Low power 2 W @ 8 ohm, 4 - 16 ohm usable simple, class A SE - any recommendations?

Another one to consider is Yamaha YDA138.
I bought one of these a few years ago and it sounds quite good.
https://www.ebay.ca/itm/125149452136
1664301513685.png
 
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Hi @Koifarm,
I have made my own PCB’s(through hole)For 4, 8 or 16 lme49600 parallel. I can share gerber files and schematic so you can order your own PCB’s. The 4 lme49600 is for 8ohm and 8watt. Power supply is two batteries or lt3045/3094 supply.
Thank you for your generous offer. I would like the 4 parallel version, you can use p.m. if you do not want to publish them. They will be for my personal, non-commercial use.

Kindest regards,

M
 
1 transistor, 1 trimmer, 1 power resistor. 1 input cap. 1 output cap. Nothing else.
The quality of the parts will make the sound - a lot to proof;-)
No interactive or active load.
No balancing.
Your last amp;-)
The first amp I ever made was exactly this! It sounded great but it ran very hot being single ended class A. I used MJ15003 transistors and big Dale 50 watt emitter resistors and massive bipolar cap on the output. Huge heat sink is a must as is a large stiff power supply. It’s as basic as it can get! The sound of one transistor clapping!
 
Hi @Koifarm,

Thank you for your generous offer. I would like the 4 parallel version, you can use p.m. if you do not want to publish them. They will be for my personal, non-commercial use.

Kindest regards,

M

Below schematic and PCB design for the 8 Watt amp.
If you want to use battery just leave the power supply out.
Below also Gerber files for PCB, only 6 euro incl. shipping now for 5 PCB's at JLCPCB.
Size PCB is 100 x 85 mm.
You can use heatsink at bottom of PCB.
For critical noise purpose you can use LT3045/3094 boards instead of LM317/337.
Use transformer 2 x 12V 1A. (25VA) or two batteries 12…15V.

8 Watt LME49600 amp.jpg


LME49600 PCB.jpg


LME49600-4 Schematic.jpg
 

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The first amp I ever made was exactly this! It sounded great but it ran very hot being single ended class A. I used MJ15003 transistors and big Dale 50 watt emitter resistors and massive bipolar cap on the output. Huge heat sink is a must as is a large stiff power supply. It’s as basic as it can get! The sound of one transistor clapping!
;-)
At moment I do listen at 10 V, 1 A. At 85 dB fullrange. Party level;-) And: Nothing does "clap"-)
But I did hear hundreds (not dozens) of transes, diodes, caps, resistors, wires... to get the best parts. My experience: only every tenth part is suitable for audio. The other nine do use for lifts, mowers, traffic lights and so on;-)
 
Why a alternate? LME49710 is very low noise and has Dip format. This is needed when driving >110db sensitive tweeters.

Possible replacements are NE5534, AD825, LT1363, OPA211, AD847 or on adapters opa1611 etc.
 
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The drivers are 16 ohm. And they can be used directly with headphone output of a tablet or a PC. I will do some more trials and measurements. The good thing is there is really zero noise. I do not know how the board is wired, maybe it could be modded. Maybe it is time to try a single transistor amp instead🙂