[BUILD] CAPI VP312DI~500/51x Series~Preamp + Direct Inject~Official Support Thread
- Thread starter jsteiger
- Start date
Help Support GroupDIY Audio Forum:
That is normal for red dot so no problem there. Just send me an email thru the store and I'll send you a new cap. I would suggest NOT using the DI on post 2622 mode unless the output is cap coupled.
Hallo everybody, I need some help
Yesterday one of my CAPI 312 almost went on fire!!! :'( :'( I had 2 VP28 in the first slots, two 312 and a LC53 in the fifth slot. I had this pres up and running since march, so three months of great work. Suddenly, after one hour of work smoke start getting out one of the 312...as you can see in the pictures the GAR 2520 is gone
........ the output transformer was really hot. I checked if something else was black or broken, but I can't see anything damaged or hot on the main board.
The 312 was cabled in a patch bay but I wasn't using it, I was using the VP28s and everything was ok. I turned off the PSU, get the damaged module out and then tested all the other ones. Everything was working as usual. The fuse on the PSU didn't blow. My question is : what the hell happened since I used it for three months and didn't move or changed anything?
Can anyone suggest me what to check before puttin' in another 2520 ....
here are the other pictures:
http://s827.photobucket.com/user/technoteo/library/Gar2520%20Blown
Yesterday one of my CAPI 312 almost went on fire!!! :'( :'( I had 2 VP28 in the first slots, two 312 and a LC53 in the fifth slot. I had this pres up and running since march, so three months of great work. Suddenly, after one hour of work smoke start getting out one of the 312...as you can see in the pictures the GAR 2520 is gone
........ the output transformer was really hot. I checked if something else was black or broken, but I can't see anything damaged or hot on the main board. The 312 was cabled in a patch bay but I wasn't using it, I was using the VP28s and everything was ok. I turned off the PSU, get the damaged module out and then tested all the other ones. Everything was working as usual. The fuse on the PSU didn't blow. My question is : what the hell happened since I used it for three months and didn't move or changed anything?
Can anyone suggest me what to check before puttin' in another 2520 ....
here are the other pictures:
http://s827.photobucket.com/user/technoteo/library/Gar2520%20Blown
Was the opamp fully seated? http://classicapi.com/catalog/DOA_Install.php
I would post on the gar2520 build thread or better yet start a new thread. I would assume the issue is opamp related not necessarily a module problem.
I would post on the gar2520 build thread or better yet start a new thread. I would assume the issue is opamp related not necessarily a module problem.
SL2520's require +-16Vtechnoteo said:Just discovered that gar2520 cannot be mounted on the 312 with 24V rail
What am I supposed to use instead of Gary's DOA? red/blue dots?
Can just use +-16v selection in the vp312? should be switchable, no?
If interested in 24v opamps, check out
JLM http://www.jlmaudio.com/shop/index.php?_a=viewCat&catId=17
JH990 http://www.johnhardyco.com/990OpAmpDetails.html
hairball 990 http://www.hairballaudio.com/shop/product_info.php?cPath=37&products_id=132
APP http://groupdiy.com/index.php?topic=33576.0
However, i suggest doing some research on the impedance of the 312/2622 xfmr and the 990c, I have used 990c's in 24v w/ the vp312s and some weird things happen w/ the DI options, but otherwise sound pretty great to me. Been my tom mic pre setup for a while w/ GREAT results.
taliska
Well-known member
qmp audio said:SL2520's require +-16Vtechnoteo said:Just discovered that gar2520 cannot be mounted on the 312 with 24V rail
What am I supposed to use instead of Gary's DOA? red/blue dots?
Can just use +-16v selection in the vp312? should be switchable, no?
If interested in 24v opamps, check out
JLM http://www.jlmaudio.com/shop/index.php?_a=viewCat&catId=17
JH990 http://www.johnhardyco.com/990OpAmpDetails.html
hairball 990 http://www.hairballaudio.com/shop/product_info.php?cPath=37&products_id=132
APP http://groupdiy.com/index.php?topic=33576.0
However, i suggest doing some research on the impedance of the 312/2622 xfmr and the 990c, I have used 990c's in 24v w/ the vp312s and some weird things happen w/ the DI options, but otherwise sound pretty great to me. Been my tom mic pre setup for a while w/ GREAT results.
Don't have vp312s myself, but I think this DOA might work at 24v too (well it says it will with three resistor swaps):
http://www.whistlerockaudio.com/cart/index.php?main_page=product_info&cPath=35_39&products_id=106
Don't know much about the jensen 918s, but I'm loving the DIY990s in my Lola, so I figured I'd try the "older brother" in my vp26s and if I prefer them to the gar2520 then I'm going to mod them to work at 24v and build some vp312s to put them in... (Trying to fill more 24v slots in my 51x racks!)...if they're not my thing, then I'll probably look at the JLM instead...
The 2622 is a 1:7 input transformer. Not that a 990 won't work with it but it is not ideal to plug a 990 into a typical API style preamp. John explains his reasoning behind using a 1:2 with the 990 in his preamps here https://www.youtube.com/watch?v=4si5gljy6AA
As always, YMMV 8)
As always, YMMV 8)
taliska
Well-known member
jsteiger said:
Ok, watched the video and understand his comments about bandwidth, though I'm not technically knowledgable enough to know how that interacts with 990 style op amps, so I'll defer to your greater knowledge!
