GroupDIY

Project Specific Discussions => Preamplifiers => Topic started by: Igor on February 01, 2009, 11:53:47 AM

Title: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 01, 2009, 11:53:47 AM
Hi people!

Once I took a look on PGA2500 datasheet, it was some years ago,
I said "Hmmm....crap! Another chip pre? Nope!"
My bad taste is discrete, trafo-coupled, colored, etc. I'd cut my hand if I go to build chip-based pre!
Then, I heard evaluation board and said "Hmmmm....Too fast and clean to be truth!"
Many commercial pre's based on this chip appeared on market, like HV-3R, Prism Orpheus, etc.
Most of them are in very high priced range....
Well, there was PGA2500 thread on this forum...
I built a proto and was very surprised.
Studio people who tested this proto wery liked it as well.
This pre deserves name of an excellent clean preamp.
Use poly caps on input and good output stage, this is the cooking receipt.
And yes, it is possible to fit 8 pre's in 1RU.

Here's finnished, tested, fixed and polished final version of pcb's.


(http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_audioSM.jpg)


(http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_contr1SM.jpg)


(http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_ps2SM.jpg)


(http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_pcbsSM.jpg)


More hi-res pics, schematics, comp placement:

Audio board:

http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_audio.jpg
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pre_pcb_top.gif
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pre_pcb_btm.gif
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pre_sch.gif

Controll board:

http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_contr1.jpg
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_contr2.jpg
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_contr3.jpg
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/contr_pcb_btm.gif
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/contr_pcb_top.gif
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/contr_schem.gif

Power supply:

(can handle up to 8 pre's):

http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_ps1.jpg
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_ps2.jpg
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/ps_SCH.gif
http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/ps_pcb.gif

Whole thing:

http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_pre_full.jpg

PCB's hi-res:

http://i251.photobucket.com/albums/gg291/diy33609/PGA2500_KITS/pga2500_pcbs.jpg

Measures:

http://i251.photobucket.com/albums/gg291/diy33609/pga2500_meas.gif

I ordered 50 pcb sets...think they will go fast.

Ordering:  

http://www.groupdiy.com/index.php?topic=29771.0

BOM, support, etc, coming soon.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Svart on February 01, 2009, 12:00:44 PM
I do not see the project listed on your ordering page:  http://www.groupdiy.com/index.php?topic=29771.0

How much will these be?

Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 01, 2009, 12:08:37 PM
Wait :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 01, 2009, 01:35:22 PM
PGA2500 AUDIO BOARD BOM

Qty Value    Device              Parts
CONNECTORS
4            MOLEX-3             +/-U, OUT, OUT1, OUT3       
3            JUMPER 2 PIN        0DB, DCEN, ZCEN             
1            2 ROW 10 PIN          INS                         
1            3.81 PITCH MOLEX6     PS
1   NC3FAH   CON-NEUTRIK_AG_NC3    INPUT                       
1   NC3MAH   CON-NEUTRIK_AG_NC3.   OUTPUT
1            M2 ROW 8 PIN                 SPI

MISC
4        FERRITE BEAD 10MM PITCH   L1, L2, L3, L4
1   100k 25TURNS  TRIM_RJ9W        CMRR

C-CERAMIC PS BYPASS           
5   .1U (47N-224) X50V 5MM PITCH        C1, C2, C6, C19,C20
6   224 (47N-224) X50V 5MM PITCH        C21, C22, C23, C24, C29, C30

C-POLY
2   u47     7.5...10.5MM WIMA      C9, C10
2   1U      7.5...10.5MM WIMA      C7, C15

C-POLY OR SILVER MICA
4   33p      5MM WIMA              C11, C12, C27, C28         
1   100p     5MM WIMA              C13                         
2   330p     5MM WIMA              C31, C32
1   1N       5MM WIMA              C33

C-TANT 10V 2.5MM PITCH
3   10...47U      C3, C4, C5

C-LYTHIC
1   100u_63v   PITCH 5MM         C8
2   220-330UF 35V PITCH 5MM      C14, C16
2   50u 35V PITCH 2.5MM          C25, C26

INPUT CAPACITORS
2   6.8..10u 63v  POLY   CIN11, CIN21
    OR AXIAL/RADIAL LYTHIC 10...47 UF 63V

RESISTORS 0.25W MF 7.5MM PITCH
1   3r3      R-EU_0204/7         R36
4   10r      R-EU_0204/7         R4,R11, R12, R16, R17       
2   50r      R-EU_0204/7         R24, R25
1   120      R-EU_0204/7         R10
1   340      R-EU_0204/7         R6
2   1k33     R-EU_0204/7         R5, R7                     
3   4K7      R-EU_0204/5         R20, R21,R43                         
2   6k8      R-EU_0204/7         R8, R9                     
4   8k66     R-EU_0204/7         R30, R31, R32, R33         
4   10k      R-EU_0204/7         R34, R35, R41, R42                         
6   30k      R-EU_0204/7         R22, R23, R26, R27, R28, R29
2   3M3      R-EU_0204/7         R13, R14

