Calrec PQ 1061

[soundguy]

If we are going to go with a satellite board, it might make the most sense for everyone if we agree to do a standard footprint so people can chose from the many available opamps out there. If the EQ winds up on the front panel board, there will be plenty of room on the motherboard PCB to not need to do a small opamp like that (which is why I suggested just laying out the opamps on the motherboard, there would be plenty of room and cheaper to manufacture).

dave

 

[JustinS]

I second having the opamps on the main board... and having 2 layouts, 1 w' pre & lp / hp filter only - maybe just a hp filter only, perhaps set at 50 & 80?? And a layout with full EQ. Also what are the specs of the original Sowter tranny?? i.e. voltage step up etc.

Justin.

 

[MikoKensington]

My interest is high but my knowledge low. The idea of preamp and hp on it's own board sounds nice. As jumping into a whole pre/EQ could get pricey.

 

[soundguy]

I think my excitement over this one is getting a workable project going that everyone here can afford. When you consider the additional cost of the EQ, the main expense is going to be the inductors. Beyond that its bunches of little parts that sure, will add up, but if we lay it out for plastic lorlins, dont have satellite opamp boards, etc. I think the price of adding the eq circuit to the pre could be quite managable for everyone.

Perhaps this is just a good excuse to try to get a lab collective project happening for a discrete transistor EQ design. This EQ IMO serves as a geat point of inspiration as it woudnt be too hard to make, the EQ sounds fantastic and is flexable as you'd want and if we are smart, can be made more affordably for the folks who are daunted by the price of the 1081 project (as well as its complexity).

I wish I was able to actually lay out boards and think, unfortunately my skill pretty much ends with getting people excited and soldering parts.

dave

 

[rafafredd]

I think we should go with the original layout like tommytones did with the N#E#V#E 1081.

You would just need to scan the boards and draw over it.

I like cheap, and one can always save money by winding his own inductor and using low cost switches, so, no need to mess with the layout.

 

[ddt]

If someone can do a scan I can have a go at a pdf...

Dan

 

[JustinS]

Why keep it the same layout?? You'll need to use expensive switches, make a bunch of the little amp boards & purchase appropriate connectors and attach them to the motherboard... why not make a larger motherboard set out with easily obtainable switches, keeping the rough layout for the amp boards but just spreading them out on the motherboard instead of plugins?? Easier & cheaper :grin: Both things that I'm into!!

Justin.

 

[kvintus]

Why keep it the same layout?? You'll need to use expensive switches, make a bunch of the little amp boards & purchase appropriate connectors and attach them to the motherboard... why not make a larger motherboard set out with easily obtainable switches, keeping the rough layout for the amp boards but just spreading them out on the motherboard instead of plugins?? Easier & cheaper Both things that I'm into!!

Justin.

Totally agree. There's no reason to make this project harder to build than necessary. And by the way, I'm interested in building one too.

/Anders

 

[soundguy]

with all due respect, we already have one project with an original layout which is intensely complicated to build and prohibitively expensive for many people. Documentation is also not spot on. Has anyone even finished one of those 1081's yet? tons of us bought parts... The whole point of doing this would be to provide a project with the straight forward writing on the wall and ease of asny of the gyraf projects. By taking the EQ off the motherboard and putting it on a satellite board so you can use lorlin switches means by proxy a total and complete redesign of the thing. Frankly, these EQ's are not so expensive to purchase where it makes any sense to build one that is a total replica of the original thing down to every last detail. I'll just go buy one, there's no way its gonna be cheaper to build like that, winding your own inductors or not. If we could just take the schematic and layout a board set with economy in mind, it will put a discrete transistor EQ project into the hands of pretty much everyone here for not a lot of money. To just do a clone completely and entirely defeats the purpose that Im suggesting, which is saving money and having an EASY project to put together. Also, its kind of a stick up the rear for the reputation of this group.

Unfortunately, I dont know how to lay out a board, I by no means am that sophisticated to do any help on this besides trying to gain the interest of the group and steer the direction of the project with suggestions. If we cant do it with lorlins, there isnt much point in doing it. If we can do it with lorlins then we have to completely redesign the thing in the first place, so its probably appropriate to decide wether or not to a) actually redesign the boards and then b)figure out what is involved in that and see c)who would be interested in putting in all that work. Believe me, if I could do it, I would but I promise this group does not want to be building any PCB that I had a part in laying out. Maybe in 5 years, but Im just the wrong guy for that.

dave

 

[cannikin]

I agree with dave. If we can make this project less difficult, by all means lets make it that. I think those who are advanced DIYers can always modify the basic layout and can take it to a deeper level if they wish.

