[BUILD] FET/500 Official Support Thread

[MChammer]

I looked into that area on the board. I found nothing on closer examination I found that I had switched the .22 uF capacitors with the 220 pF capacitors. I made a careless mistake when moving decimals, I should have wrote it down. I believe this may be causing my issue. I broke one of the 220 pF ceramic capacitors when removing it, so I ordered some more. They should be in on Thursday or Friday. I have my fingers crossed that once I get the capacitors in the correct places that the calibration and LEDs will behave correctly. (Its weird that the voltage outputs are correct while the LEDs are not).  Anyway I'll let you know how things go. I am using  Rev A and D for my final directed project/dissertation for my masters.

-Thanks for all the help so far! 

 

[cryptokoan]

Hey yall,

Just built a stereo pair of the REV A....sounds awesome!!

One thing I was wondering about.. When I run them into a line mixer, I get very faint clicks that correspond to the gain meter led moving, on both compressors.

However when I run them straight into my converters I get no such problem. Is this a problem with my line mixer? Im just wondering why it would seem to correspond with the fet500 gain meter. Grounding issue?

The clicking is ever so faint,  and only happens when the led is moving. If gain remains below -20 there is no clicking. Any ideas?

-eric

 

[Echo North]

Hey yall,

Just built a stereo pair of the REV A....sounds awesome!!

One thing I was wondering about.. When I run them into a line mixer, I get very faint clicks that correspond to the gain meter led moving, on both compressors.

However when I run them straight into my converters I get no such problem. Is this a problem with my line mixer? Im just wondering why it would seem to correspond with the fet500 gain meter. Grounding issue?

The clicking is ever so faint,  and only happens when the led is moving. If gain remains below -20 there is no clicking. Any ideas?

-eric

That's super weird. Sorry I don't have any idea about that one.

 

[justinheronmusic]

Everything is plugged in and passing signal. But here are a few of my issues.

1) Gain Reduction Meter is always on, and doesn't move regardless of signal being present.
2) Can't seem to calibrate the +16dbu peak LED.

Other than that I seem to be doing pretty ok. Has anyone else had this issue,  and can you give me guidance as to where to look for errors?

 

[Echo North]

Everything is plugged in and passing signal. But here are a few of my issues.

1) Gain Reduction Meter is always on, and doesn't move regardless of signal being present.
2) Can't seem to calibrate the +16dbu peak LED.

Other than that I seem to be doing pretty ok. Has anyone else had this issue,  and can you give me guidance as to where to look for errors?

1) Even attempting to calibrate it does nothing? Is it in BAR or DOT mode?
2) Can you calibrate the +4/0?

Mike

 

[justinheronmusic]

I've got the GR meter in BAR mode. When I touch the stereo link jack with my finger the GR meter LED's turn off. At the moment the only thing I can calibrate is the Q Bias and the VU Trim.

- No matter how far left or right I turn the Gain Trim, the Peak LED doesn't turn off. If I back the output down to 3.88 or so, then the peak LED turns off as if I have the correct signal. I'm running a -11.9 signal from Pro Tools Signal Gen, which gave me 0.775 VAC, out of an Apollo Twin Solo into the Lindell 503 rack, and measuring at pins 2 & 3 of the XLR.

 

[Echo North]

I've got the GR meter in BAR mode. When I touch the stereo link jack with my finger the GR meter LED's turn off. At the moment the only thing I can calibrate is the Q Bias and the VU Trim.

- No matter how far left or right I turn the Gain Trim, the Peak LED doesn't turn off. If I back the output down to 3.88 or so, then the peak LED turns off as if I have the correct signal. I'm running a -11.9 signal from Pro Tools Signal Gen, which gave me 0.775 VAC, out of an Apollo Twin Solo into the Lindell 503 rack, and measuring at pins 2 & 3 of the XLR.

It's go over the meter PCB.  Double check all the component values and reflow and suspect joints. 

