## eurorack widths of panels?

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intellijel
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### eurorack widths of panels?

I looked at this document:http://www.google.ca/url?sa=t&source=we ... k7rnBE1v_A

but the written definition of hp conflicts with the diagram.

It says that euro modules are in multiples of HP (5.08")

so that

1HP = 5.08mm
2HP = 10.16mm
4HP = 20.32mm etc. etc.

However in the diagram it shows a dimensioned center of a panel to be a single HP section and implies that multiple HPs would multiply this section. However the section has 7.5mm on either side of it (15mm) which is not a division of a single HP.

So by that diagram a single 1HP panel would be 15mm+5.08mm = 20.08mm which is close to 3HP but not exact (4HP = 20.32). Is this to make the panel slightly smaller for spacing (as mentioned in their notes).

I just want to know if I am designing panels, what multiple of size I am using and then where the default mounting holes go.

e.g.
1HP = 7.5mm -hole - 5.08mm - hole - 7.5mm = 20.08mm
2HP = 7.5mm - hole - 10.16mm - hole - 7.5mm = 25.16mm

NV
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Your link doesn't seem to point to where you intended, which I am assuming is the following document: http://www.elby-designs.com/panther/euro-frac.pdf

Your confusion stems from the mounting holes. The photo you are referring to is a diagram which illustrates how the mounting holes alone are oriented on a module. It is not meant to suggest how to calculate the precise HP width of a module. The reason for the seemingly random 7.5mm value is so that the module can mount alongside other modules without consuming an additional mounting hole. 7.5mm is an HP and a half - if the 7.5mm number were an HP unit instead (5.08mm) then the edge of the faceplate would end up obscuring half of a mounting hole rather than ending up in between mounting holes as the faceplate should.

This page has a precise diagram, including the original photo from the document you're discussing: http://www.doepfer.de/a100_man/a100m_e.htm

Note the differences between calculated panel width and actual panel width. A panel that is precisely 40.64mm (technically 8 HP) in width will not fit in a subrack alongside other modules. Instead it needs to be slightly smaller (40.30mm or less in this case). The mounting holes should be placed 7.5mm in from the edge of the calculated faceplate in order to properly line up with the rails for a euro subrack, regardless of what the actual width ends up being; be sure to take this into consideration. Also note that it is always better for a faceplate to be slightly too small than slightly too large - there's very little room for error in a packed euro rack and a module that is slightly too small will still fit, whereas too large will not.

intellijel
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thanks for taking the time to write that detailed reply! That definitely clears things up.

consumed
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i dont know if you are using FPE/schaeffer for your panels, but i would really recommend that you

1. use the 'actual' dimensions that doepfer lays out for panel sizes,
2. use mirrored d-holes mounting holes for best fit (just like cwejman)

fonik's fpe designs use the d-holes and they work out perfectly and are far superior to round holes. i use them for all my panels now.

Luka
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i might make this a sticky, this is useful diy information

im interested in dimensions for density of pots and jacks
does anyone have any guidlines / rules of thumb

Randaleem
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### Density vs. Usability It's about more than dimensions!

Luka wrote:im interested in dimensions for density of pots and jacks
does anyone have any guidlines / rules of thumb
Hi Luka, Great question!

A lot depends upon the knobs and patchcords you use. For the ubiquitous Rean softouch 16mm skirt knobs Blacet and others use, the Doepfer dimensions work out okay. Blacet pots are tighter vertically, but there is plenty of room on either side of them to make up for the vertical closeness. Keep in mind that some commonly used patchcord connectors have a larger diameter than others. I've seen modules which won't allow a very commonly used patchcord to fit; the jacks are just too close together!

FWIW, Doepfer and Analogue Solutions use 20mm vertical spacing for pots. The imperial .800" is often used as the equivalent of 20mm spacing.

Serge uses 3/4" (19mm) vertical spacing on many of the new modules. This works because they use the Davies 1900-H knob which is only 1/2" diameter. (The Rean softouch is about this at its top too. So you could conceivably get away with this vertical spacing for them too. But Serge uses 1" horizontally, and this 3/4 by 1" grid is worst case for all modules. Euro designs push things quite a bit closer. To the detriment of use in many cases, I think.

Usually it's a good idea to increase the horizontal pot spacing if/when you push the vertical spacing. Or vice versa. It's also important to keep the pots and jacks far enough away from the edge of the panel! So that ANY modules on the sides of the one, don't prevent it or them from being easily used! It seems many designers forget this point?

I try to have pots at least .400 from the panel edge, and jacks too. But sometimes jacks end up at .350, and Doepfer and others put them even closer.

