Just try connecting the trigger pin 18 on P102 with DVDD pin 11, which is a 5V output. Even if standby is activated, the trigger should override it. Leave the P101 plug off.
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11.5.7 Trigger Input
When the 1200AS is in standby-mode set by a high on the Standby input, the module can be powered up by a high on
the Trigger input. This can e.g. be used to switch on and off a remotely located amplifier. Figure 26 shows how the
Trigger and Standby inputs are gated together with the SignalSense input. Please read Section 11.5.8 on more
information on SignalSense.
Figure 26: Standby, Trigger and SignalSense input overview
The Trigger input is designed to work correctly with standard logic circuits. However, it is tolerant to higher input
voltages allowing it to be used directly as e.g. 12 V trigger in AVR applications or subwoofers.
Page 32
11.5.7 Trigger Input
When the 1200AS is in standby-mode set by a high on the Standby input, the module can be powered up by a high on
the Trigger input. This can e.g. be used to switch on and off a remotely located amplifier. Figure 26 shows how the
Trigger and Standby inputs are gated together with the SignalSense input. Please read Section 11.5.8 on more
information on SignalSense.
Figure 26: Standby, Trigger and SignalSense input overview
The Trigger input is designed to work correctly with standard logic circuits. However, it is tolerant to higher input
voltages allowing it to be used directly as e.g. 12 V trigger in AVR applications or subwoofers.
@von Ah
I appreciate your concern! I don't believe the wires have anything to do with my issue, as I have unplugged them from the module and the issue is still there. Btw, I see you also build amp kits? I was thinking about building another amp, but undecided which amp I could build to give me the best sonics. I've looked at the purifi build, but not really sure how much better it can sound over my old Acurus DIA100, that was modified. Comparing the Acurus to the 1200as2 is a subjective opinion, but they both do things good in certain areas of sonics. In your honest opinion, which amp have you built that has the best overall sound? Thanks!!!
I appreciate your concern! I don't believe the wires have anything to do with my issue, as I have unplugged them from the module and the issue is still there. Btw, I see you also build amp kits? I was thinking about building another amp, but undecided which amp I could build to give me the best sonics. I've looked at the purifi build, but not really sure how much better it can sound over my old Acurus DIA100, that was modified. Comparing the Acurus to the 1200as2 is a subjective opinion, but they both do things good in certain areas of sonics. In your honest opinion, which amp have you built that has the best overall sound? Thanks!!!
@hifiamps
I have connected the pins you told me to connect and when first powering up the amp both LED's light up and then I hear that noise(perhaps the relay?) and the blue ON light comes on and stays on. So now after a couple of minutes, I heard that relay or whatever noise it is. Not sure if this is going to work? I was hoping I would not hear that noise again. Note that I did not connect any other components to the amp, I just turned it on to see what would happen. So far after several minutes, that noise sounded twice, but the blue LED is still glowing..lol
I have connected the pins you told me to connect and when first powering up the amp both LED's light up and then I hear that noise(perhaps the relay?) and the blue ON light comes on and stays on. So now after a couple of minutes, I heard that relay or whatever noise it is. Not sure if this is going to work? I was hoping I would not hear that noise again. Note that I did not connect any other components to the amp, I just turned it on to see what would happen. So far after several minutes, that noise sounded twice, but the blue LED is still glowing..lol
Best overall sound is difficult to choose. I’ll split it up by class:
- Class A
- @Zen Mod Scryer
- @Nelson Pass F5 with 2SK1530 / 2SJ201
- Class AB
- @tomchr Modulus 86
- @Bob Cordell DH-220C
- Class D
- @abraxalito MonoAmps
- IcePower 300A2
The main system doesn’t lie. I’ve had the Scryer in my main rig the most since I built it.
@von Ah
Is this Scryer amp build something still available? I'd like to try and build something like this. Any idea what the parts would cost without chassis, wire, connectors and such? BTW, I have 2 pure class A mono tube amps I tweaked, so not sure how they would compare to the SS class A amp?
Is this Scryer amp build something still available? I'd like to try and build something like this. Any idea what the parts would cost without chassis, wire, connectors and such? BTW, I have 2 pure class A mono tube amps I tweaked, so not sure how they would compare to the SS class A amp?
Try the jumper from P101 pin 4 (GND) to pin 6 (standby) and see if that stops standby.
@hifiamps
So do I leave the connector for P102 on the module and connect pin 4 to pin 6 on P101? The standby (amber LED) only comes on together with the blue LED ON when the amp is first powered up, then within like a second or two, the amber LED goes off but the blue LED ON stays lit. But after a few minutes I can still here that click/buzz like noise. So evidently there is still something wrong.
I'll try what you say about connecting pin 4 with pin 6 on P101, just needed to know if I should disconnect the connector on P102 or leave it connected? Thanks!
So do I leave the connector for P102 on the module and connect pin 4 to pin 6 on P101? The standby (amber LED) only comes on together with the blue LED ON when the amp is first powered up, then within like a second or two, the amber LED goes off but the blue LED ON stays lit. But after a few minutes I can still here that click/buzz like noise. So evidently there is still something wrong.
