Amp Camp Amp - ACA

I am wondering if there is an amp build that has the delicious overall sound of the ACA but with a little more low bass control?

Thanks for any suggestions.

Well, people who are experienced in designing the amp PCB's tend to maximise the width and the thickness of the traces running between V+ / V- and output transistors, as well as those running between transistor output and speaker-out eyelets. But, amplifier builders then use tiny AND quite long litz wires to extend those PCB points towards capacitor's banks and towards binding posts. This just doesn't make any sense...

You could try placing the SMPS inside the ACA, and then using solid core wires to connect it to both PCB's. Do the same with wires running from the PCB-out eyelets, to binding posts. However, this means dealing with the mains voltages, so unless you are prepared to do that, I strongly suggest to re-think the benefits vs. dangerous voltages trade-off.

Increasing the speaker' coupling cap capacitance could also help (3,300uF -> 10,000uF), but the above will make a huge difference.
 
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Well, people who are experienced in designing the amp PCB's tend to maximise the width and the thickness of the traces running between V+ / V- and output transistors, as well as those running between transistor output and speaker-out eyelets. But, amplifier builders then use tiny AND quite long litz wires to extend those PCB points towards capacitor's banks and towards binding posts. This just doesn't make any sense...

You could try placing the SMPS inside the ACA, and then using solid core wires to connect it to both PCB's. Do the same with wires running from the PCB-out eyelets, to binding posts. However, this means dealing with the mains voltages, so unless you are prepared to do that, I strongly suggest to re-think the benefits vs. dangerous voltages trade-off.

Increasing the speaker' coupling cap capacitance could also help (3,300uF -> 10,000uF), but the above will make a huge difference.

No, I don't know enough about electronics to be messing with installing the SMPS inside the ACA. But I am curious to know the theory behind why that would make a big difference.

I know enough to follow directions well, and I don't know nearly enough to try to better a well respected design. I was not really thinking about modding the ACA because I really like the sound and I don't want to risk screwing it up. I was thinking more about advice for designs where PCBs and parts are readily available.

Thanks
 
Snake oil solder Only get the good stuff

My solder was purchased from a slick talking salesman who rode into town on a shiny high polished wagon in the middle of the night . He said it was mind by virgins on an island and only melted down in poured on a full moon night quenched in high mountain artesian well waters to be annealed and finally polished with Corinthian leather . He said I would make my Amp Camp Amp project sonic qualities exceed that of the highest end McIntosh equipment it would make my Amp Camp Amp in comparison a Krill amplifier would sound like a class D Chinese made amplifier . He had papers to prove it printed on heavyweight high-gloss colored pamphlets with OSI 9000 certified tested by third-party laboratories with a frequency range extending from 1Hz past 100,000 Hz and a db rating exceeding 110db.
In all seriousness for us newbies including myself I will be throwing away my 20-year-old 60/40 Rozen for solder in my electric solder sold by BrazelOMatic from a large box store Home Depot and my free sample of leadfree solder was the most horrible stuff I’ve ever tried to use after the second resistor I gave up and tore them out and threw away that garbage never let anybody use leadfree solder . Friends don’t let friends solder lead free. Clean your boards off with alcohol you some flex on your boards or your component leads and high-quality Sauter makes life beautiful in your work and your peace of mind .
PS. Special thanks to the Mighty Zen Mod criticize constructively my soldering work in a previous post and it made me go out and research and watch the past 70 years of soldering videos from the 1940s to present day to up my soldering abilities.
 

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Eutectic solder (Sn63/Pb37) melts at a lower temperature than regular solder. I does cost more as it needs to be made with accurate proportions. Add a bit of silver (Sn62/Pb36/Ag2) and this temperature drops a bit more. Once again the price goes up. I like the low temperature melting so I get the 62/36/2.

Jim
 
Switches things on and off again
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Thanks for the clarification. Maybe you can answer a couple of other questions I have. Does running in balanced bridged mode cause the damping factor to suffer compared to running as a standard stereo amp? Also, does running in balanced bridge mode have ill effects compared to stereo mode if your speakers dip lower than the recommended 8 ohms

After consultation with those who understand this better than I do, here's a table which helps explains the pros and cons of the various monoblock operation modes, including the effect on damping factor. This table as well as wiring diagrams for each mode will soon be added to the ACA guide.
 

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I want t o build two ACA's and go for parallel mono, but since the kits are sold out I want to build my own. I have a few questions, hopefully someone will be inclined to help me out:

A few resistors (332K, 39K2 and 2K21) are very difficult to find, would it be a problem if I'd use 330K, 39K and 2K2 instead?

Would the B1 Buffered Preamp be a good preamp to combine with two of these monoblocks (unbalanced)?

Cheers,
neel
 
My personal opinion is that if ACA is not sufficient in normal single ended mode ACA is the wrong amp for the job. There are better alternatives such as M2, Aleph J, MoFo, F5 etc.


For me the ACA works very well with my upgrades such as linear PSU, caps. It would probably work well also just "as is".