A couple days ago I did a gatebus add-on for my soon-to-be-released touch sequencer, and it looks like I may need to change the touch seqencer panel. The gatebus module has the tightest density I've ever done, with 18 switches, 5 jacks and 6 LEDs(I wish I could put in 22 LED's, but there's no way!) in 7HP (1.5" in Frac). It looks and works fine on its own. But two of the TouchSeq panel knobs (glide and touch keyboard output scaling) get in the way of the horizontally actuated bus select switch bats when the GB is at its expected place to the right of the main Seq panel. I don't want to change the gatebus module, because it needs to be narrow to keep the whole sequencer setup within one 19" row. But something needs to give! Keeping in mind what I wrote above, the kaybd scale knob probably won't be changed during a patch, but the glide knob certainly might!

For jacks, I like to have .650" between and at least .550 vertically. Many recent modules really push the jacks close together in the name of functional density. But functional useability needs be equally addressed IMO.
The closeness guidelines can be balanced against the expected usage of a given panel element. For example, you can expect that the v/oct input to a VCO will likely be filled, but won't probably be repeatedly removed and inserted during a given patch. So you can perhaps put it closer to a second input or pot/switch which will also likely be used but not often changed. IOW they can be closer together because you don't expect them to be "performance" operators. They are set up once, and left that way. Inputs and outputs of a matrix mixer are another example where tighter than usual spacing may be acceptable. But here is also an example of pots which need to be further apart! Because you DO expect that these WILL be performance controls.

Switches need enough room to actuate them, and consideration of their actuation direction too! Again being mindful of whether it is a performance or setup operator...

The biggest issue IMO is how you arrange things around the knobs, and in relation to each other! There is a just-posted thread here showing how an inserted jack of a commercially offered module obstructs flipping a switch downwards, because the jack is in the way. I'm seeing more and more of this in recent modules as designers try to give customers the most in the least space. But I've also noticed lately that the backlash has begun. Thank God! People are *finally* noticing that space is not an enemy, even if it means your case needs to be larger!

I always try to imagine an opposing thumb and finger of a large hand trying to turn pots or flip switches with ALL jacks filled, and "worst case" modules left and right of the one I'm designing. This means that if I have to put something at the side of the pot, I'll be sure to leave more room at its top and bottom to make up for it.

Most of my modules end up using a "checkerboard" layout where jacks switches and knobs are only located on the black OR red square locations.

I always print up a layout and fasten it to a piece of cardboard and fit parts to it to actually test the thing in the real world. IMO that's the only way to REALLY find out when functional density is beating up functional use!

FWIW, I have an extensive database of synth Mfrs. layout dimensions, past and present. I'm planning to put it up on my website, sometime this Summer.

Kind regards, Randal

Kind regards, Randal

Luka
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the cardboard method is great
i usually use that but unfortunately my laser printer needs a new toner cart.

ive made a few frac modules but i just copied other poeple designs
now that im entering into euro territory im keen to know how dense you can do without going overboard.

here is my first euro design for topp's buchla 281 boards

i used diameter 30mm for pots and 20mm for jacks (well im using bananas)
this design actually exceeds these minimum limits
and panel is now 21HP for a dual envleope module

do you think im wasting space?
should i tighten up the component density?
im all for dense due to the limited capability of modules i can fit into my suitcase so is it worth making it super tight?

DGTom
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Maybe have a look at keeping the switches nearer the jacks for 3U,

the great thing about Davies + Banana combo is there is a load of finger room you don't have with the reans or doepfer knobs. I decided to experiment & swap my Blacets over to Davies clones... & it aint goin' back! Monochromatic FTW!

Now I just gotta convert em to banana

That layout looks pretty good, I gotta do cardboards to know for sure tho & I need to find some smaller switches, futurlecs minatures are as big as my 9mm pots behind the panel!

I'm using a mixture of Serge & Blacet grids which is working pretty well for density in 3U.

Luka
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here is the 18HP version

is this too dense?

Randaleem
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### In euro, more than a handful is wasted!

Luka wrote:here is the 18HP version is this too dense?
Hi Luka,

If you're selling these, IMO the second one will sell far more units than the first in the current Euro marketplace. But that is not the same question as "is it too dense?"

I keep saying that how you USE a module changes depending on all its physical factors. Size/ distance is only part of it. If you've chosen Euro, you've already constrained yourself into several physical and mental realities.

Going to a module knob like you're about to pinch a nipple uses a completely different part of your brain, nerves, and muscles than grabbing the whole mammary! Each might feel good, but you will both give and receive a different response. Grabbin' tits is different from pinchin' nipples!

It'll be hard to convince me that somehow these physiological/psychological differences do not appear in the sound which results.

The reason so many formats exist is the result of the truth of this statement, IMO. Size matters. But It's not all about size!

Kind regards, Randal

Randaleem
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### Details matter.

Hi again Luka,

Specific to your posted pics, I like the second one better. But that's because I've spent the last couple years designing dense Euro/frac module layouts. Before this, I'd have chosen the first one.

