I ran across the Amp Camp Amp (ACA) DIY kit designed by Nelson Pass over in the Cheap and Cheerful thread. They looked easy enough even for me to build and I wondered how they would work with the Wedgies so I decided to give them a try. These are two mono blocks that were originally designed to put out 5wpc but have been upgraded and now put out 6wpc.
This is how the kit arrives
![](http://www.audiocircle.com/image.php?id=147639)
Here are a couple of pics of the build in progress and nearing the end
![](http://www.audiocircle.com/image.php?id=147632)
![](http://www.audiocircle.com/image.php?id=147633)
I strayed from the kit a little. I used Cardas RCA jacks and binding posts instead of the ones that come with the kit. I had to enlarge the holes for the binding posts but it was very easy to do with a reamer and drill.
![](http://www.audiocircle.com/image.php?id=147634)
Once I got them finished I crossed my fingers and flipped the switches (after all, this was the first time I soldered up a PCB). No smoke
![Thumbs up :thumb:](https://www.audiocircle.com/Smileys/audiocircle/smiley_thumb.gif)
Since they worked and didn't blow up it was time to see what they sounded like. I swapped out the PrimaLuna and hooked the ACA's up.
![](http://www.audiocircle.com/image.php?id=147635)
Here's a pic of the system
![](http://www.audiocircle.com/image.php?id=147636)
So, how did they sound? Underwhelming to say the least. With the volume control all the way up the Wedgies could only manage a little over 70dB at the listening position (subs off). With the subs on I would only get a little over 80dB. Additionally the wedgies sounded thin and anemic. Some questioning on the ACA forum at DIYaudio identified the problem. It came down to differences in gain and input sensitivity (voltage needed to drive an amp to full power) between the Prologue 4 and the ACA's. The ACA's are monoblocks with 14dB of gain and an input sensitivity of 1.5V each (3V total needed to drive to full power). The Prologue 4 is a stereo amp with 29dB of gain an input sensitivity of 600mV. This created a mismatch in my system.
My DAC puts out 2V which is more than enough to drive the Prologue 4 so the Dodd Audio Tube Buffer with 0 gain is a good match. However, since the ACA's only have 14dB of gain (vs 29) and the DAC cannot put out enough voltage to fully drive the ACA's the Dodd Tube Buffer is not a good match. So I borrowed a Jolida JD-5T preamp (10dB of gain and 7V max output) from another system and used it in place of the Dodd
![](http://www.audiocircle.com/image.php?id=147637)
Now the ACA's get enough voltage and the additional 10dB of gain allow the Wedgies (sans subs) to hit over 100dB at the listening position. The ACA's no longer sound anemic. They have a full and pleasing sound. At this point they only have a couple hours on them so I will see how they do after they get some more playing time.
I cannot evaluate bass extension when using the Wedgies so later on I will move the ACA's into my office and see how they do with the LGK 1.0's in the desktop system. I may also see what they sound like with the N3's
Mike