I'll try what you say about connecting pin 4 with pin 6 on P101, just needed to know if I should disconnect the connector on P102 or leave it connected? Thanks!
You'd have to contact Zen Mod via PM to find out about board availability for the Scryer. Mind you that's if you have or can readily get a couple Tokin SIT devices.
I'd suggest you start with something a bit simpler (ACA Mini, MoFo, Aleph J, check the diyaudio store for availability) if you want to get aquainted with solid state class A. How do you like your tube amps? How much output power do you really need? The 1200AS you're using is quite a beast. If you need a ton of power, class A is out of the realm of sanity.
I'd suggest you start with something a bit simpler (ACA Mini, MoFo, Aleph J, check the diyaudio store for availability) if you want to get aquainted with solid state class A. How do you like your tube amps? How much output power do you really need? The 1200AS you're using is quite a beast. If you need a ton of power, class A is out of the realm of sanity.
Leave the pin 18 to 11 jumper on P102 connected, because that keeps the amp powered (blue LED). Now trying to keep standby from activating.
I am not trying to fix your amp. Just trying to get it into a functional state.
Have you connected input and speakers (test speakers)?
OK so I left P102 connected as you said and connected pins 4 & 6 on P101. Powered the amp on, both LEDS come on then the amber standby went off, then a few seconds later, the amber LED came back on then went off. It appears that didn't help the issue. Anything else I can try besides striping the copper out..lol
Listen to it. Is the standby switching on and off affecting the audio output or is it just creating noise from the relay switching?
Locating the relay would help. Use a long plastic straw, get it close to the board and listen to where you think the relay is. Be careful and keep your body well clear of the PCB.
Since there aren't schematics for these amps, reverse engineering the standby circuit and identifying the problem would be the only option for actually fixing the amp.
Locating the relay would help. Use a long plastic straw, get it close to the board and listen to where you think the relay is. Be careful and keep your body well clear of the PCB.
Since there aren't schematics for these amps, reverse engineering the standby circuit and identifying the problem would be the only option for actually fixing the amp.
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@hifiamps
Ok, so I hooked it back up to play music. It started out playing but after like a minute, it goes in standby mode, then starts playing again and keeps this cycle, so I turned it off. I agree with you that there aren't any schematics for this module 🙁 So I thought maybe I could use a pencil and place the rubber side on where I think this relay is? I can perhaps feel the vibration, but not sure that would be a good idea. I will try the straw to see if I hear it. I'll report back when I find out. Thanks again for your patience with trying to help me! 👍
Ok, so I hooked it back up to play music. It started out playing but after like a minute, it goes in standby mode, then starts playing again and keeps this cycle, so I turned it off. I agree with you that there aren't any schematics for this module 🙁 So I thought maybe I could use a pencil and place the rubber side on where I think this relay is? I can perhaps feel the vibration, but not sure that would be a good idea. I will try the straw to see if I hear it. I'll report back when I find out. Thanks again for your patience with trying to help me! 👍
So I believe I have found where this click/buzz noise is coming from. Appears to be a transformer for the power supply? Not sure. I circled it in red that says CLICKING NOISE
From looking at other pictures, I think the relay is the box under all the glue at the bottom of your picture. It would be useful to know if the amp is going into protect mode. Pin 12 on P101 indicates that (designed to drive an LED). It may be acting appropriately based on some other problem (like PSU) it is detecting. Check the temp of the four large brown PSU caps with an infrared thermometer. If one of the caps is failing, that could cause a shutdown. PSU caps going bad is a common problem.
From an Apollon Audio post in ASR: "From around 200 installed 1200as2 modules 20 of them failed."
From an Apollon Audio post in ASR: "From around 200 installed 1200as2 modules 20 of them failed."
@hifiamps
I'm not sure if a relay is located under that box with the glue but I never felt anything in that area like I felt on that transformer when I used a pencil with the rubber/eraser side. I'm certain that is where that clicking/buzz noise is coming from. So I do have a digital infrared thermometer, so I am assuming to try and play music while seeing the temps? Should I try and crank up the volume some to get the transistors warm?
I'm not sure if a relay is located under that box with the glue but I never felt anything in that area like I felt on that transformer when I used a pencil with the rubber/eraser side. I'm certain that is where that clicking/buzz noise is coming from. So I do have a digital infrared thermometer, so I am assuming to try and play music while seeing the temps? Should I try and crank up the volume some to get the transistors warm?
The transformer can buzz, but not click. I could see that the transformer buzzes due to a high duty cycle, trying to maintain voltage, because one or more of the caps is bad. Then the standby relay clicks in protect mode turning off the high voltage supply. The cycle repeats.
You don't need to play music. Check the temps of the caps with the amp on. If one or more is high temp, I would replace all 4.
You don't need to play music. Check the temps of the caps with the amp on. If one or more is high temp, I would replace all 4.
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