RESISTORS 0.125W NON-MF
4   10k      4X10K PULL-UPS                RN1
4   4k7      R-EU_0207/2V        R37, R38, R39, R40

SEMICONDUCTORS
4   *        1N4148.             D1, D2, D3, D4
4   PN2222 OR     2N3904  Q1, Q2, Q3, Q4
1   78L05     TO-92              IC2                         
1   79L05     TO-92              IC3                                               
1   OPA2604  OR NE5532           IC1                         
1   PGA2500  PGA2500             U1                         
                       
                     
RELAYS
4X NAIS TX2-5V      HPF,PHASE,PAD,48V
Order Code: 1148605
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 01, 2009, 01:35:55 PM
BOM FOR CONTROLL PCB

Qty Value            Device              Parts

CONNECTORS
2    9 PIN PCB INTERCONNECT  M
2    9 PIN PCB INTERCONNECT  F
1    M2 ROW 8 PIN                 SPI
1    FLAT CABLE WITH 2X8PIN CONNECTORS, ~150MM

CAP-CERAMIC
2     0.1-0.22 UF 50V 5MM PITCH      C2, C1
2     15N 50V 5MM PITCH              C13, C14
CAP-LYTHIC
1   220u 10v       3.5MM PITCH       C3
RESISTORS                                                   
13  10k     0.125W 5MM 5%         R8, R9, R10, R22, R23, R24, R25, R28, R29, R42, R43, R44, R45
12  470     0.125W 5MM 5%         R1, R2, R18, R19, R20, R21, R26,R3, R4, R5, R6, R7                             


3       2N3904 OR PN2222                 T1, T2, T3
1   LED3MM           RED LED3MM             CLIP                                                         
1   PGA2500-CONTROLL PRE-PROG'D PIC         U$2

1   4511D            4511SMD                IC4
Order Code: 9666532

3   MEC SWITCH       3F1D MEC            48, HPF, PHS
Order Code: 1132902

3   SWITCH CAP
Order Code: 1132951

1   ALPS_ENC      ROTARY ENCODER         RE
Order Code: 1520809

2   HD-F103      7-SEG CC LED DISPLAY    X1, X10
BLUE: Order Code: 1200600
OR: HDSP-A403, HDSP-A153, HDSP-7503 HDSP-7403 HDSP-7803, HDSP-A803 ETC.
                                                         
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 01, 2009, 01:36:32 PM
PGA2500 POWER SUPPLY BOM

Qty Value     Device         Parts                     
CONNECTOR MOLEX 3.81MM X6                         
1             MT6-6Y         PS                         
                       
DIODES
6             1N4004         D1, D2, D3, D5, D8, D10   
4             1N5400         D4, D6, D7, D9             
2             1N5822         D11,D12

CAPS-CERAMIC
6   0.1       50V 2.5MM         C9, C12, C14, C15, C20, C21
2   0.1       100V 7.5MM         C2, C4                     

RESISTORS
1   10k       R-EU_0207/10   R3
3   200       R-EU_0207/10   R1, R4, R7
1   rx+       R-EU_0207/10   R5 FOR 24V, USE 3K57; FOR 18V, USE 2K7 
1   rx+       R-EU_0207/10   R2 FOR 48V, USE 7K5
1   rx-       R-EU_0207/10   R6 FOR 24V, USE 3K57; FOR 18V, USE 2K7

CAPS-LYTHIC                       
4   100u 50V     3.5MM PITCH  C10, C11, C13, C16         
1   100u63v      5MM PITCH   C5                         
1   33-47u 100v  5MM PITCH C3                 
3   220u 100v    7.5MM PITCH                   
1   1000x10v     5MM PITCH                         
2   3300u        10MM PITCH                         
                         
IC, MISC                       
1   317       LM317TS                               
1   337       LM337TS                               
1   783       TL783                             
1   LM2576_5V                 
1   INDUCTOR 100-150UH 1.5-2A       
2   HEATSINK                                   
                       
                         
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: lofi on February 01, 2009, 02:21:00 PM
thought it was just my sister in law that likes to make big entrances, but no, seems the whole of Israel likes to do this :) :)

stunning (as usual) looks like bankruptcy is fast becoming a reality for me, and looks like i shall put a small marker at your door as partly responsible ;D