I'll continue looking around for other DOAs that can run at 24v. I've already got a JLM LA500, so I've already got a 99v I can test at some point (which has already been mentioned as a good match in this thread, but surely is a 990-style op amp also?), but I'd like to see if there's anything else about... (it's not really an immediate problem...I'm looking to switch to vp312s at some point so I can free up the 16v my vp26s are using...)
Did some googling and found this page which is quite useful:
http://www.eisenaudio.com/diy500/tables/opamps/
and clicked through some links arbitrarily and noticed that there are two 2520 style DOAs that expect high impedance and work at 24v (there are probably more, these are just the first couple I checked because I recognised their names!):
http://www.soundskulptor.com/uk/sk25.html
http://www.seventhcircleaudio.com/OpAmps/sc25_about.htm
It's good to have options...
I'm wanting to install Cinemag input trannies and thought i'd drill 2 holes for zip ties, around the 51x text area. See photo for location. It appears that along the left edge portion in the photo is the ground plane. Any one see a problem with this?
edit: the photo got flipped sideways, so I edited description to make sense.
edit: the photo got flipped sideways, so I edited description to make sense.
Attachments
I have done similar things on other projects, but I usually take a piece of perfboard, and put a few pins in it, and mount the trafo to the perfboard (zip ties and hot glue) and then mount it like the regular trafo using the pins. Usually you can make this work.
I mostly use DB25 male connector pins (loose ones) but you could use a diode led or any solid wire really.
That way you don't damage the main board, and you can keep the leads short.
You do have to watch "total height" to make sure you stay within the 500 series module dimensions.
I mostly use DB25 male connector pins (loose ones) but you could use a diode led or any solid wire really.
That way you don't damage the main board, and you can keep the leads short.
You do have to watch "total height" to make sure you stay within the 500 series module dimensions.
Patrick from Davis
Well-known member
Whelp, I got a problem. I get the mic signal through fine and clean. I get a bass through the DI and it sounds great. But... The 48V fuse on my 51X power supply went. I don't know when, but I am assuming immediately. I checked between the 48V and ground on the card edge and of course continuity. Grrr. The build was an odd one. During the build the retina in my left eye detached, so there was a bit of a pause in the middle. Everything is going a good as expected for me, back to the build. I also had soldered the small sub board with the DI switches on the wrong side. I used my Hakko to unsolder it and put it on the correct side. I am hoping that there is not a short between the two boards that would cause this. Any ideas for how to track this down would be greatly appreciated.
Also, I got the gain switched version and the switch goes one more step beyond what the face plate shows. It is Rev C.1 and the switch did not have holes to put pins in. Thanks in advance.
Patrick
Also, I got the gain switched version and the switch goes one more step beyond what the face plate shows. It is Rev C.1 and the switch did not have holes to put pins in. Thanks in advance.
Patrick
There are 12 gain steps with Grayhill option. You can have either a "hidden" step at the full CW or full CCW, whatever you prefer.
Check the chemo for the board to board pads that get the small leads soldered to them. It sounds like you make have a short there for the 48V.
Sorry to hear about your eye. That sounds crazy scary! I hope things are OK for you now.
Check the chemo for the board to board pads that get the small leads soldered to them. It sounds like you make have a short there for the 48V.
Sorry to hear about your eye. That sounds crazy scary! I hope things are OK for you now.
Patrick from Davis
Well-known member
I'm doing well with the eye, but there is still a gas bubble in it, part of recovery. It kind of makes it like having a goggle on that is half full of water. But, you get used to it. And it definitely could be worse. Oddly enough the black solder mask makes things hard to see, but I'll find it. Does the small board (with the 14" jack assembly) attached to the main board have the 48V going to it? I get continuity between the two anchoring holes that are closest to the relay board and the outside edge. I removed the solder and pins with the Hakko and it still gives continuity. If that is by design, then I'll keep hunting. Currently I have not come across anything, but I'm getting the iso propyl out to start cleaning.
Patrick
Patrick
galaxis5757
New member
- Joined
- Sep 17, 2013
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Hi there,
First: Sorry for my terrible English. But I will try. ;-)
A few years ago I did built two VP312DI Rev. C.1 for a friend.
Now I have them back, and one has a problem.
It doesn't matter in which position the preamp gain switch is set. (Stepped gain)
Signal stays the same.
I looked at the soldering of the resistors and the switch but they all seems to be okay.
Does anyone have an idea where to look to find this error?
Greatings from Holland.
Huub.
First: Sorry for my terrible English. But I will try. ;-)
A few years ago I did built two VP312DI Rev. C.1 for a friend.
Now I have them back, and one has a problem.
It doesn't matter in which position the preamp gain switch is set. (Stepped gain)
Signal stays the same.
I looked at the soldering of the resistors and the switch but they all seems to be okay.
Does anyone have an idea where to look to find this error?
Greatings from Holland.
Huub.
Patrick from Davis
Well-known member
Well I got the Sub DI.1 Rev A board off of the main board, and the short is gone. However the BB8 pad is toast on the Sub DI board. Any suggestions for adding a jumper so that the 48V passes properly? I have to clean the board up a bit and then try to figure out if there is a short on the board, or if it was the attachment.
Patrick
Patrick
The 48V track just passes across the Sub board so locate the proper BB pads for it and solder a jumper wire.
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