth input
Cheers
Many ampboards runs fine on laptop power supplies that you can find for free or very little They are mostly 19 volt but Ive seen gaming laptops with higher. Again many active monitors have both analogue, digital and bluetooth input
Cheers