that's good.
Hi,
So I built two of the ACA’s hoping to use them in mono. I had a few problems but you guys were able to straighten me out and everything seemed fine. I connected and tried both amps to some old speakers I had laying around and everything seemed fine. This was several months ago. I was waiting for my speakers to arrive and this is my secondary system so the amps just sat there. My new speakers arrived and I hooked everything up and now Everything has gone to hell. I have much more volume from one amp then the other amp. As a matter of fact one amp is barely audible. I tried switching speakers since the speakers were new and tried switching speaker cables in case something is wrong with the cables and nothing the volume on one amp is much higher than the other amp. So, any ideas before I tear everything apart and compare everything including settings. So you know my set up in case it’s relevant. Zu Audio Omen Dirty Weekend speakers, Schiit Valhalla pre-amp, Denafrips Ares II DAC and a BlueSound Nide 2i as a source.
Helpppppp!!!
So I built two of the ACA’s hoping to use them in mono. I had a few problems but you guys were able to straighten me out and everything seemed fine. I connected and tried both amps to some old speakers I had laying around and everything seemed fine. This was several months ago. I was waiting for my speakers to arrive and this is my secondary system so the amps just sat there. My new speakers arrived and I hooked everything up and now Everything has gone to hell. I have much more volume from one amp then the other amp. As a matter of fact one amp is barely audible. I tried switching speakers since the speakers were new and tried switching speaker cables in case something is wrong with the cables and nothing the volume on one amp is much higher than the other amp. So, any ideas before I tear everything apart and compare everything including settings. So you know my set up in case it’s relevant. Zu Audio Omen Dirty Weekend speakers, Schiit Valhalla pre-amp, Denafrips Ares II DAC and a BlueSound Nide 2i as a source.
Helpppppp!!!
Be sure that the switch on both amps is set to Bridged Mono (flipped in the Upward position). It's very easy to flip the switch out of the Bridged Mono position.
Also, check connections to the binding posts of the speakers cables for a bridged mono configuration for each amp and speaker is also correct, including the polarity of each speaker cable. Examine the diagram on the back carefully and make connections of each channel's speaker cable, the - and the + leads, to the correct binding post. It's easy to connect them incorrectly, so examine the diagram for a bridged mono configuration carefully.
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Hi again, well I tried running them both on Stereo. The amp that I was getting good sound out of was fine in Stereo. The other amp with the volume problem one of the channels had no sound. Switched speakers and problem remained.
So I am thinking I have a wiring problem?
Thanks,
J
I had actually tried all that and nothing but I think I wired something wrong.
At least you know which board / channel is the problem and where to focus.
80% plus of the ACA faults are poor soldering or wiring problems.
On the 'bad' channel check for shorted output and input sockets:
Check the resistance from the Red to Black speaker socket. It should be 500Ω to 1kΩ.
With the rear switch in the central position, check the resistance from the outer ring of the RCA socket to the centre pin. It should be about 50kΩ.
Check the 'good' channel for comparison.
Do both the 2 big transistors (Q1 and Q2) get hot?
Are you able to set the 'bias' to 12 volts?
What was the problem (you mentioned) that required forum help with before?
Post some good pictures of the faulty side board and wiring if you can.
Also have a look at the troubleshooting section of the v1.6 build guide. Amp Camp Amp V1.6 Build Guide - diyAudio Guides
Alan
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Need help please!
Good evening,
So I just finished the ACA 1.8 project and I need some help troubleshooting why it isn't working.
I am not sure where I made the mistake, but here is what I know so far:
I measured every resister meticulously before soldering.
When powering on the amp, only the right diode lights up. I don't think its the diode since the output voltage on the PCB at +LED- measures 0. The other one which works correctly is measuring 2.56v.
Both cooling rips heat up evenly, so I suspect the transistors are receiving power.
Hoping for some insights into my errors!
- Dan
Good evening,
So I just finished the ACA 1.8 project and I need some help troubleshooting why it isn't working.
I am not sure where I made the mistake, but here is what I know so far:
I measured every resister meticulously before soldering.
When powering on the amp, only the right diode lights up. I don't think its the diode since the output voltage on the PCB at +LED- measures 0. The other one which works correctly is measuring 2.56v.
Both cooling rips heat up evenly, so I suspect the transistors are receiving power.
Hoping for some insights into my errors!
- Dan
Hi Dan,
As Rafa says is it just he LED not working or more? Like no sound from one or both channels?
Could you set the DC balance' on both channels to 12 volts as per the build guide? (Amp Camp Amp V1.6 Build Guide - diyAudio Guides)
Have you got +24 volts going to both boards? Check between the V+ and GND pads on the boards.
Most faults are poor soldering, then parts in the wrong place or wrong way round. Post some good pictures of the boards and wiring so we can see and help.
And please be more specific as to the problem(s).
Alan
Anyone using any taller, aftermarket feet that screw into the stock holes? I am still building mine but from what I've read, it sounds like it will benefit from being raised a bit for heat. I'm also not fond of stick on feet, especially when heat is involved.
Attachments
Is this what you're referring to?
I was hoping to find some that just replace the screws to fasten the bottom of the case and double as higher feet. Are these specific feet a common mod? The description of these feet is as follows:
"You will need to drill your own holes in your cover for the bolts to be inserted into. This gives you the option to have a standard 4 feet layout, or a 3 feet "tripod" arrangement that is immune from rocking, further improving stability, while not having any extra holes in your cover you don't need."
Yep - look a bit chunky on the ACA but do get it high enough for good ventilation.
I am a bit confused if you are talking about the "other" First Watt amps that actually use 300VA transformers? The ACA is, more often than not, driven by a SMPS 24V 5A PSU (this one: Meanwell 24V 5A power supply and power cord – diyAudio Store )
Still, consider that the 10W of the V1 is more like 8W per channel now in the newer versions of the ACA. That said, that is the power it can deliver to the speakers, but it is NOT the power it draws from the wall. There is a lot of heat dissipation, hence the need for the beefier PSU.
Still, you are probably referring to the "other" amps and not the ACA which is not very often driven by linear PSUs.
Rafa.