Drip opto 7 stereo build ... Problems ..

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Vientos00

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Joined
Jun 12, 2019
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14
Hi guys. Im new to the forum and just started my drip opto 7. obviously in already have some questions for some of you salty guys one here. Im just now getting my parts together. Got my shopping cart on Digi-Key ready. Thing is though some of these resistors are either discontinued or have to be ordered in bulk. I think I found a way around it but I don't want to screw it up. For example the parts list calls for a 470K res 1/2W 5%,
but the brand that comes up on the instructions is ohmite. That one is not available for 5 months?! lol. Can I use any other through hole resistor as long as the specs are the same even if its a different brand? also does the composition of the said resistor have to be identical to the one in the opto 7 guide? Sorry if this is a stupid question. If I can use other brands than im good other than the fact that I can't find the gray hill rotary switch anywhere...Anyone here know what other rotary switches I can use besides the gray hill? I believe it calls for 4 rotary switches 2-6 pos 250MA 115V. im assuming that this is for the input and reduction knobs. Anyone know which other ones I can use besides the gray hills? I can't start this build till find these switches lol Thanks
 
Any resistor with correct vallue and power rating will work.

Sometimes precission resistors are prefered on input pads to keep L and R the same or to keep all the steps at exactly 1dB.

For the rotary switches maybe check Lorlin switches.
 
Welcome to the board!

On the switch thing, Grayhill are in short supply everywhere right now due to the pandemic. The key question (and I'm not familiar with this project) is whether the switches are PCB mount, or solder tag.

If they're solder tag, then you should be able to substitute something else such as a Lorlin / Blore Edwards etc, as long as there's physically space in the front panel layout and you choose the right contact form (shorting / non-shorting). You'd need to take account of other factors in your front panel design and knob selection - that might include bushing diameter and length, shaft diameter and length, and such.

If the switches are PCB mount then I'm not aware of any other switches that are the same pin spacing as Grayhill. You might be able to get round it by wiring up a solder-tag switch off board, but that might compromise something mechanical (again, I'm not familiar with this project so you'd need to take a view on that).

Hope that helps!
 
Thanks a lot. I really appreciate it. Ive built mics and stuff before but never a compressor. If anyone out there has any tips on calibration or special precautions that i should take please feel free to chime in.
 
In this latest stereo version the front panel switches are mounted to a PCB strip, much like drips EQP1A design.  You certainly can use other switches - you just have to know how to wire them up, but you'll lack the neatness of that nice PCB mount.
I built an older version drip EQP back in Jan and sourced these parts from onlinecomponents.com in Chicago.  You have to buy a min of two, but that's fine for you - you need a total of 4!  The only difference with these is that the shaft diameter is smaller.
Otherwise they are a drop in replacement.
https://www.onlinecomponents.com/en/grayhill/71adf30012ajn-11455575.html
Don't be fooled by the image on the page - these have a single deck of pins, as noted in the specs below the image.
 
How the heck do you mount the XLR's to the rear of the case? The v7 Drip docs appear to show a PCB mount in one section of the PDF, but there is apparently no PCB depicted for that in other sections of the PDF,  where it shows all that is included (main PCB and front panel PCB).  I assume you have the PCB's already. 
The reason I'm asking is because all these PCB mounts make having a precision cut case an absolute must.

Edit:  googling for images I see there is a PCB that mounts the PSU and 4 XLR's to the rear of the case. 
 
TwentyTrees said:
Welcome to the board!

On the switch thing, Grayhill are in short supply everywhere right now due to the pandemic. The key question (and I'm not familiar with this project) is whether the switches are PCB mount, or solder tag.

If they're solder tag, then you should be able to substitute something else such as a Lorlin / Blore Edwards etc, as long as there's physically space in the front panel layout and you choose the right contact form (shorting / non-shorting). You'd need to take account of other factors in your front panel design and knob selection - that might include bushing diameter and length, shaft diameter and length, and such.

If the switches are PCB mount then I'm not aware of any other switches that are the same pin spacing as Grayhill. You might be able to get round it by wiring up a solder-tag switch off board, but that might compromise something mechanical (again, I'm not familiar with this project so you'd need to take a view on that).

Hope that helps!