 

[Echo North]

Also, remember for the GR meter a lot of that circuitry is on the main PCB around that IC.  Have a good look at that, if you're having trouble calibrating.

 

[justinheronmusic]

Also, remember for the GR meter a lot of that circuitry is on the main PCB around that IC.  Have a good look at that, if you're having trouble calibrating.

Checked all my values around the Main PCB IC, and the Meter Board. Everything seems to be in order.  I reflowed questionable solder joints.

I took the GR meter out of BAR mode, and the GR meter is no longer constantly illuminated, but the SLAM light is always on regardless of ratio. Also still having issues with the peak indicator LED, at 4.88 it's always illuminated regardless of the trim pot setting. 

 

[Echo North]

Also, remember for the GR meter a lot of that circuitry is on the main PCB around that IC.  Have a good look at that, if you're having trouble calibrating.

Checked all my values around the Main PCB IC, and the Meter Board. Everything seems to be in order.  I reflowed questionable solder joints.

I took the GR meter out of BAR mode, and the GR meter is no longer constantly illuminated, but the SLAM light is always on regardless of ratio. Also still having issues with the peak indicator LED, at 4.88 it's always illuminated regardless of the trim pot setting.

You GR meter in BAR should illuminate and then un-illuminate with GR think of it like the classic 1176 meter?  In dot 0 just should be lit. So calibrating it does nothing? The GR meter doesn't change?

Try setting your pots to the center. Turn till they "click" then rotate back the other way 10 turns and try to set that GR meter.

Mike

 

[justinheronmusic]

I've got the GR meter in BAR mode. When I touch the stereo link jack with my finger the GR meter LED's turn off. At the moment the only thing I can calibrate is the Q Bias and the VU Trim.

- No matter how far left or right I turn the Gain Trim, the Peak LED doesn't turn off. If I back the output down to 3.88 or so, then the peak LED turns off as if I have the correct signal. I'm running a -11.9 signal from Pro Tools Signal Gen, which gave me 0.775 VAC, out of an Apollo Twin Solo into the Lindell 503 rack, and measuring at pins 2 & 3 of the XLR.

It's go over the meter PCB.  Double check all the component values and reflow and suspect joints.

After setting the zero adjust to the middle position, GR Meter is functioning, I was able to zero adjust properly. Here are my current issues:

-  @4.88 output and peak LED is always on despite the Gain Trim pot.
- Tracking adjust doesn't affect GR meter

 

[justinheronmusic]

Ok, I successfully calibrated the GR tracking. You were right, it was the position of the trim pots. I reset them all and it did wonders for the calibration process.

Still lost on the Peak indicator LED though. That's still not working for me.

 

[mnats]

Still lost on the Peak indicator LED though. That's still not working for me.

Check all the usual things listed in the General Troubleshooting page linked from the first post of this thread. Report back after you've done so.

 

[Sinkia]

Hi Mike

We have order a fet500 revA over here on France ! I'm currently building it.
It appears alle the screws & standoff are missing from the boxes.
Is it an error from yours or de has to buy it separatly? (I gave check on the élément Copper we bought to, thosese screws & standoff are inside)

 

[Echo North]

Hi Mike

We have order a fet500 revA over here on France ! I'm currently building it.
It appears alle the screws & standoff are missing from the boxes.
Is it an error from yours or de has to buy it separatly? (I gave check on the élément Copper we bought to, thosese screws & standoff are inside)

No they should be in there. 

Do a full inventory and send us a list of what you're missing to "info (at) hairballaudio (dot) com".

Thanks!

 

[mhbunch]

Hey Mike,

I have a super weird issue. I built a rev A in January and it was working great and sounding KILLER until last week all of a sudden it just stopped working. I turned on my lunchbox and the "slam" light was always lit no matter what position i had the ratio on. When I tried running audio it wasnt compressing. I took it out and checked all solder points thinking it might be a short and touched up a few spots that seemed mayybe questionable but overall its a pretty clean job. Put it back in the lunchbox and now the slam light isnt lit but it still wont compress at all. All other functions work ( input, output, gr off [no saturation tho], bypass).

