With so many kits out there, from expensive audiophile kits to cheap chinese eBay kits, I'm seeking suggestions/recommendations on a kit that would meet the following requirements:
-50W (a bit more is ok) into 8 ohms, but also 4 ohm stable
-class AB discrete
-no heat sink included in the kit (not needed, I've got piles of heat sinks already)
-power supply also not necessary, just the amplifier (I can easily put a power supply together)
-must sound respectable at all volume levels (full rated power at <1% THD)
-reasonably robust (should be expected to survive an accidental short/overload)
-relatively inexpensive (<$50 per channel)
Does not have to be pre-assembled, I'm fine and fairly quick with soldering. In fact it doesn't even have to come with the components, just a bare board with parts list and schematics is fine (I have to make a Digikey order soon anyways). I just don't have the time to design an amplifier completely from scratch (many other projects on the go) or the resources necessary to make my own PCBs, and honestly, why re-invent the wheel?
Thanks in advance for your input!
-50W (a bit more is ok) into 8 ohms, but also 4 ohm stable
-class AB discrete
-no heat sink included in the kit (not needed, I've got piles of heat sinks already)
-power supply also not necessary, just the amplifier (I can easily put a power supply together)
-must sound respectable at all volume levels (full rated power at <1% THD)
-reasonably robust (should be expected to survive an accidental short/overload)
-relatively inexpensive (<$50 per channel)
Does not have to be pre-assembled, I'm fine and fairly quick with soldering. In fact it doesn't even have to come with the components, just a bare board with parts list and schematics is fine (I have to make a Digikey order soon anyways). I just don't have the time to design an amplifier completely from scratch (many other projects on the go) or the resources necessary to make my own PCBs, and honestly, why re-invent the wheel?
Thanks in advance for your input!
My advice is to skip the cheap Chinese Ebay kits and get something from a reputable source. The low price is attractive until you realise you sold a pup with incomplete/nonexistent documentation and counterfeit parts, that is almost guaranteed to be a source of frustration. Of all the mistakes I've made in my life that isn't one of them - so I don't speak from experience and you can take my comments with a grain of salt.
With that budget perhaps look to a chipamp/gainclone?
Sorry I didn't read your message properly. Rod Elliott sells bare boards; I've built several of his projects and have been very satisfied with the results. I recommend his P3A project.
http://sound.westhost.com/
With that budget perhaps look to a chipamp/gainclone?
Sorry I didn't read your message properly. Rod Elliott sells bare boards; I've built several of his projects and have been very satisfied with the results. I recommend his P3A project.
http://sound.westhost.com/
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This cheap Chinese clone is popular:
http://www.diyaudio.com/forums/solid-state/112453-nap-140-clone-amp-kit-ebay.html
Douglas Self's Blameless amplifiers:
The Signal Transfer Company
Or, look for used/broken power amp at a pawn shop and repair/upgrade it.
http://www.diyaudio.com/forums/solid-state/112453-nap-140-clone-amp-kit-ebay.html
Douglas Self's Blameless amplifiers:
The Signal Transfer Company
Or, look for used/broken power amp at a pawn shop and repair/upgrade it.
I've been reading stuff off this guy's website for years and never realized he actually sold stuff!
There's a couple interesting amp board there. Prices seem reasonable (not much more than it would cost me to have my own PCBs professionally manufactured). As for the components I already have most of the resistors, capacitors, diodes in stock leaving mostly the transistors which I can get for next to nothing on DigiKey.
Also interesting.
Thanks for the suggestions!
I bought the "MX50" cheap Chinese amp. I paid almost nothing planning on using it just for education. The kit did not match the schematic and parts are, well cheap does not describe it. Putting the as-delivered into Spice, it has serious flaws. It might be useful for testing protection to the failure limit.
So many kits are just the amp. Not an amplifier system. Insufficient input network, output network, protection, mute etc. Rather than mod yet another e-bay used wonder, I decided only designing my own would teach me what I want to learn better than reverse engineering something that turns out, was not well engineered. It has taught me many of the forum posts have wonderful and occasionally clever ideas, but they are not the driving force in the design not fixing the real problem, and a great many production units are very poorly designed. SOP rather than engineer so miss-matches carry on and on. For someone like me who is very new ad the finer details of amp design, consider this a very harsh condemnation.
Just build a GainClone. I am informed they are really quite good if done well mechanically. No kit needed. Flying point to point works fine.
