More Green Pre Questions

Hello All,

I have sourced nearly all the parts I need to finish my v14 green pres! I do have a few questions however.

Can I have both XLR and 1/4" outputs on this? I Need to connect the pres to the 1/4" balanced inputs on my Tascam FW1884. If this is possible, would it be a good idea to use something like this? http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=092-042

Also, I am having a hard time locating the SPST and DPDT toggle switches, 10k pot, 1k vr5 multiturn, 10k vr5 multiturn, 4 pin, 3 pin, 2 pin molex connectors and a D70 3-4 amp Bridge Rectifier. Does anyone have any part numbers for any of these for US based vendors?

Thanks a ton!,
KFG

[quote author="kungfugeek"]would it be a good idea to use something like this? http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=092-042[/quote]

That's a female (input) XLR jack. You'd still need a male XLR for the output, which defeats the purpose of using the combo jack in the first place.

Or you could make yourself some special male-to-male XLR cables, I guess...

Peace,
Al.

Doh, right, well can I add regular 1/4" jacks then? If so, do I just wire them up in paralell? What would I need to do to add instument inputs? Basicly I'd like to have balanced 1/4" outs as well as 1/4" instrument inputs, so I could plug a bass, etc directly in.

[quote author="kungfugeek"]can I add regular 1/4" jacks then?[/quote]

Yup!

[quote author="kungfugeek"]do I just wire them up in paralell?[/quote]

Yup! (observing proper signal polarity, of course).

[quote author="kungfugeek"]What would I need to do to add instument inputs? [...] so I could plug a bass, etc directly in.[/quote]

A pad, maybe?

Peace,
Al.

Hey KFG

I have the Newark part numbers at home, I'll post them when I get home from work tonite.

Cheers

[quote author="alk509"][quote author="kungfugeek"]can I add regular 1/4" jacks then?[/quote]
Yup!
[quote author="kungfugeek"]do I just wire them up in paralell?[/quote]
Yup! (observing proper signal polarity, of course).
[/quote]
While on the subject of (multiple) 1/4" outputs on the Green Pre... What would happen if i plugged into both outputs at the same time, i.e. one for recording and one for monitoring? Not knowing anything about electronics, I would assume that the output only gets roughly half the normal impedance, but would it matter?

/martin.

[quote author="kungfugeek"]
A pad, maybe?

Peace,
Al.[/quote]
And, while on thye subject of pads, is it stupid not to build the Green Pre version with a pad? How hot i the lowest gain setting? Will a sensitive condenser and a loud source clip the Green Pre at the lowest gain setting?

/martin.

Thanks guys!

So what is the best way to impliment a pad?

[quote author="kungfugeek"]
Also, I am having a hard time locating the SPST and DPDT toggle switches, 10k pot, 1k vr5 multiturn, 10k vr5 multiturn, 4 pin, 3 pin, 2 pin molex connectors and a D70 3-4 amp Bridge Rectifier. Does anyone have any part numbers for any of these for US based vendors?

Thanks a ton!,
KFG[/quote]

Mouser part #s:

10TF130 - SPST toggle, for vertical PCB mounting!
10TF160 - DPDT toggle, for vertical PCB mounting ! (currently back-ordered)
313-1220-10K - 10k audio pot
594-64W102 - 1K multiturn
594-64W203 - 20K multiturn (you said 10K, no 10K on this BOM-V14)
538-50-57-9404 - Molex 4 pin connector
538-50-57-9403 - Molex 3 pin connector
538-50-57-9402 - Molex 2 pin connector
538-70543-0003 - Molex 4 pin header
538-70543-0002 - Molex 3 pin header
538-70543-0001 - Molex 2 pin header
538-16-02-0103 - Molex pins

can't help with the brige rectifier at this point, sorry

Oh yeah, and on the subject of pad, I always like having one there, even if I never use it, cause someday I WILL need it. One extra switch is worth the expense in my mind

Good luck!
Andrew

Awsome thanks, happen to have the Mouser number for the 100k multiturn as well?

All I need now is an enclosure and some elusive resistors!

594-64W104 for the 100K, this is the same vertical footprint as the others. Although the BOM suggests a flat pot, the drilling on the PCB allows for both.

