Well, it looks something like this..
That kind of PSU won't fit in the usual ACA chassis, but it will fit in the Mini 3U chassis. I used a set of boards laid out by another DIY member and stuffed them into an old Hafler chassis. These included their own CRC filter, and I added a big C and R in front.
The site you're looking for is ACA amp with premium parts
That kind of PSU won't fit in the usual ACA chassis, but it will fit in the Mini 3U chassis. I used a set of boards laid out by another DIY member and stuffed them into an old Hafler chassis. These included their own CRC filter, and I added a big C and R in front.
The site you're looking for is ACA amp with premium parts
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Try heating up the solder in the hole and, while it’s still hot, blowing hard on it. This works surprisingly well, and I do it when a wick isn’t at hand. Wear a pair of safety glasses because it does splatter a bit sometimes when you blow hard. I know, it’s a little crazy, but it works for me.
This is going to be an odd question but this is all I have to test with right now.
I just finished a 1.8. Everything seems fine but all I have to test sound with is an iPhone, lightning to rca cable and an old 4ohm driver stolen from a sound bar sub. My question is how loud should it sound? I can easily hear music from either side but it’s about the level of a normal conversation.
I just finished a 1.8. Everything seems fine but all I have to test sound with is an iPhone, lightning to rca cable and an old 4ohm driver stolen from a sound bar sub. My question is how loud should it sound? I can easily hear music from either side but it’s about the level of a normal conversation.
I would try it on a regular speaker and see what happens. Free hanging speakers do weird things?
I use my iphone with a Marantz integrated amp. I have to turn the volume knob up 2 to 3 times more than I would if I was using my CD player. Having said that, when I hook it up directly into a 70 watt amp it does play as loud as i need it too.
Try a different source if possible. Also try different sites to stream from on your iphone.
Also go through the instructions step by step and recheck your work.
I use my iphone with a Marantz integrated amp. I have to turn the volume knob up 2 to 3 times more than I would if I was using my CD player. Having said that, when I hook it up directly into a 70 watt amp it does play as loud as i need it too.
Try a different source if possible. Also try different sites to stream from on your iphone.
Also go through the instructions step by step and recheck your work.
I'd expect it to be a bit louder than that with the volume on the iPhone all the way up. However, I'm not sure of the voltage output with the newer phones.
Either way, if you have music with nothing sonically causing you concerns (music from both channels, no pops or scratchy noises etc), I'd suggest putting a pre-amp into the chain. I'd do that before testing with your more expensive speakers just out of an over-abundance of caution.
Either way, if you have music with nothing sonically causing you concerns (music from both channels, no pops or scratchy noises etc), I'd suggest putting a pre-amp into the chain. I'd do that before testing with your more expensive speakers just out of an over-abundance of caution.
Mulburg,
Chances are your iPhone has a limited output by design.
Have a look at post #5957. It shows you how to check the output of your phone and the amplification of the ACA.
Quote: ''Here is a way to test your ACA is amplifying correctly. I just tried it on mine and this is what I did.
Used my mobile phone and went to this site for the 1 kilo Hertz test tone, it is a bit louder than some. 1 KHz Sine Test Tone - YouTube
I turned my phone's volume to maximum and measured the AC voltage at the head phone socket playing the tone. Mine is 0.43 volts AC. Yours might be more or less, just note what it is.
Then I plugged the phone into my ACA and measured the output at the speaker terminals. (No speakers connected.) I get 1.622 volts AC.
If I connect my speaker (8 ohms) and measure I get 1.57 volts AC.
Again yours might be different just note it.
So on my amplifier for an input of 0.43v ac I get 1.57v ac out.
3.6 times amplification and you should get something similar if all is well.
Hope that helps.''
If that is the case you will need a pre-amplifier to increase your volume.
Alan
Chances are your iPhone has a limited output by design.
Have a look at post #5957. It shows you how to check the output of your phone and the amplification of the ACA.
Quote: ''Here is a way to test your ACA is amplifying correctly. I just tried it on mine and this is what I did.
Used my mobile phone and went to this site for the 1 kilo Hertz test tone, it is a bit louder than some. 1 KHz Sine Test Tone - YouTube
I turned my phone's volume to maximum and measured the AC voltage at the head phone socket playing the tone. Mine is 0.43 volts AC. Yours might be more or less, just note what it is.
Then I plugged the phone into my ACA and measured the output at the speaker terminals. (No speakers connected.) I get 1.622 volts AC.
If I connect my speaker (8 ohms) and measure I get 1.57 volts AC.
Again yours might be different just note it.
So on my amplifier for an input of 0.43v ac I get 1.57v ac out.
3.6 times amplification and you should get something similar if all is well.
Hope that helps.''
If that is the case you will need a pre-amplifier to increase your volume.
Alan
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I have both an iphone 7 and 11. The 7 is "louder" when hooked up to the same amp. But not by much. I think you will need a preamp with the iphone.
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Impedance graph SR71
The graph is pretty flat. I tried attaching the graph so let's see if it works?
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The lead spacing on the C3 and C4 capacitors provided are narrower than the holes on the board and the caps won’t full insert. Is it ok to leave these caps hovering over the board on longer leads or is there a trick to make them full insert and sit directly on the board like the other caps do?
Just completed my first ACA 18 ! Great sounding amp. small but sweet, clear and clean sound. Beat the sh.t of my Yamaha 150watt AVR !Looking forward to building my 2nd ACA. Thank you very much. Great product !
in a blind test, mistaken for a 300b set...
Does not matter. Just solder them in at the centre of their travel is fine.
Push them in gently and solder them in with a small space above the board, don't stress the leads by pushing them down to the board.
