What would be a good amp for a first timer.

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Hi, I am thinking about building a Class D amp based off a existing design but don't know where to start.
Low heat and clean output are my number 1 goals, power is secondary.

Leaning towards ljm_ljm's power amps but I also want to have a preamp in the same box.

Which of his designs would put out the least amount of heat?
Which preamp would be a good fit?
Which power supply?
Can I use the same power supply board to run the pre?
With the AC to DC power supply do I just have to have a transformer in between the board and the mains socket to step down the voltage for it or do I need more?
Should I run the power amp at the lower or higher end of it's voltage range?

It will be powering a pair of Zaph Audio ZRTs

Also, If anyone has an other amp in mind do speak up.
 
Have a look at Arjen Helder's stuff on eBay. You can get his TA2020 MKIII board and a tube buffer to run with it both off the same 12v power supply.

wonderco_buy do really nice little chasis (also eBay)

Nice easy first project that sounds incredible.
 
Not really an easy question to answer; we don't know anything about your skill level, or budget. Those two are fairly critical.

You need a good set of basic tools. Purchased new, although what comprises the set will vary depending on who you ask, in my mind you need about $200 worth.

However that assumes you're actually "building" something. Maybe all you need are a few screwdrivers, to assemble a kit like Arjen Helder's, which are pretty basic.

Can you build an enclosure, do you need a premade one, can you drill a hole in aluminum? These things will affect what first project you undertake.

Do you have soldering skills? If not, get some used electronics ... doesn't really matter what they are ... and take them apart. Practice desoldering components, and re-soldering them.

Are you electrically safe? Do you have a dedicated workspace that can be secured from others? Read up on best safety practices when dealing with household and DC current.

Maybe you're more of a handyman and less an electronics guru. Perhaps a speaker project would be better for you to start.

If some of this post is a bit pedantic, I mentioned earlier that we don't know anything about your experience or skills, and this is "the interwebs"; if you're mature enough that this is talking down to you, maybe someone searching and finding this thread isn't. So, please forgive me.

My basic electronics tool kit would consist of:
--A temperature controlled soldering station. Hakko 936 or equivalent (they have a new model that replaces the 936, is a bit better, and costs the same, but I forget the model #). About $100. You can get Chinese knockoffs, but in my opinion you won't regret splurging the $20 or $40 extra on the Hakko once you use it a few times. Others may disagree, but that's how I feel about it.

--JIS screw drivers; you can get away with a $10 set from a computer store; they are usually called micro drivers. Note that JIS drivers work with Phillips screws but not vice-versa, and most electronics use the JIS screws.

--Some kind of sharp knife. Hopefully you can use one without excess bloodletting. A few dollars. Hot tip: NEVER cut anything in the vicinity of your leg. If you cut the femoral artery, you will be dead in five minutes. I'm adding this because I actually know someone who died from this, he was poked by a deer horn in the thigh loading it into his truck bed.

--A set of electronics pliers and cutters; you absolutely need needle nose and side cutters.

--Some screw and bolt tools.

--A stepped drill bit; access to a drill. Assuming you have a drill and don't need to buy one, say $10.

--Some kind of vice suitable for electronics. Chinese knockoffs of the PanaVice are maybe $10.

--A non-conductive surface. A wooden cutting board, perhaps.

--Anti-static wriststrap; cheap at computer stores.

--Something to hold small parts. You can get away with egg crates.

--A decent lamp to work with, a magnifying glass is useful. Scrounge them or buy them.

--A Volt-Ohm-Meter. Buy what you can afford; could be as low as $10. Since you will use multiple meters if you have them around, don't worry too much if it's "good enough". You can buy another later, and you'll still find use for the first one. Many people have three or five and use them all simultaneously.

--A Soldapullit or equivalent. Some desoldering wick. Some solder ... lead free is the current standard but if you can find lead-tin solder it's easier to work with. Maybe $35 for the three. Note: If you can't afford a soldering station like the Hakko and use a pencil iron, then you should seriously consider sourcing the lead solder somehow; it's much easier to work with.