Iain
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: nielsk on February 01, 2009, 09:02:20 PM
Now if this had MIDI control so it could be one of 128 units in a remote preamp with digital output my dreams would answered
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 02, 2009, 01:56:36 AM
Maybe in a future :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: 3nity on February 02, 2009, 11:12:47 PM
Why is the cad dollar so low compared to the Euro....i;ll never afford one your kits! :'(
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: chrissugar on February 03, 2009, 04:22:09 AM
This is excellent!
After waiting two years for this, I almost lost hope that someone will write the code to controll the PGA2500. ( http://www.groupdiy.com/index.php?topic=2148.0 )
By the way, the preamp I was talking there was the Lavry Blue mic preamp (based on the PGA2500) ( http://www.lavryengineering.com/white_papers/4496-2-01.pdf ) and it sounded cleaner than some other very good, clean preamps like the Cranesong, Millennia HV3D and DAV.


I have a question Igor.
I have my different idea of designing the front end and the output buffer for this preamp, so I do not need the preamp PCB. There is any chance you can sell only controller boards with programmed microcontrollers? If yes, how much would they cost?
Please, say yes. ;D

chrissugar
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 03, 2009, 04:26:57 AM
Depending on how many boards you need. I have to brake a pcb set for this,
or make a batch of controller's PCB's only.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: chrissugar on February 03, 2009, 04:38:24 AM
Probably 8 for starting but maybe more in time (up to 24). Can you give me an estimated cost?
Many thanks.

chrissugar
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 03, 2009, 04:43:42 AM
For 8 controll boards with PIC's, it will be EUR22/set. For 24 controll boards, EUR17/set.

@3nity: take only pcb's+PIC, and order the rest by yourself,
it comes up a bit cheaper if you don't count in time spent to
order all parts and shipping cost.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: chrissugar on February 03, 2009, 05:05:50 AM
Hmmm, very very tempted to buy 24 from the begining because of the price break. Although I don't know if I can afford at this moment to invest over 400eu only in the controllers.
Will think about it and tell you what I decided.
Thanks again.

chrissugar
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 03, 2009, 05:15:51 AM
No probs, take your time. IMHO it is excellent price :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: chrissugar on February 03, 2009, 06:30:57 AM
After reading again what you wrote here:

I have to brake a pcb set for this,or make a batch of controller's PCB's only.

it made me realise that maybe it is better to ask if you would sell preprogrammed microcontrollers, because that way you don't have to break PCB sets.
Also shipping of the chips would not depend on waiting for PCB fabrication.

Thinking about it, it became clear that it is not absolutelly necessary for me to have the controller board. I will not include the polarity, high pass filter and pad switches in my preamp so I can also make my own simplified version of controller pcb, with only gain control and phantom power.
What do you think?

chrissugar
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 15, 2009, 09:18:00 PM
Bump! People interested in PCB's/kits? Only 4 kits left.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on February 24, 2009, 07:23:26 PM
Wich Toroid do you recommend? some 18 - 0 - 18 at the secondary?
This one here (http://www.banzaieffects.com/Talema-TRT30218-pr-23376.html) will work? 30VA is enough for 4 pres?

Why do you suggest that the PSU could be 18V or 24V? is any related with using NE5532 or OPA2604? please let me know :)

Cheers!!!!

Eddie  ;D
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 25, 2009, 02:38:55 AM
Kits comes with opa2604, my guess is to run them from 22-24V.
Farnell have some nice 2x25V toroids, cheaper a bit than EUR20.
30W is enough.
If 5532 will be used, 18-0-18 will work, just calculate power supply resistors,
for 5532 it should be 18V.
The logic is very simple:

if output is 18V, voltage drop on 200R is 1.25V and on Rx is (18-1.25)V...

(200/1.25)=(Rx/16.75)

Rx in Ohms

The rest is plain math.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on February 25, 2009, 05:51:42 AM
Ok, afterall I prefer the OPA2604 sound against the NE5532, I think it sounds clearer... just to my ears :D
I'm planning to fit a trimmer instead the Rx+ and Rx- resistors, so I can regulate the voltages to the preamp with more precision.
I'll go to the 25 - 0 -25 toroid ;)
Thanks Igor!

Eddie  ;D
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on March 12, 2009, 07:35:17 PM
Hello Igor!
I received the kit thanks!!!!! Great work on this!!!
I have just a question: How is the PGA 2500 and the 4511 pin 1 orientation???

