8 Channel, 3U NEVE 1073 completed

[Whoops]

In order to understand your design I needed to see a schematic.

Which part?Been looking at mu metal cans but the´re like €100 a pop. Stainless steel, if thick enough, will help. I´ve seen that 6mm ferritic steel will work.

But I guess I can just build a nice floorbox PSU instead!

Why go to all that trouble when you could avoid problems by having an external PSU?

 

[XAXAU]

In order to understand your design I needed to see a schematic.

Sorry I don´t know how to draw schematics.

But the design is fairly simple:

8x inputs via Carnhill VTB9046 10K: 600 > RuffRecords passive summing PCB > 4PDT toggle

2x mic inputs > JLM GoBetween with DI > 4PDT toggle

The 4PDT switch toggles between the balanced summing network and the mic/DI inputs

4PDT > Carnhill VTB9045 > EZ1290 > Carnhill VTB9049 > out

I also would like to add VU metering and I have a JLM VU2 meter buffer which I´d like to toggle with a 4PDT between input & output. Don´t know where to tap the signal though. I´m guessing at the input and output trafos of the EZ1290?

And depending  on what AD/DA I get I may need to split the output signal in two: record back to DAW / monitor controller with a stepped attenuator.

Why go to all that trouble when you could avoid problems by having an external PSU?

Yeah I decided to do an external PSU instead! 

Thanks!

 

[Whoops]

And depending  on what AD/DA I get I may need to split the output signal in two: record back to DAW / monitor controller with a stepped attenuator.

if you don't monitor from the DAW's output  how do you know what is reaching the DAW?

I only and always monitor from the DAWs output, thats common practice also for the obvious reasons

 

[XAXAU]

if you don't monitor from the DAW's output  how do you know what is reaching the DAW?

I only and always monitor from the DAWs output, thats common practice also for the obvious reasons

That's true, however the only thing I'm missing out on is the AD conversion. But I might wanna go through some gear on the way in of course. Or clip the converters if it sounds good.

The inspiration for this summing "mixer" / dual mic pre is the Shadow Hills Equinox and it's got a selector that monitors DAW, post summing, mic pres and an extra external source.

Maybe that would be a good idea to implement? However the whole monitor section adds a few bucks to the pile. Rotary selector, cables, jacks, Elma stereo attenuator etc.

I'm leaning towards getting a UA Apollo 8 and it's got a dedicated monitor out so I might skip the monitor section.

 

[Whoops]

The inspiration for this summing "mixer" / dual mic pre is the Shadow Hills Equinox and it's got a selector that monitors DAW, post summing, mic pres and an extra external source.

Maybe that would be a good idea to implement? However the whole monitor section adds a few bucks to the pile. Rotary selector, cables, jacks, Elma stereo attenuator etc.

I'm leaning towards getting a UA Apollo 8 and it's got a dedicated monitor out so I might skip the monitor section.

Well I never had the need to have a selected monitor section in a summing mixer,  although everyone one has different needs.

The Equinox is over the top and has that, but the question is, Do you need it?

Compared how hard do you need that and the extra cost of parts and labour, see if it's worth.

The Apollo is nice for sure.

Anyway this is a thread for the 1290 project and theres a lot of different threads already for summing mixers lets not get too carried way outside the topic.

 

[XAXAU]

Anyway this is a thread for the 1290 project and theres a lot of different threads already for summing mixers lets not get too carried way outside the topic.

Agreed. Thanks for the input though! 

 

[XAXAU]

I´ve got a silly question for you guys. As I´m gonna use the EZ1290 for summing amplification and dual mic pre in the same box I was wondering about the different stages of the circuit and how they sound.

As far as I understand there are two preamp stages (BA183NV) and one line amp (BA183AM). My idea was that when using the box for summing it might be nice to only use the BA183AM for amplication but as I haven´t heard these circuits I wouldn´t know.

I have no idea if this is gonna work but what if you cut off the legs on the middle wafer so the switch now only controls the 2x BA183NV´s and wire in another single pole Grayhill to the middle position?

Thanks!!!

 

[joakimkarlthomas]

Hi! Would using a standard mic cable instead of canare L-2B2AT be ok?

 

[joakimkarlthomas]

Hi again!
The Grayhill switch has three rows of pins to connect to the pcb. Two of them have solder pads on the pcb for all the pins in these two rows. Am I supposed to solder all the pads in each row so the the pads is all connected to each other?

 

[Whoops]

Hi! Would using a standard mic cable instead of canare L-2B2AT be ok?

Hi,
I don't know what the Canare L-2B2AT is, but you can use any mic cable you like.
Thinner is easier than stardard size for the inside wiring, but both will work.

Theres  thinner mic cables from any of the major brands, Klotz, Cannare, Gotham, Vandamme, Belton.
You can also use multicore cables, and strip the multicore to individual cables.
You can by 1 meter of a 24 multicore, and strip it to 24 individual 1 meter cables that will work great for inside wiring on the units.

 

[joakimkarlthomas]

Hi,
I don't know what the Canare L-2B2AT is, but you can use any mic cable you like.
Thinner is easier than stardard size for the inside wiring, but both will work.

Theres  thinner mic cables from any of the major brands, Klotz, Cannare, Gotham, Vandamme, Belton.
You can also use multicore cables, and strip the multicore to individual cables.
You can by 1 meter of a 24 multicore, and strip it to 24 individual 1 meter cables that will work great for inside wiring on the units.