I'm sure I overlooked something others feel is either handy or essential, and I'm also sure there are those (myself included) who started with less, but we all ended up buying the stuff on this list eventually, plus some. If you decide to start with speakers, then the usual woodworking tools, a pencil iron, the pliers and something to drill holes and turn screws or bolts, and some solder is all you need. The VOM would be handy as well. Lots of beginner-level plans everywhere, including this site.

Oh, and have fun. It's a great hobby.
 
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Hmmm ... I see you have the Zaph Audio speakers. Nevermind the building speakers part; sorry.

I would look at the Arjen Helder boards as a beginner kit, you would learn a bit from it and they sound good enough for the cost. There is room to play with them to adjust the sound quality, which will involve soldering skills.

If you want to take on something more challenging, then maybe try a gainclone or some other design found in the "Chip Amps" section (Home/Forums/Amplifiers ...).

I don't see any reason why you couldn't "jump right in" with a scratch-build kit, maybe with a group buy PCB as a start, or a tube amp, since thousands have done so before, but any mistakes will be proportionally more expensive, and higher voltages mean more safety needs to be looked at. Up to you.
 
I have my doubts about gain clones. They are cheap meadeochre amps IMHO.

If you only have pennies to spend then they are OK.

I built a top-end LM3886 gain clone and the results were TBPO "dissapointing".

The Pass projects are vastly superior but do require a bit more effort to get them right.
 
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Not really an easy question to answer; we don't know anything about your skill level, or budget. Those two are fairly critical.

You need a good set of basic tools. Purchased new, although what comprises the set will vary depending on who you ask, in my mind you need about $200 worth.

However that assumes you're actually "building" something. Maybe all you need are a few screwdrivers, to assemble a kit like Arjen Helder's, which are pretty basic.

Can you build an enclosure, do you need a premade one, can you drill a hole in aluminum? These things will affect what first project you undertake.

Do you have soldering skills? If not, get some used electronics ... doesn't really matter what they are ... and take them apart. Practice desoldering components, and re-soldering them.

Are you electrically safe? Do you have a dedicated workspace that can be secured from others? Read up on best safety practices when dealing with household and DC current.

Maybe you're more of a handyman and less an electronics guru. Perhaps a speaker project would be better for you to start.

If some of this post is a bit pedantic, I mentioned earlier that we don't know anything about your experience or skills, and this is "the interwebs"; if you're mature enough that this is talking down to you, maybe someone searching and finding this thread isn't. So, please forgive me.

My basic electronics tool kit would consist of:
--A temperature controlled soldering station. Hakko 936 or equivalent (they have a new model that replaces the 936, is a bit better, and costs the same, but I forget the model #). About $100. You can get Chinese knockoffs, but in my opinion you won't regret splurging the $20 or $40 extra on the Hakko once you use it a few times. Others may disagree, but that's how I feel about it.

--JIS screw drivers; you can get away with a $10 set from a computer store; they are usually called micro drivers. Note that JIS drivers work with Phillips screws but not vice-versa, and most electronics use the JIS screws.

--Some kind of sharp knife. Hopefully you can use one without excess bloodletting. A few dollars. Hot tip: NEVER cut anything in the vicinity of your leg. If you cut the femoral artery, you will be dead in five minutes. I'm adding this because I actually know someone who died from this, he was poked by a deer horn in the thigh loading it into his truck bed.

--A set of electronics pliers and cutters; you absolutely need needle nose and side cutters.

--Some screw and bolt tools.

--A stepped drill bit; access to a drill. Assuming you have a drill and don't need to buy one, say $10.

--Some kind of vice suitable for electronics. Chinese knockoffs of the PanaVice are maybe $10.

--A non-conductive surface. A wooden cutting board, perhaps.

--Anti-static wriststrap; cheap at computer stores.

--Something to hold small parts. You can get away with egg crates.

--A decent lamp to work with, a magnifying glass is useful. Scrounge them or buy them.

--A Volt-Ohm-Meter. Buy what you can afford; could be as low as $10. Since you will use multiple meters if you have them around, don't worry too much if it's "good enough". You can buy another later, and you'll still find use for the first one. Many people have three or five and use them all simultaneously.