So many kits are just the amp. Not an amplifier system. Insufficient input network, output network, protection, mute etc. Rather than mod yet another e-bay used wonder, I decided only designing my own would teach me what I want to learn better than reverse engineering something that turns out, was not well engineered. It has taught me many of the forum posts have wonderful and occasionally clever ideas, but they are not the driving force in the design not fixing the real problem, and a great many production units are very poorly designed. SOP rather than engineer so miss-matches carry on and on. For someone like me who is very new ad the finer details of amp design, consider this a very harsh condemnation.
Just build a GainClone. I am informed they are really quite good if done well mechanically. No kit needed. Flying point to point works fine.
Also a vote for ESP. Note you will need several boards to make up an amplifier "system". Amp, p/s, protection etc. Read all his tech papers first. Actually, read all of them anyway.
I've said elsewhere, that a lot of schematics of L series kits have deliberately false or obscured schematics when published at sellers' Ebay sites. This was certainly true of L12 which looked like nonsense but simmed fine when the real schematic was posted.
'dunno how this works, because some kits arrive with the proper schematic, others are emailed with your invoice and more recently, some sellers give no documentation other than sketchy sales info. This may be OK for clever guys with experience in building amps but really spoils it for average DIYs who won't know what they've got or how to adapt it unless someone reverse engineers it; something that could be done by copycats anyway but may be difficult for the guy who is entitled to know, having bought a part-product he may have to assemble and join to other devices some uncertain way, just to see if it works.
That aside, Ebay kits based on cloned designs are still amazing value and do provide low cost products for a wider range of people than those who can afford more finessed, fully supported kits at several times the price.
Fakes and lousy designs are another matter, but I stick with stores who have proven to be reliable, where I haven't yet been stung with bad parts over some years. That's not to say I don't blame them when circuits don't work - that's a human trait 😉
'dunno how this works, because some kits arrive with the proper schematic, others are emailed with your invoice and more recently, some sellers give no documentation other than sketchy sales info. This may be OK for clever guys with experience in building amps but really spoils it for average DIYs who won't know what they've got or how to adapt it unless someone reverse engineers it; something that could be done by copycats anyway but may be difficult for the guy who is entitled to know, having bought a part-product he may have to assemble and join to other devices some uncertain way, just to see if it works.
That aside, Ebay kits based on cloned designs are still amazing value and do provide low cost products for a wider range of people than those who can afford more finessed, fully supported kits at several times the price.
Fakes and lousy designs are another matter, but I stick with stores who have proven to be reliable, where I haven't yet been stung with bad parts over some years. That's not to say I don't blame them when circuits don't work - that's a human trait 😉
Take a look here:
Akitika Store
The GT-101 is a complete kit...but the separate amp, power supply modules, and transformers are available for separate sale. Rock solid implementations and a great assembly manual.
Akitika Store
The GT-101 is a complete kit...but the separate amp, power supply modules, and transformers are available for separate sale. Rock solid implementations and a great assembly manual.
On the contrary my experience had been very favorably, I bought kits(in excess of 6) from Chinese Ebay sellers from HK or China, all my sets were complete, with schematics if you request one. Having said that you must have some experience with building amps.They are not for novice. They DO NOT provide step by step documentation, I don't need them anyway. Whether the parts are genuine I cannot fully say with full confidence, however they do work. In the end they do sound very good indeed.
I am not sure whether you have bought any kits from Ebay yourself, if not I suggest you refrain from commenting.
If you had read my comment properly you would see that I stated up-front that I've not bought one of the Ebay kits. My observations are based on comments of others here on DIYAUDIO who have.
Why should I refrain from offering my opinion on a public forum, particularly when I offered the an alternative that meets his criteria? I've given my opinion, you've given yours, and others have given theirs. Hopefully TheMG is in a position to make a better informed decision. Why are you afraid of people expressing an opinion that differ to your own?
Just to point out... this is definitely not the first time I've put together a kit (from components), nor is it the first time I've put together an amplifier.
Right now it's simply a question of time and money. I can't be spending $100+ per channel as I need 5 channels in this amplifier (it adds up very quickly!). I could build an amplifier from schematics without too much difficulty, but with work, life, and other projects, I don't have the time to go through the PCB design phases and such.
Anyways... I might consider a gainclone kit provided that the IC it is based on will remain available for the foreseeable future. I don't want to build an amp using a chip that will be EOL in the next couple of years.
The advantage of discrete design, is that no matter how old, there is always the possibility of substituting equivalent (or better!) parts if the original ones are no longer manufactured.
This amplifier will be used in my home theater system along with a Emotiva UMC-200 receiver. Right now I've got a mix of random 2-ch amplifiers (including a car audio amp, yikes!). I'm not satisfied with the setup, and it sure ain't pretty! It was temporary anyways. So I'm looking to consolidate everything into ONE amplifier so I can eliminate this disastrous rat's nest.
