Mike Keith
Well-known member
Yes the phantom comes before the pad,
API 325 to 312...help please.
- Thread starter furmound
- Start date
Help Support GroupDIY Audio Forum:
furmound
Active member
Thanks so much gents!
That schematic is most helpful Dave. Thanks!
I will reorder C6 (again) with the rest of the parts I need for the pad/phantom/phase section.
I can't wait to finish this project so I can start on my SSL comp!
I will certainly be back with more questions regarding padding the output for additional 2520 drive.
That schematic is most helpful Dave. Thanks!
I will reorder C6 (again) with the rest of the parts I need for the pad/phantom/phase section.
I can't wait to finish this project so I can start on my SSL comp!
I will certainly be back with more questions regarding padding the output for additional 2520 drive.
furmound
Active member
Damn switches are expensive! I'm looking for gold plated (as recommended by jensen schematic) DPDT switches for pad and phase for 8 channels. Any recommendations?
digikey has nkk switches that are a few bucks a piece that are pretty high quality for the price. Gold plating is probably good insurance down the line but I dont know how necessary they really are. I would think the general construction of the switch probably outweighs the plating material in a straight comparison. You'll have audio going through those switches and the switches arent typically sealed, so dirt and dust is eventually gonna get in there and thats where you noise is going to come from first, I would guess this to happen wether or not you use gold plating or not.
dave
dave
furmound
Active member
Thanks Dave, I'll check them out today. BTW, do you still have that card cage? I sent you a PM about it and I got a notification for an incoming PM today but there was nothing in my inbox. Was that you by any chance? Is anybody else having trouble with PM's? I don't know if I should be posting this here. Sorry if it's a mistake. Just a little confused.
furmound
Active member
What should the switches be rated at in terms of amps? The choices usually are like 2A, 3A, 6A, and up. I imagine the one for turning phantom on an off is a different rating than the polarity and pad.
furmound
Active member
I'm sorry to repeat this nube question but I wanna make sure that I buy the right switches and I haven't found this info anywhere (maybe my searching skills suck.) I know that I need spst for turning phantom on and off and dpdt for polarity and pad. But there are so many options in terms of amps. I know that the audio switches will not have much running through them but the phantom power switch probably will. I found some nice dpdt switches that are rated 0.3A at 125v. This will be fine for pad and polarity, right? What about for phantom?
Thanks.[/i]
Thanks.[/i]
peter purpose
Well-known member
Thems'll do ya...... now get on with it..!!
furmound
Active member
I tested the cards through a jig and they all sound distorted! All the cards sound the same. Farty, distorted sounds that only pass through at louder volumes. I double checked my steps and will triple check now but I wanted to post this to see if anyone else has experienced this and could offer me guidance in trouble shooting. My edge connector looked like this:
1:V+
2:V-
3:common
4:lo in from pin 4 of 2622 xfrmr
5:hi in from pin 3 of 2622 xfrmr
6:
7
ot
8ot
9:
10:lo out to pin 3 on (M) xlr
11:shield to pin 1 on (M) xlr
12:tied to 11
13:hi out to pin 2 on (M) xlr
14:
15:
What should I do!?!?
1:V+
2:V-
3:common
4:lo in from pin 4 of 2622 xfrmr
5:hi in from pin 3 of 2622 xfrmr
6:
7
ot8
ot9:
10:lo out to pin 3 on (M) xlr
11:shield to pin 1 on (M) xlr
12:tied to 11
13:hi out to pin 2 on (M) xlr
14:
15:
What should I do!?!?
peter purpose
Well-known member
Tie 3 & 4 together as Dave says.
Tie 11 & 12 together. Not going anywhere else.
peter
Tie 11 & 12 together. Not going anywhere else.
peter
furmound
Active member
WOOOOOHOOOOOO!!!!!!!!!
Sweet, undistorted sound is what comes out of my cards after these mods. I can't thank you gentlemen enough.
Only problem now is that when the pot is fully open I get uncontrollable feedback (with or without a mic plugged in.) Actually it starts when the pot is almost fully open and the pitch of the feedback dives down as I continue turning it. I guess this has something to do with the infamous R3. Any suggestions.
THANK YOU!!!
Sweet, undistorted sound is what comes out of my cards after these mods. I can't thank you gentlemen enough.
Only problem now is that when the pot is fully open I get uncontrollable feedback (with or without a mic plugged in.) Actually it starts when the pot is almost fully open and the pitch of the feedback dives down as I continue turning it. I guess this has something to do with the infamous R3. Any suggestions.
THANK YOU!!!
peter purpose
Well-known member
Fur,
What did you end up using for C6 on the 325 schematic?
peter
What did you end up using for C6 on the 325 schematic?
peter
furmound
Active member
i'm so embarrased. i guess i accidentally started a new thread with the reply to your question Peter. i'm laughing at my self right now.
anyway, did i use the wrong cap?
anyway, did i use the wrong cap?
peter purpose
Well-known member
Yeah, that should do you nicely.
I can't think why you'd be getting the feedback though.
Maybe someone who knows what they're talking about will chime in.
peter
I can't think why you'd be getting the feedback though.
Maybe someone who knows what they're talking about will chime in.
peter
furmound
Active member
I wonder if I wired the pot wrong. The third lead of the pot does not need to be terminated like a rheostat, does it? (yes i am a nube)
peter purpose
Well-known member
fur,
Looking at the back of the pot and with the terminals pointing skyward, I join left and centre as one terminal and right as tother.
peter
Looking at the back of the pot and with the terminals pointing skyward, I join left and centre as one terminal and right as tother.
peter
furmound
Active member
I know it's been a while but I wanted to say thanks.
Thanks to everyone who helped me here I've managed to rack up 6 of these. I'm REALLY happy with them. I've recorded a few sessions with them and they kill on drums and guits. On two of the channels I'm using MAP 5004's instead of the 2120's and they're very different. They seem to crap out earlier.
I keep thinking that something is wrong because "I" put these things together. You know what I mean? So i'm going to do a side by side comparison to my friends 3124. I hope I don't realize that they sound like ass and all this time I was just hearing what I wanted to hear.
I still have some work to do though. I did not include phantom power, pad, or phase reverse on these yet. Gotta do that. And I'm not too happy with my grounding scheme either. The noise floor is a little high for my taste when I'm using it at a place that does not have good AC out of the walls. I really like the star grounding on Peter Purpose's stuff. I'm gonna do that next.
Anyway, thank you, thank you, THANK YOU!!!
Thanks to everyone who helped me here I've managed to rack up 6 of these. I'm REALLY happy with them. I've recorded a few sessions with them and they kill on drums and guits. On two of the channels I'm using MAP 5004's instead of the 2120's and they're very different. They seem to crap out earlier.
I keep thinking that something is wrong because "I" put these things together. You know what I mean? So i'm going to do a side by side comparison to my friends 3124. I hope I don't realize that they sound like ass and all this time I was just hearing what I wanted to hear.
I still have some work to do though. I did not include phantom power, pad, or phase reverse on these yet. Gotta do that. And I'm not too happy with my grounding scheme either. The noise floor is a little high for my taste when I'm using it at a place that does not have good AC out of the walls. I really like the star grounding on Peter Purpose's stuff. I'm gonna do that next.
Anyway, thank you, thank you, THANK YOU!!!
