It’s been a while since there’s been a “from Wisconsin” build thread, so I thought I’d get another one started.
In this discussion, I will be documenting the build of my “Best Thing since Sliced Bread” panel-mounted buffer provided by @xrk971 at XRK Audio. It is a buffer stage that can perform single-ended to balanced conversion and back. Since I’ve been trying to build a system that is balanced when possible, this was a cool tool to have in my toolbox. Details on the product can be found here:
https://www.diyaudio.com/community/threads/btsb-buffer-se-bal-to-se-bal-buffer-gb.358142/
I bought four PCBs and enough parts to create them for an upcoming project that will have four buffered inputs and could allow for either balanced or unbalanced sources. After a thorough inventory and marking of parts, I embarked upon a journey of SMD unlike any I’ve yet to experience. I read through the entire discussion above, closely reviewed the circuit boards, and the decided how I was going to attack the build.
In this discussion, I will be documenting the build of my “Best Thing since Sliced Bread” panel-mounted buffer provided by @xrk971 at XRK Audio. It is a buffer stage that can perform single-ended to balanced conversion and back. Since I’ve been trying to build a system that is balanced when possible, this was a cool tool to have in my toolbox. Details on the product can be found here:
https://www.diyaudio.com/community/threads/btsb-buffer-se-bal-to-se-bal-buffer-gb.358142/
I bought four PCBs and enough parts to create them for an upcoming project that will have four buffered inputs and could allow for either balanced or unbalanced sources. After a thorough inventory and marking of parts, I embarked upon a journey of SMD unlike any I’ve yet to experience. I read through the entire discussion above, closely reviewed the circuit boards, and the decided how I was going to attack the build.
Since this guy uses mainly 0608 package SMDs for most parts, I planned to use hot air where I could. But I started with the parts I could solder with an iron. So, I first knocked out the opamps and the voltage regulators.
After that, it was a matter of carefully selecting each set of components and making sure they went exactly where they were supposed to go. One false part placement and I was toast! Many of the parts, especially capacitors, have no markings on them whatsoever. Step by step, inch by inch, I placed each collection of parts in their respective position. Thankfully the board is very clearly marked, so parts placement was easy.
Because I don’t have a pick-and-place machine, I was soldering these components in small groups by type. So, I wasn’t using a solder paste mask or anything like that. Just dabbing and soldering. Slow and steady wins the race. The work horses for this project, the Yihua 948 solder station and Yihua 959D hot air rework station.
After that, it was a matter of carefully selecting each set of components and making sure they went exactly where they were supposed to go. One false part placement and I was toast! Many of the parts, especially capacitors, have no markings on them whatsoever. Step by step, inch by inch, I placed each collection of parts in their respective position. Thankfully the board is very clearly marked, so parts placement was easy.
Because I don’t have a pick-and-place machine, I was soldering these components in small groups by type. So, I wasn’t using a solder paste mask or anything like that. Just dabbing and soldering. Slow and steady wins the race. The work horses for this project, the Yihua 948 solder station and Yihua 959D hot air rework station.
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N00b tip: At first, I was having problems getting the solder paste to stick to the pads. It was frustrating. About halfway through the project I realized purely by accident that a little heat allowed the solder paste to stick and flow nicely. If you preheat the pads with hot air before you dab solder paste on it, it will flow right off the syringe tip and onto the pad like butter. Be careful, though, it’s easy to put on too much!
Another n00b tip: Use the lowest airflow you can with your rework station. These parts are super tiny and light and easy to blow off their pads, especially if you’re doing onesie-twosie soldering like I did here. If you’re using a reflow oven, then it’s probably a non-issue.
I placed all the SMD components over a few days. It’s tough on old eyes to work on stuff that close up for long periods of time. But I got her done. Pardon the bits of fuzz left over from my cleaning towels.
Another n00b tip: Use the lowest airflow you can with your rework station. These parts are super tiny and light and easy to blow off their pads, especially if you’re doing onesie-twosie soldering like I did here. If you’re using a reflow oven, then it’s probably a non-issue.
I placed all the SMD components over a few days. It’s tough on old eyes to work on stuff that close up for long periods of time. But I got her done. Pardon the bits of fuzz left over from my cleaning towels.
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Next it was time for the through-hole components. I was never so happy to see big parts!
Gain switches:
Input relays:
Power supply components:
Input jacks and wiring headers:
Bottom shot since we’re looking at everything:
And a fancy group photo:
I haven’t yet tested them, so will post those results here upon completion.
Gain switches:
Input relays:
Power supply components:
Input jacks and wiring headers:
Bottom shot since we’re looking at everything:
And a fancy group photo:
I haven’t yet tested them, so will post those results here upon completion.
Superb build. Great tips too. For paste application, I found that the tapered 21ga (blue) “Henna” nozzles work really well. Because they are flexible, you can apply pressure on them to flex them against the board and that pinches of the paste like a bolus. Heating the board is a good trick but too warmed and you have a puddle of paste. I made videos of how to solder using paste with these very boards here:
I also have a thread showing how to do SMT soldering of some LU1014LD1014D JFETs onto an adapter PCB bit much of the technique is the same:
https://www.diyaudio.com/community/...1014d-ims-to-247-adapter.373273/#post-6831224
Have you fired them up yet?
I also have a thread showing how to do SMT soldering of some LU1014LD1014D JFETs onto an adapter PCB bit much of the technique is the same:
https://www.diyaudio.com/community/...1014d-ims-to-247-adapter.373273/#post-6831224
Have you fired them up yet?
Nice work! I use Iwiss brand too. Mine are sideways instead of vertical. Also Amazon.
https://www.amazon.com/dp/B07476C1L...t_i_FWQZZFC3JPS6P783F9GW?_encoding=UTF8&psc=1
https://www.amazon.com/dp/B07476C1L...t_i_FWQZZFC3JPS6P783F9GW?_encoding=UTF8&psc=1
First time powering these up, so I was a bit tentative. I didn’t have a LVPS to use. My friend @dBel84 directed me to an eBay Victor +12V/+5V SMPS that I picked up for about $60US. I love this thing! I need to find another to use as a bench supply. This one is going into a project.
I got it connected and held my breath as I plugged it into the BTSB… 😰 Lights and click!
I inserted/removed my XLR adapters into the jacks and each channel’s switching relay clicked as I did so. This is a good start!
Three more devices to test…. Success! No smoke! Audio tests to go.
I got it connected and held my breath as I plugged it into the BTSB… 😰 Lights and click!
I inserted/removed my XLR adapters into the jacks and each channel’s switching relay clicked as I did so. This is a good start!
Three more devices to test…. Success! No smoke! Audio tests to go.
Nice power supply! I have something very similar from 1990’s era IBM digitizing table (4x6ft). For the BTSB, a basic 12v 1000mA SMPS or linear Class 2 wall wart actually works quite well. It has a DCDC switching supply already with an LC output filter so a linear supply input is not essential.
Not yet. Sneaking up on it. . Hopefully on Thursday or Friday night. I need to bring some gear in from the other room to test some features. I’ll do unbalanced first. That’s pretty easy.
My Aleph J is my only balanced amp, but I can probably get away with testing with my Modius DAC and Magnius headphone amp without having to bring the Aleph beast into the shop.
. Hopefully on Thursday or Friday night. I need to bring some gear in from the other room to test some features. I’ll do unbalanced first. That’s pretty easy. My Aleph J is my only balanced amp, but I can probably get away with testing with my Modius DAC and Magnius headphone amp without having to bring the Aleph beast into the shop.