Any clue what might be going on? Maybe one of my trimmers fried?

thanks!

Mackenzie

 

[Echo North]

Hey Mike,

I have a super weird issue. I built a rev A in January and it was working great and sounding KILLER until last week all of a sudden it just stopped working. I turned on my lunchbox and the "slam" light was always lit no matter what position i had the ratio on. When I tried running audio it wasnt compressing. I took it out and checked all solder points thinking it might be a short and touched up a few spots that seemed mayybe questionable but overall its a pretty clean job. Put it back in the lunchbox and now the slam light isnt lit but it still wont compress at all. All other functions work ( input, output, gr off [no saturation tho], bypass).

Any clue what might be going on? Maybe one of my trimmers fried?

thanks!

Mackenzie

Doubt it's a trimmer. If anything failed, it would be something like a transistor or diode.  Some times it's a bad point or some connection is loose.

Mike

 

[mhbunch]

Hey Mike,

I have a super weird issue. I built a rev A in January and it was working great and sounding KILLER until last week all of a sudden it just stopped working. I turned on my lunchbox and the "slam" light was always lit no matter what position i had the ratio on. When I tried running audio it wasnt compressing. I took it out and checked all solder points thinking it might be a short and touched up a few spots that seemed mayybe questionable but overall its a pretty clean job. Put it back in the lunchbox and now the slam light isnt lit but it still wont compress at all. All other functions work ( input, output, gr off [no saturation tho], bypass).

Any clue what might be going on? Maybe one of my trimmers fried?

thanks!

Mackenzie

Doubt it's a trimmer. If anything failed, it would be something like a transistor or diode.  Some times it's a bad point or some connection is loose.

Mike

Could you point me in the right direction to start poking around? The unit still passes audio when engaged and the input and output effect the signal level, the output meter works but no leds in the gr meter are lighting

 

[Echo North]

Hey Mike,

I have a super weird issue. I built a rev A in January and it was working great and sounding KILLER until last week all of a sudden it just stopped working. I turned on my lunchbox and the "slam" light was always lit no matter what position i had the ratio on. When I tried running audio it wasnt compressing. I took it out and checked all solder points thinking it might be a short and touched up a few spots that seemed mayybe questionable but overall its a pretty clean job. Put it back in the lunchbox and now the slam light isnt lit but it still wont compress at all. All other functions work ( input, output, gr off [no saturation tho], bypass).

Any clue what might be going on? Maybe one of my trimmers fried?

thanks!

Mackenzie

Doubt it's a trimmer. If anything failed, it would be something like a transistor or diode.  Some times it's a bad point or some connection is loose.

Mike

Could you point me in the right direction to start poking around? The unit still passes audio when engaged and the input and output effect the signal level, the output meter works but no leds in the gr meter are lighting

Do you have two of them? If you do swap the meter PCBs and see if the issue follows the meter PCB.

If you only have one, look at the meter PBC and re-seat it.

Mike

 

[zarndyhoff]

Hey Mike (or anyone that can offer advice),

I bought a pair of FET500 rev D kits, first one works great, second one not so well.

I've checked and rechecked the solder points, and I've gone through the BOM and verified that each resistor is correct. I've verified that each polarised cap is facing the right way, and that all diodes are facing the right way.

My problematic 1176 is making 'starved voltage' sounds and requires unreal amounts of input gain to register any signal at the output (there don't seem to be any issues with the input registering signal). However, at the output it's making clipping and farting noises.

Here are two videos I made detailing the symptoms. The first video shows the output gain problems, and the second video shows the noise my unit makes.

Apologies for my New Zealand accent!!

Thanks, Alex Harmer.

https://www.youtube.com/watch?v=o9RC4MRNCqg

https://www.youtube.com/watch?v=DqILqkZGpfQ