Oh boy. You may encounter some trouble if you don't know that you can use any resistor with the correct resistance, wattage, and tolerance. I'm not trying to discourage you, but I worked forever on my Dual Sta Level and I found the lack of explanation of the universal PSU, the lack of schematic, and the small problems that arose that were unexplained very stressful. I'd approach this whole project very slowly. Watch videos on proper soldering and PCB cleaning and how to properly work with high voltages. Drip builds are never as straight forward as they're presented in my experience.

Also, if the universal PSU is like the one in mine, the XLR's are mounted on one side of psu and then the PSU/XLR's are mounted on the back panel.
 
Im going to work on it very slowly. Im actually enjoying the learning part.Ive built mics and stuff before but they were "all included Kits" so I wasn't to sure if the brands of resistors effect the build or not yet. Whole new world ya know. But I'm enjoying it. This is my first Drip audio. Speaking of the PSU that's another question that I have. Are they supposed to be all universal now with the Errata update where your supposed to use the diodes instead of the rectifier tube like on the STA level ? Or is the Opto 7 different from the Sta? Im asking cause the docs from the opto 7 tell you to mount the tube and the docs from the STA tell you to skip it and use diodes instead. If this is so than how is the PSU "universal"? Sorry if its a dumb question
 
Its a universal psu in that one pcb can power different devices with minor component changes with each build. There is literally no reason to look at the sta level build you're just going to confuse yourself further. They have completely different voltages. Focus on the opto manual.
 
For the OPTO 7, if you're building a stereo unit all in the same box, only ONE PS is needed to power both channels.  That being said, I'd select the diode (not tube) power supply for better performance.
The opto v7 docs I read, like all drip designs, let you select either tube or diodes in the PS.  I've always used diodes and never had an issue.
 
The STA uses the diodes because, according to Gregory, using the tube will cause overheating issues in that build.  For the Opto, it seems you have the choice of either.  I personally might agree with dbonin here and say go with the diodes, if for no other reason than I’ve heard complaints of new production 5ar4 tubes having a fairly short lifespan (can’t speak to it myself), and NOS can be frustratingly expensive.
 
Also far as the gray hill switches Ive noticed that they are adjustable. so it doesn't matter if its a 2-6 pos switch or if its a 12 pos switch cause the 71 series can be adjusted either way...right?
 
The reason why I am so confused with this Drip Opto 7 build is because mine has one of the NEW psu's. The problem is that in ALL of the documentation for the build of the Opto 7 psu, IT STILL HAS THE OLD PSU INSTRUCTIONS! lol. This one has 2 new fuse holders and a 470 bleed where the "no choke" used to be. The STA level documentation however does have the updated PSU designs. So WHICH am I supposed to follow? And how am I supposed to follow the Opto 7's PSU instructions when they are outdated...My PSU board is just different than the one in the instructions. So what am I supposed to do here....
 
The reason why I am so confused with this Drip Opto 7 build is because mine has one of the NEW psu's. The problem is that in ALL of the documentation for the build of the Opto 7 psu, IT STILL HAS THE OLD PSU INSTRUCTIONS! lol. This one has 2 new fuse holders and a 470 bleed where the "no choke" used to be. The STA level documentation however does have the updated PSU designs. So WHICH am I supposed to follow? And how am I supposed to follow the Opto 7's PSU instructions when they are outdated...My PSU board is just different than the one in the instructions. So what am Isupposed to do here....
since the specs of the opto 7 state max. 34mA or was it 37mA current ... the Hammond 157 H Choke could be an option and it fits inside the box and is rated 10mH @Max 50mA ... thats what i am gonna do. No harm to the rect tube and you can add the jumper as stated on the 2020 psu board.

my first post, hope it helps ya
 
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Im pretty much done with the build. Anyonw here know how or where to hook up the bypass and link switches? Also what kind of calibration am I looking at ? I calibrated my 1176 and that wasnt hard at all. Any advice?
 
I finally figured out that I had the vu meter hooked up right. It was a cheap meter that had the wrong specs so ill be ordering a different one here soon. As for the bypass and link switches I think that you plug in an SMA and cut the other end and wire those 2 halves to the switch.. I think. We'll see. If any one else here know the answer feel free to chime in . peace
 
Hi... My Build of the Opto7 is almost done. The bypass switch is connected as followed. You have to connect the 6.3V of your Power PCB over a Switch to the Sma Bypass connector.

Greetings Cream
 
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