Right now it's simply a question of time and money. I can't be spending $100+ per channel as I need 5 channels in this amplifier (it adds up very quickly!). I could build an amplifier from schematics without too much difficulty, but with work, life, and other projects, I don't have the time to go through the PCB design phases and such.
Anyways... I might consider a gainclone kit provided that the IC it is based on will remain available for the foreseeable future. I don't want to build an amp using a chip that will be EOL in the next couple of years.
The advantage of discrete design, is that no matter how old, there is always the possibility of substituting equivalent (or better!) parts if the original ones are no longer manufactured.
This amplifier will be used in my home theater system along with a Emotiva UMC-200 receiver. Right now I've got a mix of random 2-ch amplifiers (including a car audio amp, yikes!). I'm not satisfied with the setup, and it sure ain't pretty! It was temporary anyways. So I'm looking to consolidate everything into ONE amplifier so I can eliminate this disastrous rat's nest.
You know... the more I think about this the more I'm starting to realize I should just buy the matching Emotiva UPA-500 amplifier.
$400 - 5 channels, 80W into 8 ohms, 120W into 4 ohms. Discrete AB design. Exactly the kind of thing I'm looking for.
It's starting to look like it's going to be pretty difficult to beat this price/performance with a DIY amp unless done completely from scratch (which I don't have the time for).
Thoughts?
$400 - 5 channels, 80W into 8 ohms, 120W into 4 ohms. Discrete AB design. Exactly the kind of thing I'm looking for.
It's starting to look like it's going to be pretty difficult to beat this price/performance with a DIY amp unless done completely from scratch (which I don't have the time for).
Thoughts?
It makes sense to use commercial products for HT amplifiers and receivers. The cost and complexity of a DIY build makes them a chore with not great chances of also having the convenient features, reliable protection systems and flexibility of commercial products,
Stereo amplifiers though, are based on very simple technology with only the frills of remote control source switching and volume control which aren't critical to use anyway. To me, it makes sense to keep the DIY effort to these traditional music-only or music-video applications intended for stereo in domestic systems.
Then its only a question of whether you want to remain a DIY kind of guy or you're happy to settle back with commercial retail products, whether multi-channel HT or simply stereo. There are plenty of great, affordable HT amplifiers out there for dirt cheap (not sure if I would go with Emotiva, based on opinions expressed here and from a friend who owned some stereo models) and even more options in used, reputable equipment
DIY at least opens up the possibilities, whatever the bean-counting figures add up to. It would be crazy not to build stereo equipment or at least upgrade existing black boxes with inexpensive power amp and protection circuits to suit. Experimenting maintains interest, audio experience and a desire to keep learning, too. 'Can't see that as a bad thing.
Stereo amplifiers though, are based on very simple technology with only the frills of remote control source switching and volume control which aren't critical to use anyway. To me, it makes sense to keep the DIY effort to these traditional music-only or music-video applications intended for stereo in domestic systems.
Then its only a question of whether you want to remain a DIY kind of guy or you're happy to settle back with commercial retail products, whether multi-channel HT or simply stereo. There are plenty of great, affordable HT amplifiers out there for dirt cheap (not sure if I would go with Emotiva, based on opinions expressed here and from a friend who owned some stereo models) and even more options in used, reputable equipment
DIY at least opens up the possibilities, whatever the bean-counting figures add up to. It would be crazy not to build stereo equipment or at least upgrade existing black boxes with inexpensive power amp and protection circuits to suit. Experimenting maintains interest, audio experience and a desire to keep learning, too. 'Can't see that as a bad thing.
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Is that with regard to their amplifiers or their receivers, or both? What is bad about it?
My main reason for purchasing the Emotiva UMC-200 was that it is the only HT receiver with line-level outputs I could find at a price that isn't absolutely insane.
I want to use my DIY Hypex UcD400 stereo amplifier for the main left/right channels, and use the 5-channel amp for the surrounds and the center channel.
Having a HT receiver with line-level outputs allows me to do just that.
Sure, I could have purchased an all in one 7.1 HT receiver and hacked it to bring out the main left/right outputs as a line-level output tapped off prior to the internal amplifier, but I decided against it.
I was going to suggest that. You can't beat their try and return policy. Some love them, some don't so much. I think the price makes people think they can't be good. I don't know. Good design is not necessary expensive. You could also consider Outlaw. Well respected for their amps and the same by/try policy. I tried the AV preamp from both and returned both as the HDMI switching was just plain not solid. Wound up with a NAD AVR in my movie room.
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