Amp Camp Amp - ACA

[Alan4411]

Ok these Red LEDs aren't cutting it, I killed one of my Blue LEDs, does anyone know the Specs on these? I'm sure I can get them from Mouser or DigiKey.

Mark

Zen Mod is right - the cheapest, only one factor is important - Does it fit the hole?
Then order a packet of 2 or 5 because the one you have will likely be a different colour or brightness to the new one.

If you build from the kit then the limiting resistor is already there it is R13 10k ohms.
Just remember the short lead (or flat on the body) goes to the Negative connection. Step 38 on the build guide.
Alan

 

[6L6]

Hi, Do you have to flip the switch up or down to bridge to xlr mono? Thanks.

Neither. If you use the XLR input it will be a bridged monoblock, and you take the output from the black speaker posts,

 

[Mark Johnson]

Clever Jimmy uses a 9V battery and a 1K series resistor to test his LEDs. He learns (a) whether the LED is alive or dead; (b) which of the two leads goes to "+" and which goes to "-"; (c) what is this LED's color and relative brightness. Clever.

 

[6L6]

The important trick with an LED is to use the resistor in series with (either) of the legs, it keeps current down and will save the LED from burning out when the voltage gets too high.

(I.E., what Mark said... )

 

[motospark]

Hi all, thanks for all the helpful information that you provided for my replacement LED. Yeah running the LED off a 9V battery was kind of silly and proved to be down right destructive LOL. What I ended up using was a coin type battery from an instant thermometer CR1226 3V. I wish DIY would have separated these in the kit since they are both clear, but hey if your a DIY you should be able to figure this out . I'm learning. YouTube is a terrible thing to waste. I may just go the easy route and ask DIY to send me replacements.


I love this little Amp, I have it now running off my Parasound Halo Integrated and I'm amazed that it can drive my Vandersteen 2cis. Bass is punchy and Mids and Highs are Crystal Clear. What a great Kit. I may purchase another and run as Mono blocks though this Single Amp gets loud enough to run in my apartment.

Mark

 

[adason]

...or build something like F5, M2, Aleph J.

 

[motospark]

Hummm.

...or build something like F5, M2, Aleph J.

I'll have to check them out, thanks .

Mark

 

[aljordan]

Hi,

I just built the 1.6 version with the 24 volt power supplies. I've read in one post that the correct bias for the 24 volt supply is 12 volts, and 11.8 volts in another post. Does anyone know which is the correct value? Does it not really matter a whole lot?

Thanks!

 

[kstagger]

Hi,

I just built the 1.6 version with the 24 volt power supplies. I've read in one post that the correct bias for the 24 volt supply is 12 volts, and 11.8 volts in another post. Does anyone know which is the correct value? Does it not really matter a whole lot?

Thanks!

12V is correct. But it takes a lot of patience to get there; turn the pot too much and you easily overshoot the value you are aiming for. I'm impatient that ~11.8V was "close enough" since I really wanted to hear the amps. I'll rebias before I finish the rest of the chassis assembly.

 

[Zen Mod]

be a Sissy , like Mighty ZM - use multiturns everywhere

 

[motospark]

Good Enough

12V is correct. But it takes a lot of patience to get there; turn the pot too much and you easily overshoot the value you are aiming for. I'm impatient that ~11.8V was "close enough" since I really wanted to hear the amps. I'll rebias before I finish the rest of the chassis assembly.

I couldn't hit 12 on the dot, I also settled for 11.8v.

 

[aljordan]

12V is correct. But it takes a lot of patience to get there; turn the pot too much and you easily overshoot the value you are aiming for. I'm impatient that ~11.8V was "close enough" since I really wanted to hear the amps. I'll rebias before I finish the rest of the chassis assembly.

Thanks. I could get all of them to 11.97 or 11.98. They are so sensitive that I have to meditate for 10 minutes before trying to move the screwdriver.

 

[MEPER]

The trick is to adjust in small steps as there is a delay until the change is "settled". I did not find this part difficult. I think the long term stability is the same as the multiturn pots.

 

[Zen Mod]

Pa always sez - do it in halfway steps

 

[cRomer]

Hi Everyone,

Just finished both my ACA 1.6 monos. When I powered them up one has both LEDs in blue and the other one has both LEDs in red. Please help what is wrong. Do I have the wrong LEDs with the red one? Blue seems normal to be normal for amps.


Thanks in advance.

 

[halitun]

Hi cRomer. - They supply four LEDs, two red and two blue. I was puzzled why I had two extra LEDs. By luck I installed the two blue ones and then read here on the forums that they supply both red and blue LEDs.

 

[motospark]

Both Blue and Read

Hi Everyone,

Just finished both my ACA 1.6 monos. When I powered them up one has both LEDs in blue and the other one has both LEDs in red. Please help what is wrong. Do I have the wrong LEDs with the red one? Blue seems normal to be normal for amps.


Thanks in advance.

The Kit Comes with both Blue and Red, 4 in total, ya just have to figure out which one is which. I used a 3v coin battery.

 

[mpitogo]

By luck I installed the two blue

Lucky you! I tested for color when I saw 4 extras for a mono pair. Thankfully this build was very well detailed in the v1.5 build guide, and v1.6 suggestions I read about as improvements to the kit where also included as options. Luckily 100% on the build measure trice and solder once.

 

[Jason]

Some good points about needing to measure the clear LEDs to ascertain their color. I'll make a note in the guides to test for color first.

The LEDs are standard 5mm diameter LEDs (which have an irregular flange at the base of around ~6mm). The hole in the back of the front panel is 6mm. The 1.6 kit includes two different sizes of heatshrink. Put a bit of the smaller diameter heatshrink over the 5mm part of the LED (then heat), and then the larger dia heatshrink over that, the flange and the legs (then heat). While warm and pliable this makes for a very nice press fit into the 6mm hole.

Replacement parts:

• You can buy replacement 5mm blue LEDs here
• Pack of 5mm LEDs with 7 different colors including UV?

To test the color:

• Your multimeter may have a diode test mode you can use to safely illuminate the LED
• Use a >= 1k resistor in series with a 9V battery. No resistor and you will destroy the LED.

To adjust brightness:

• Adjust using appropriate resistor value to suit
• Consider doing a mod to use the rear toggle switch as an LED dimmer switch for day/night brightness levels

 

[Skylar88]

I didn't find the directional brightness of Superbright LED's appealing and replaced it with 'regular', diffused blue LED's on my ACA.

Even after dimming with a much higher value resistor, the Superbright LED's still bugged me at night, and didn't look quite right in daytime either. Now I just love the soft blue color of the diffused LED's.

Disclaimer:
I didn't build from the diy store kit, so the above may not apply to the LED's in the kit.