--A Soldapullit or equivalent. Some desoldering wick. Some solder ... lead free is the current standard but if you can find lead-tin solder it's easier to work with. Maybe $35 for the three. Note: If you can't afford a soldering station like the Hakko and use a pencil iron, then you should seriously consider sourcing the lead solder somehow; it's much easier to work with.

I'm sure I overlooked something others feel is either handy or essential, and I'm also sure there are those (myself included) who started with less, but we all ended up buying the stuff on this list eventually, plus some. If you decide to start with speakers, then the usual woodworking tools, a pencil iron, the pliers and something to drill holes and turn screws or bolts, and some solder is all you need. The VOM would be handy as well. Lots of beginner-level plans everywhere, including this site.

Oh, and have fun. It's a great hobby.

Can a router cut holes in aluminum? If so, yes I can cut holes.

I have soldered once, did not turn out the best but it was a bit of an odd shape to solder to.

Getting people not to touch something I am working on will not be a problem.

I do have a pocket knife,

Got a fair amount of tools in general.

I have a drill and I can get the bit just down the road.

I have no conductive tables.

Don't need the Anti-static wriststrap, far too much humidity in the air to need it.

what about Hypex modules ? not cheap but superb quality , powerful , and easy to assamble

I have looked at them but they are kind of pricey.

Class D can have its problems with the choice of load. If you get it right, the results can be very good, if you get it wrong the results will be disappointing.

As a first timer, you might prefer the more reliable Class AB approach.

The whole point of me building a class D is to replace my Onkyo 605 which is a class AB that puts out a huge amount of heat and because it is being funded by it's sale I have to keep costs down.

I should add that I need at least 30W per a channel, the max that can be sent to the ZRT before it runs out of x-max (when running fullrange).


I have been turn off class T due to some less than good measurements of Sure amps I have seen on this board and because no one seems to have checked how other T amps perform.
 
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From what I can tell the LJM amps are hard to beat bang/buck, and there's a thread where they showed superb measurements.

The only thing I would wonder about is parts quality/reliability given the dirt cheap prices.

connexelectronics also makes some IRS2092 amps that are about double the price which I would trust more, though have no facts to support that.
 
Hmm. Interesting questions. You need an inexpensive control preamp and a power amp board. I can recommend the Sure TK2050 2 channel board and the matching Meanwell power supply via Parts Express. This is about $100 total. Given your apparent mechanical skill, you should be able to mount the board OK in a ($8) plastic box from Radio Shack. The preamp is a bit more difficult. The Gemini PA7000 or the similar Pyramid preamp are available from Amazon. These cost around $100, the Gemini a little more, the Pyramid a little less. I myself have the Gemini, and it is very good. Now, if you want to try something more DIY, there is a preamp kit from Kits 'r Us sold as the K100 from Carl's Kits and various other suppliers. This is easy to build (get a cheap 30W soldering iron and good thin rosin core solder for this) and can also be planted in a Radio Shack black box. This kit costs around $25 and works very well. If you need an input selector switch, these are available from various suppliers (you can use an A-V switch for this, just ignore the video connectors).

This will get you very good to excellent results, with equipment that runs typically at room temperature even when working hard. Best of luck with your project.
 
Strictly speaking, a preamp is not needed, but is very useful under real world listening conditions. Many folks now keep their music collections as MP3 (or other format) files on a computer, and can control not just volume but tone on the computer. However, the sound chipsets on computers are very variable in terms of output level. Also, many people now run >1 computer, so source selection becomes an issue. MP3 portable players also have wide variation in output level. I find that the $100 or so for a preamp pays for itself in convenience and avoided aggravation very quickly. However, if money is tight, a $5 50Kohm stereo potentiometer mounted in a $2 plastic box, spliced into a used stereo patch cable works just fine.

And yes, plenty of power amps have level conntrols, but they all (with the exception of a few competing Chinese products, not readily available here) cost a lot more than a Sure board.
 
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