(http://i685.photobucket.com/albums/vv213/samplegod/PGA2500PIN1.jpg)

(http://i685.photobucket.com/albums/vv213/samplegod/PGA25004511Pin1.jpg)

Just one more issue... I'm ordering some stuff from Banzai... I'll go for this (http://www.banzaieffects.com/product.php?productid=23384) transformer for running the preamps... is that ok?

Thanks a lot!!!

Eddie  ;D
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on March 13, 2009, 03:10:07 PM
Yes, exactly as red dot. Bottom control pcb is mirrored on drawing.
For 1...4 pre's possible to take 30W trafo btw, trunny on link is fine for powering up to 8 of pre's.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on March 13, 2009, 07:21:20 PM
Thanks Igor!!!!!
Awesome project!!

Eddie ;D
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on March 13, 2009, 09:06:17 PM
By the way Igor, the two 3300uF caps on the PSU board are 50V or 100V? exist a big price difference between them, just to know for sure...

Thanks,

Eddie ;D
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on March 13, 2009, 10:55:16 PM
No way for 100v!!!
40-63 is enough!
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on March 14, 2009, 07:46:02 AM
Ok! Thanks!!!

Eddie :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on June 25, 2009, 04:36:19 PM
Hello Igor!

I finally finish my PGA2500, but I'm testing the PSU voltages right now and, have one question: I'm using OPA2604, so I need to get around +23VDC and -23VDC for PS-1 and PS-3 right?
I tested and it start to smoke my R3 that is the current limiter for the led, that is connected exactly between PS-1 and PS-3 giving me around 65V! so for sure it will start to smoke! I'll substitute the R3 for a 3K3 @ 2W resistor instead of the 10K @ 0,25W that is described in the BOM.
I'm leaving it open to test!
The PSU values I have, acording with the PSU Schematic are:

PS-1: +23DC
PS-2: GND
PS-3: -23DC
PS-4: +48VDC (phantom)
PS-5: GND
PS-6: +5VDC (for ICs)

Am I right with this tested values?
Thanks!!!

Eddie  ;D
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on June 25, 2009, 04:54:53 PM
Another issue... how should I regulate the 100k trimmer on the audio board? I have no Schematic and don't know what you mean with "CMRR"... and I really don't know about the jumpers... I'm leaving like you have in the photos, but I think is important know what they're for  :-\
Can you post some more information about that??
Thanks a lot for this great project!!!!
Cheers,

Eddie  ;D
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on June 25, 2009, 06:22:44 PM
Hi  Eddie, 10k 1/4w as current limiter for diode worked fine for me...strange. 3k3 is too low.
Here you can find all schematics etc:
http://www.groupdiy.com/index.php?topic=31783.0
(it is better to download schematic first :)
Regarding 100k trimpot on audio board: connect + and - out together thru two absolutely same resistors
(say 10k 1%), at this point should not be signal. Adjust it with CMRR pot for minimum.
Jumpers. Do it as on photos.
In general: if 0db jumper not installed, gain of pga2500 will be 0db.

There's 10-pin (2x5) connector, it can be used as "insert",
balanced in-balanced out, will not work good with unbalanced device.
Install two jumpers, one 7-8 and one 9-10.

A piece of balanced shielded Mogami etc wire will be helpfull to connect
out1 and out1-1, see schem.

Good luck!
 
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on June 25, 2009, 06:26:46 PM
BTW, if you use OPA2604, there should be 46V between PS1 and PS3.
Please check everything is OK before whole thing will smoke.
It is possible to desolder dead pga2500 and install new, but better no :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on June 25, 2009, 07:04:47 PM
Hi  Eddie, 10k 1/4w as current limiter for diode worked fine for me...strange. 3k3 is too low.
Here you can find all schematics etc:
http://www.groupdiy.com/index.php?topic=31783.0
(it is better to download schematic first :)

I used this schematic... I have 46.1 VDC between PS-1 and PS-3. I just realize that having 46VDC dropping 2V for the led, I must have 44V on the Limiting resistor... so, 2V with 0,02A current consumption I'll have:

R = 44 / 0.02
R = 2K2

P = 44 x 0.02
P = 0.88W (1W or 2W is ok) but I think 0.25 isn't  :-\

If my math didn't fail... I'll need a 2k2 @ 1W to limit the current... talking about the other PSU voltages, I think all seems ok then!
I remove the "black" 10k resitor, the led don't ligh up, and everything is normal :)

The link for the audio board schematic is broken... can you get that available?
Thanks a lot Igor...

PS.: man... Michael Jackson has died...what a mess!

