500/51X Series SLQ51X SSL styled 4000 EQ / Filter

[Kevin]

Hello. I'd like to start by saying I'm loving the browny i recently built (Considering a second)

I have noticed a curious phenomenon that possibly has an easy explanation. Hoping someone here might instantly know what is occurring.

When I send a line level signal into the CAPI VP28 and then into the LINK. There is a big difference in signal when toggling bypass on the LINK... ~ 10db. I have 2 vp28s and they both do the same thing. I tried different cables, same result.
When i send the signal straight to the LINK the bypass works as intended.

Any ideas?.. cheers

With the unit bypassed, you should have same level as send in to the unit. So this sounds like one of the Relays is maybe not switching. Check all Diodes if they work and then if both relays are click when switching. The unit itself when its on, should not do any gain - the tolerance is around 0.5 dB difference.

 

[Cockola]

With the unit bypassed, you should have same level as send in to the unit. So this sounds like one of the Relays is maybe not switching. Check all Diodes if they work and then if both relays are click when switching. The unit itself when its on, should not do any gain - the tolerance is around 0.5 dB difference.

Thanks for the quick reply. When i go straight from interface to EQ the bypass works perfectly. It only changes when I put a VP28 in between.

I should probably have mentioned that when configuring the LINK I accidentally inserted the unit (badly) into the chassis while it was powered, which fried RP6. Maybe I killed something else as well.

I will try to work out how to best test these things.

thanks

 

[SKJGProject]

Still haven’t decided if i should go for stock HP/LP freq or use a different frequency…..any suggestions?

 

[z11111]

Hi all,

Ordered these a while ago from Kevin and finally finished building them out and have used them on a couple of mixes. Ran into 0 problems during the building process — instructions were so detailed and easily one of the best DIY kits I’ve ever built! Calibration was super simple and they’re doing a fantastic job on kick drum and bass guitar. A+ would highly recommend.

thanks for a great product, Kevin!

 

[minor_glitch]

Hey, quick question. Just got a pair of the black kits through DIYRE and I'm wondering which version of the build guide to use. Rev A and rev B both show photos of the rev A boards.

Also, the rev A guide says to leave out C6 and shows it crossed out. The Rev b guide uses the same photo of C6 crossed out (bottom of pg3), but doesn't say to leave it out. Wrong photo?

Thanks!

 

[Kevin]

yes the pictures in REV B guide are wrong. I already doing the soldering for the pictures to change them In REV B there are just the parts you need, nothing leaving out .

 

[andYz00m]

Just grabbed a pair of the Rev B SLQ51X Black. Super excited to build them!

I also saw that you are taking preorders for a Neumann W492... I might grab a pair of these as well once IM done with the SLQ

W92X | Link Audio Design

 

[pkuchar]

I fried one of the switches does anyone know the part number, lots of different types.
Thanks

 

[andYz00m]

Hey there, just built a pair of these and one works perfectly, the other works fine for the most part but when I toggle the HPF there is a huge low frequency hum on output.

Any ideas of where to look?

 

[Kevin]

I fried one of the switches does anyone know the part number, lots of different types.
Thanks

It's a Alps Spuj190900

 

[Kevin]

Hey there, just built a pair of these and one works perfectly, the other works fine for the most part but when I toggle the HPF there is a huge low frequency hum on output.

Any ideas of where to look?

Did you calibrated the hpf and lpf ?

 

[andYz00m]

Not yet, as when I was testing all the basic functions, I notified the HPF makes that crazy noise when hitting the toggle. The other unit, also not calibrated yet does not make this noise

 

[Kevin]

Not yet, as when I was testing all the basic functions, I notified the HPF makes that crazy noise when hitting the toggle. The other unit, also not calibrated yet does not make this noise

Please go ahead and calibrate first. The trimmers can do a lot of things. check sallen key filter to learn about these filters. They can also boost, that's why you probably hear the boost/ bump

 

[andYz00m]

Ok, I’ll try that. It sounds like something is shorted to me but I will check the calibration first.