Elusive resistors?? Mouser had everything I needed, although, as always, a couple strange resistor values had to be close, not exact.

Andrew

Hmm, I am haivng a hard time finding several of them. How far off can they be?

Thanks again!
KFG

what values can't you find?

For Green PS
2k2 AXIAL0.4 Resistor 1% 1/4w
8k2 AXIAL0.4 Resistor 1% 1/4w

For Green Pre
Just about all of the 1/4w 1%
For must I could only find .1% and they seemed expensive. Also some were off such as 220k vs 221k, I have no idea how much these values can be off with out noticably affecting the audio. Most of my problem is that im a newbie and don't know all the ways I can search for parts what different ways to say the same thing, etc. (if that makes sense lol!)

OddHarmonic, do you still have your complete list from Mouser? Or are you just looking these up on the fly?

Thanks!,
KFG

resistors are very very very easy on mouser. Xicon 1% metal film 1/4W are 271-value.

So for your 2k2, it's 271-2.2k

for the 8k2 it's 271-8.2k

you can find pretty much any resistor value you need that way

273- gets you 1/2W 1% metal films,
291- gets you 1/4W 5% carbon films, which you'll need for the couple of tiny tiny values in the gain switch, like 1.5 ohms (291-1.5)

Super simple, eh?

Mouser's catalog browser takes some getting used to, but once you're used to it, you can find so much useful stuff

Wow, awsome, thanks! I'll spend some time trying to round up the last of my parts tonight.

You guys rock,
kfg

btw, those KK headers and housings can be had for much much much less than that, some of the KK parts are very very expensive, I can't see paying a dollar for a 2 pin header.

Try these part numbers:
538-22-01-2041 4 CKT TERM HOUSING $ 0.300
538-22-01-2021 2 CKT TERM HOUSING $ 0.140
538-22-01-2031 3 CKT TERM HOUSING $ 0.220
538-22-03-2031 VERT PCB HDR 3P TIN PLATING $ 0.180
538-22-03-2041 VERT PCB HDR 4P TIN PLATING $ 0.240
538-22-03-2021 VERT PCB HDR 2P TIN PLATING $ 0.120

those prices are much saner for me

Alright was able to find all but three final parts.

Green Pre
100nF, Radial, / polycarb / polypropylene / polystyrene / polyester
22pF, Radial,Good Quality(Wima), Polycarb / polypropylene / polystyrene / polyester

Green Pre Power Supply
3 or 4 Amp Bridge Rectifier, D70 Package (Square with 4 pins, PCB mount)

Thanks again all!
kfg

You're right, Molex connectors come in all sorts of shapes and sizes, some cheap, some expensive. Anything with a .1" spacing will work here. I picked the SL series because I like the headers to have a casing around the pins, and the gold adds to the cost as well. Perhaps I'll try the cheaper series next time around.

andrew

> Can I have both XLR and 1/4" outputs on this?

Yes.

> What would I need to do to add instument inputs?

A DI box. Pads on mike-inputs still give too low an impedance for guitar pickups. Mikes can push long cables, pickups can't. So put a DI box, transformer or active, near the instrument and run a mike-cable to the mike-input.

> I would assume that the output only gets roughly half the normal impedance, but would it matter?

It doesn't "get an impedance". And unless you have somehow found two 600Ω inputs (nearly all modern inputs are 10K) it will be perfectly happy with two, three, even four loads.

A drawback is that when someone stomps on the monitor cable and shorts it, the recorder's signal also goes away. In my live concert work, everything is properly splittered so any number of shorted outputs will not kill signal to any unshorted outputs. Show must go on (tape).

1% resistors are often specified with odd numbers, like 2K21 instead of 2K2, to make it harder for some dumb worker to use a 10% resistor. In this amp, no single value is critical to 10%, but there are several pairs that should match pretty close. The two 6K8 resistors in the phantom: they could be 6K2 or maybe 7K2, but both should be the same within 1%. Since the amp is push-pull, there are places where you find two 2K2 or 4K7 or something resistors with similar connections to two opamps: these should be matched even if somewhat off from the number on the plan.

Though frankly, I think the Green would mostly work just fine with 5% resistors and nominal values +/-10% from the numbers on the plan. Even the Phantom: with 95% of mikes in most situations, you don't need 1% matching.