In any case, on this second one, I'd change the angle of the line connecting the A,D to its respective CV knobs. Use the 3rd line of the A,D instead of the bottom. That way the line will appear to go through the middle of the knobs and be more traditionally/visually pleasing.

Having said that, the way it is now WILL affect its use. So maybe you're not looking for visually pleasing? (YMMV. But I'd change it, were it mine.)

Kind regards, Randal

Luka
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im not selling

i actually am doing the painful but rewarding project of building my modular from the ground up. I originally designed it all in 5U but i found that i cant etch panels that size due to size limitations of pnp blue transfers so im moving to a new smaller compact size.

i have already etched a few frac modules but am considering re-panneling them as frac seems like a dead format and it would be nice if down the track if i wanted to intergrate some professional modules i could select a well established full market.

the thing im finding hard with euro is it is so hard to pick a width. there are so many to choose from. it is really quite annoying to be honest. with 5U and frac you could roughly judge how wide your module would be due to the Unit size being so large. These euro HP units are so small i find you just have to design a layout and see how wide it is then try re-fit it to the closest HP dimension.

then you have to think about functionality vs density
then you have to think about ergonomics
etc

it is a lot trickier than im used to
but neverthless i do like designing panels

i guess i might just see if i can source a printer somewhere and try it out on cardboard. see how i go.

thanks

Randaleem
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Luka wrote:i have already etched a few frac modules but am considering re-panneling them as frac seems like a dead format
I think if you use Banana's in your Frac, you'll find in the future that you will have the options you hope for... IOW, I believe the future of Frac is bananafied Frac. And I am working in support of its future success. See next part of the reply.
and it would be nice if down the track if i wanted to intergrate some professional modules i could select a well established full market.
Well Frac IS already well-established. And the universal rail, PSU's and cases I'm making will make it FAR easier to integrate FRAC and Euro than it has been in the past. And should you later change your mind in support of one or the other, you won't be having to lose a bunch of money. Just flip the rails, reset the PSU's, and continue. Same cases. Same power. Same rails. And NOT "rack-width" limited.
the thing im finding hard with euro is it is so hard to pick a width. there are so many to choose from. it is really quite annoying to be honest.
TOTAL agreement! While it is exactly this which has created the niche for my cases and related bits to fill, it is easily the single greatest contributor to the high cost of Euro cases!
with 5U and frac you could roughly judge how wide your module would be due to the Unit size being so large.
Since I'm working in support of BOTH frac and Euro, Here's what I do. It may help you? I always do the Frac panel first. Anything which fits Frac will fit Euro, with the exception of lettering in the approx. 2mm strip you lose at top and bottom of the frac panel going to Euro. I'm now trying to make all my designs work with a single silkscreen for both the frac and euro module, so the lettering at top and bottom is a bit higher on the Frac panels than i'd otherwise want.
Anyways, you get the benefit you described of immediately knowing the rough size to fit things to. And if sometimes yo find that the large Frac increment is TOO large for a certain Euro module, it is easy enough to shrink the panel around your Frac work to fit! Works for me, hope it helps!
then you have to think about functionality vs density then you have to think about ergonomics etc it is a lot trickier than im used to
Yes.
but neverthless i do like designing panels
And you're good at it!

Kind regards, Randal

Luka
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well i just traced the 18HP onto paper, then placed onto cardboard and it is far too tight to even get the pots in
time for a re-draft

neandrewthal
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DGTom wrote: the great thing about Davies + Banana combo is there is a load of finger room you don't have with the reans
I find it's the opposite The reans feel more roomy to me since you don't have to grab them so hard. I'm sure the Davies are fine on Blacets, where you have unrestricted access to to sides of each knobs, but for my panels(some looking more like Luka's 18hp function generator) they're a no-no.
Initiate the sequence, create catastrophe.

consumed
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### Re: Density vs. Usability It's about more than dimensions!

Randaleem wrote:A lot depends upon the knobs and patchcords you use.

FWIW, Doepfer and Analogue Solutions use 20mm vertical spacing for pots. The imperial .800" is often used as the equivalent of 20mm spacing.

Serge uses 3/4" (19mm) vertical spacing on many of the new modules. This works because they use the Davies 1900-H knob which is only 1/2" diameter.

Usually it's a good idea to increase the horizontal pot spacing if/when you push the vertical spacing. Or vice versa. It's also important to keep the pots and jacks far enough away from the edge of the panel! So that ANY modules on the sides of the one, don't prevent it or them from being easily used!
...

Switches need enough room to actuate them, and consideration of their actuation direction too!

I always print up a layout and fasten it to a piece of cardboard and fit parts to it to actually test the thing in the real world. IMO that's the only way to REALLY find out when functional density is beating up functional use!

heavily edited to get to the juicy bits
see randal's post above for articulation