 

[andYz00m]

Please go ahead and calibrate first. The trimmers can do a lot of things. check sallen key filter to learn about these filters. They can also boost, that's why you probably hear the boost/ bump

You were right. Calibrated fine using REW. Had to turn my output off completely until I got the trimmer under control for the HPF. The cutoff was the problem child.

They both look identical when checked with some sweeps.

Great sounding kit and thanks for the quick support!

I think ill go for the Neumann EQ next.

 

[sadmonkeysound]

I'm about halfway through building a pair of black EQs, and I have a small piece of feedback if there's ever a REV C of these boards... Would it be possible to renumber the component identifiers on the boards so that they're easier to find from the BOM? I'm sure there's a system that makes sense from a design standpoint, but it's caused a lot of slowdown as I have to go hunting for resistor locations.

Alternatively, maybe something like this interactive build map? This was a great help when building my 1176s, both for finding placement locations and keeping track of progress...
https://library.hairballaudio.com/maps/revarack20/

 

[JMan]

I'm about halfway through building a pair of black EQs, and I have a small piece of feedback if there's ever a REV C of these boards... Would it be possible to renumber the component identifiers on the boards so that they're easier to find from the BOM? I'm sure there's a system that makes sense from a design standpoint, but it's caused a lot of slowdown as I have to go hunting for resistor locations.

Is it that you are hoping for the board to be laid out so that, for example, resistors follow a numeric order from left top to bottom right, or something similar to that? (That's a guess, but it's what I'm inferring from what you wrote; apologies if I've misunderstood). If so, that is very unlikely to happen, because the those numbers are referenced to the schematic. In other words, just because two numerically sequential components might appear next to each other on a schematic doesn't mean that they will be situated adjacent to one another on a circuit board, as there are numerous other complex factor at play in a pcb layout. The good thing is that the "slowdown" you experience as a result of hunting for component footprints gives you an opportunity to get familiar with the layout and develop a stronger understanding of where the various circuit blocks sit on the board.

 

[sadmonkeysound]

Is it that you are hoping for the board to be laid out so that, for example, resistors follow a numeric order from left top to bottom right, or something similar to that? (That's a guess, but it's what I'm inferring from what you wrote; apologies if I've misunderstood). If so, that is very unlikely to happen, because the those numbers are referenced to the schematic. In other words, just because two numerically sequential components might appear next to each other on a schematic doesn't mean that they will be situated adjacent to one another on a circuit board, as there are numerous other complex factor at play in a pcb layout. The good thing is that the "slowdown" you experience as a result of hunting for component footprints gives you an opportunity to get familiar with the layout and develop a stronger understanding of where the various circuit blocks sit on the board.

Totally get that, but yes, that's exactly what I'm hoping for. From an assembly standpoint, it's a big part of the reason why the CAPI stuff is so damn nice to build - finding things on the boards is smooth, because they flow the component identifiers spatially where possible. Regardless, I understand what you're saying, which is why a searchable PCB map would also be a great solution. The one in the PDF on the site isn't searchable, and the component locations aren't even sorted within each component on the BOM, all of which makes validating placement slow. That said, having the component values on the PCB is a nice touch, and much appreciated.

 

[Petrosa]

Hey Simon, did you ever figure out what was needed to achieve this? I had the exact same thought for the same reason. If so, or anyone else has, please share. I'm not sure which calculator to use from the link Kevin sent..

Hello,
sorry for the late answer, i missed the notification somehow.
I did not figured out what to do, I was to busy.
But meanwhile there is also a version of the E292, witch has the /3 button for the lmf.
For mixing i prefer one of the other designs, because the low shelf often brings to much low end rumble.
For recording, i like the /3 button, because you can get down to around 100 Hz, where the most recording rooms (also mine) have some resonances.

I ordert 2 units this week, and startet to build yesterday. Im sure they sound killer!

Go and get some

Thanks for this nice pice of work Kevin.

 

[boris1953]

Hello everyone. I built 2 SLQ51X black knobs last week. The builds went real smooth and they both powered up and passed audio with no problem. All controls control their respective bands and seem to sound correct. The problems start during calibration. I can get both units to calibrate just fine on high mid and low mid, but both units will not calibrate the high band and one will not calibrate the low band. Anyone have an idea where I should start my trouble shooting? Thanks in advance. Danny