Thanks, was wondering as the guide in particular tells to use canare and not some whatever mic cable. Perhaps the canare is just recommended due to quality. Thanks again!

Link to the guide: https://s3.amazonaws.com/EZ1290/assembly6.pdf

 

[Whoops]

Thanks, was wondering as the guide in particular tells to use canare and not some whatever mic cable. Perhaps the canare is just recommended due to quality. Thanks again!

Link to the guide: https://s3.amazonaws.com/EZ1290/assembly6.pdf

It's recommended that brand to help newbies not using cheap mic cable.
Any of this brands has the high quality needed:
Klotz, Cannare, Gotham, Van damme, Belton, Mogami

 

[Whoops]

Hi again!
The Grayhill switch has three rows of pins to connect to the pcb. Two of them have solder pads on the pcb for all the pins in these two rows. Am I supposed to solder all the pads in each row so the the pads is all connected to each other?

Sorry, I don't understand your question.

Can you refrain the questions? maybe post some pictures so we know what you doubt is.

You put the switch through the pcb holes and then solder each pin to it's own pad

 

[joakimkarlthomas]

Sorry, I don't understand your question.

Can you refrain the questions? maybe post some pictures so we know what you doubt is.

You put the switch through the pcb holes and then solder each pin to it's own pad

Haha, yes sorry for my bad formulation of that question. Well, the pad are so small and close to each other that it might be hard to solder without connections between pads will occur. the guide says something about solder bridges and then I thought I was meant to make bridges between all the pads in each row.

Hard to explain what I mean but I hope i make sense now. Ive also attached a photo with a pen pointing to what I mean with a row of pads.

 

[Whoops]

You have to solder each pin to each individual solder pad, you can't have bridges.

The guide says:

"Use    some    fine    .015”    solder    and    a    sharp    soldering    /p.    The    switch   
solder    pins    are    only    .075”    apart    and    it’s    easy    to    get    a    solder    bridge   
between    them.        "

It means use  thin solder and use a thin soldering iron because as the pins are so close to each other it's easy to  make bridges that you dont want between them.

You sould be using a 11w/12w thin soldering iron for that,
buy one of these:

http://www.jbctools.com/2192040-14st-soldering-iron-product-457-category-8-menu-1.html

https://www.banzaimusic.com/Antex-AT-M240-12W-Soldering-Iron.html

 

[joakimkarlthomas]

You have to solder each pin to each individual solder pad, you can't have bridges.

The guide says:

"Use    some    fine    .015”    solder    and    a    sharp    soldering    /p.    The    switch   
solder    pins    are    only    .075”    apart    and    it’s    easy    to    get    a    solder    bridge   
between    them.        "

It means use  thin solder and use a thin soldering iron because as the pins are so close to each other it's easy to  make bridges that you dont want between them.

You sould be using a 11w/12w thin soldering iron for that,
buy one of these:

http://www.jbctools.com/2192040-14st-soldering-iron-product-457-category-8-menu-1.html

https://www.banzaimusic.com/Antex-AT-M240-12W-Soldering-Iron.html

Thanks, that cleared things out for me. "It's easy" sounded like a positive thing  when I read it, instead of like "it's a big risk" or something like that. So I just wanted to make sure I don't make any mistakes. Thanks a lot!

 

[Whoops]

yes, I got that, no worries.

What soldering iron are you using?

 

[Potato Cakes]

Hi, everybody!

I'm build a single channel of these that I intend to pair with a 2065 HPF/LPF section and on opto compressor. I'm trying to use as many of the parts I already have since I have a pile of various components that has been growing over the last couple of years. For the main board, would there be any significant issues created if 3300uF was used in place of the 2200uF/35V caps and 220uF used in place of both of the 150uF's. It's not a problem of ordering them as I need to get some other parts, I'm just trying use as much of the inventory I have and turn them into fun projects.

Thanks!

Paul

 

[Whoops]

Hi, everybody!

I'm build a single channel of these that I intend to pair with a 2065 HPF/LPF section and on opto compressor. I'm trying to use as many of the parts I already have since I have a pile of various components that has been growing over the last couple of years. For the main board, would there be any significant issues created if 3300uF was used in place of the 2200uF/35V caps and 220uF used in place of both of the 150uF's. It's not a problem of ordering them as I need to get some other parts, I'm just trying use as much of the inventory I have and turn them into fun projects.

Thanks!

Paul

"220uF used in place of both of the 150uF's"

It's Fine.


"3300uF was used in place of the 2200uF/35V"

Yes, more filtering, it will be fine.

Geoff Tanner actually recommends using in that place 4700uf. The value used by Neve because of physical space restrictions inside the modules at the time was 470uf or 640uf, but using an higher value you will have better filtering.

Geoff Tanner

"you will find that capacitors have shrunk in size considerably from back when these modules were new and I would fit something closer to 4,700uF to the connection that goes to pin M."

"When it comes to recap time, large value electrolytics have shrunk in the last 40 years and the capacitors in the frame of the module (usually 640uF) can be replaced with far larger capacitors of the same physical case size now. There should be no problem fitting a 4,700uF 35v in the same location and this will better filter the power supply rail noise from the feedback path in the output stage of the B183/283 and improve the noise marginally."

 

[Potato Cakes]

Whoops,

Thanks for info!

I suspected they would be fine, but I'm not knowledgeable to enough with this circuit to figure out if it would.

Thanks!

Paul