I too am unable to build a PCB board at this time - just not enough experience yet - but I do promise I will be looking to purchase quite a few boards from the person who manufactures them.

Like I said before the Calrec 1061 is amazing sounding.

Let me know how I can help :grin:

 

[BuzAllen]

Ditto to whats being said. After looking inside the unit more, to make a duplicate would be very challenging. Reproducing the mainboard is one thing but so much of the desgn (eq resistors & caps) are on verticle boards and I dont want to de-solder them to scan them or reverse-e. Additionally the method used to mount the DOA's is great but sourcing these and other 'unique' parts (at least unique to what I've come across) sound like more work than personally I'm into and probably gets pricey.

Dave's point on the cost of these things is valid. The Brent-Averill page for these units showed a price of a bit over a grand (http://www.brentaverill.com/cal_eqp/) , though I don't know if that is current anymore. Thats damn cheap for what you get and there is no way I can see a DIY replica not costing close to that. If the DIY could be 1/2 the cost, then maybe but I don't see that happening. The switches alone (a 24 position + trim down the middle for gain, a 12 with a pot down the middle, 2x6's with the same and then the 2x6 pos switch for the HPF/LPF that are on separate shafts) Throw in an input and output xformer and it's already getting pricey.

The price is why I was looking into only building pres out of it, or I'd just buy the unit itself, but since using the units I've grown to like the EQ's (sorry Gideon) and am curious to see how affordable it could be. I'd actually like to do the PCB's but with my coming work load for the next few months it would be silly for me to say I can do it. I'm still planning on working on it as I sit in hotels for the next few months but someone with more time might be better apt to do it as I can't say I'll get anywhere for a while.

What about breaking up the design? Start with a simpler pre-amp end on a small 2x3" board with switches and pots off board or on a sub board like the SSL project using some of the simplifications that Dave and others talked about. EQ could be on a separate board added or not. That way a pre could be up and running pretty easily then make the eq a separate project. This would not be 'original' but I personally dont care. I just want a box that offers this sound.

Brian

 

[cannikin]

[quote author="BuzAllen"] What about breaking up the design? Start with a simpler pre-amp end on a small 2x3" board with switches and pots off board or on a sub board like the SSL project using some of the simplifications that Dave and others talked about. EQ could be on a separate board added or not. That way a pre could be up and running pretty easily then make the eq a separate project. This would not be 'original' but I personally dont care. I just want a box that offers this sound.

Brian[/quote]

I'm game for this. The main statement "I just want a box that offers this sound"

The 1161 calrec's are going for about 3000.00 for 2 channels.

 

[BuzAllen]

What's the difference between the 1161 and 1061? The one's Ive got here are 1061's but I've come across references to the 1161.

Brian

 

[cannikin]

I don't the differences between the 1061 and 1161.

Here's a picture of 1161 at VKA

http://shopping.netsuite.com/s.nl/c.360669/category.159/it.A/id.960/.f

 

[TomWaterman]

I agree it will be great to make as cheap as possible.

How about putting the preamp and filters on one eurocard board and the main eq on another?

That way you can build whatever part you want, just the preamp or all of it. Only real expensive parts are the 24way gain switch and the iron.
The 2x6 switches shouldn't be that expensive, max $15-20 for grayhills and much lower for lorlins. There are NSF modular switches too.

I don't like the idea of mounting the pots, switches etc to a frontpanel board as that restricts layout and everyone has to choose the same parts etc....

I would go for two main boards with either satellite PCBs for the gain blocks or layed out directly on the mainboards.

I reckon you could squeeze 8 amp blocks onto a eurocard if you were etching at home.

Buz is there any way we could see the back of the gain module? I have almost finished a layout and the parts are in the same places but I wonder about the tracks?

Cheers Tom

 

[gyraf]

[quote author="BuzAllen"]What's the difference between the 1161 and 1061? The one's Ive got here are 1061's but I've come across references to the 1161.Brian[/quote]

It seems that they're the same. The PCB for a known-1061 is marked 1161-13 if you look closely:

Jakob E.

 

[ddt]

Hmm, you guys are right, it's just that making a pdf was something I could do, whereas I've no experience in doing a layout from a schematic. :?

d.

 

[BuzAllen]

Tom, is this what you are looking for?

I also agree with your point on just leaving the switches and pots on their own rather that a PCB for them. More flexibility.

Brian

 

[TomWaterman]

Buz you star!!

Nice one - I was pretty close.

I'll make some tweaks when I get home tonight and try and post it up.

BTW how do they connect to the main board, into slot connectors?

Cheers Tom

 

[BuzAllen]

Tom, here's a picture of the mounting mechanism used for the gain blocks.

Brian