Cheers,

Eddie  :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: abbey road d enfer on June 26, 2009, 06:47:29 AM
Juste one question. Does the controller recalls the last settings? Flash memory?
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: abbey road d enfer on June 26, 2009, 12:43:36 PM
Here you can find all schematics etc:
http://www.groupdiy.com/index.php?topic=31783.0
Hi, Igor
I can get everything except the pre schemo
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on June 26, 2009, 09:40:40 PM
Juste one question. Does the controller recalls the last settings? Flash memory?

No... each power on, it returns to "0"

but mine isn't working propertly... don't know why...
Cheers,

Eddie
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on June 26, 2009, 09:50:37 PM
Hey Igor,

I finally finish my PGA2500, but it's not working propertly... the controler board, don't control anything, I pressed them and the top first and the second do the same, activate the phantom... visualy, because I hear no relays switching, and can't measure any 48V on the input's XLR pins 2 and 3. I can't hear no relays switching for the phase and the pad also...

I tested the flat cable, and it seems ok, but the control have a strange behaviour...
The one step db gain, works, visualy, I see the numbers normaly, but the light buttoms are crazy...
I soldered the PGA chip and the other one in the control board by myself... is in any way, clould be some bad soldering for the PGA SMD chip?

I think even it is bad soldered, the unit just doesn't work, bu the control board should be a normal behaviour... isn't it?
Really don't know how to start debugging it :S
Can someone help me please????

Thanks!

Eddie :(
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on June 29, 2009, 04:06:58 PM
OK, litle by little :)

Version of controller in these kits doesn't have a memory. It starts every time from 0.
The reason is if occasionally settings with phantom "on" or high gain stored, it can damage the mic or speakers.

Schematic link works perfect, from my home and work comuters.
It is huge .gif, may not work in Explorer.
Right click, save-as, open with acdsee ot whatever.

10k/ approx. 5ma seems ok for led, except it is not light show...at 20 ma most of led's are too flashy.

Yap, Jackson was Great Personality...never liked this kinda music anyway.

SaMpLeGoD, please let me know if display shows numbers and goes from 0 to 75 with turning the encoder.
Are pushbuttons working? (i.e. lighting their led's)?
Next step check the signals on cs, sdi, sdo, sck of PGA2500 with scope.
Check +/-5V as well.
Be sure 0db jumper is installed.
Be sure "insert" jumpers are installed.


Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on June 29, 2009, 04:08:49 PM
The next step is checking voltages on input/output of pga2500. It should be 0v according to gnd.
Ceck every connection and every solder joint.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on June 29, 2009, 06:34:38 PM
SaMpLeGoD, please let me know if display shows numbers and goes from 0 to 75 with turning the encoder.
Are pushbuttons working? (i.e. lighting their led's)?
Next step check the signals on cs, sdi, sdo, sck of PGA2500 with scope.
Check +/-5V as well.
Be sure 0db jumper is installed.
Be sure "insert" jumpers are installed.

Hey Igor,

The numbers response is ok! they go from 0 to 75 and respond quick in both ways... the pushbuttons light up, but only the third one respond for pressing lightning up... didn't checked with the scope if it actually invert the phase, or even, I didn't check if some audio is passing...
The PB responsable for the 48V (Phantom power) sometimes light up sometimes don't, but the procedure that turns the gain into "0" and goes to the previous gain stored is working, but (I tested with the Multimeter) no phantom appears in the Input's XLR pins 2 and 3. the one in the middle makes the same as the phantom's one, but sometimes lighs up the phantom led, sometimes don't... the clip led is always lighted up... never goes down.

Can this be related with some PGA 2500 bad soldering?

Thanks for the help  :-[

Cheers,

Eddie  :-\
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: iban on July 17, 2009, 12:26:46 PM
Hi Igor!

I´m having problems with the kits. One of them apparently works, but there isn´t output signal in the xlr. Between pin 17 and 16 of Pga2500 there is 2volts with 75 of gain. Then, when I speak into the mic, clip-led shines and the output in these pins drops off.

The reles, buttons leds, 48votls on xlr, work perfectly.

What can I do????
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on July 18, 2009, 10:48:04 PM
OK :)
48V has next logic: it sets the gain to lowest possible, than 48V relay goes on, than gain returned back
to its value. Just kinda speaker protection.

@iban: please see schematic, there should be piece of shielded balanced wire between OUT1 and OUT Molex connectors
and jumpers installed on INS connector, connect: 7and8 , 9and10.
It seems like your pre is working fine (if "clip" lits on on high levels, PGA2500 is alive and well), just missing the jumpers or wire to output XLR.

@SaMpLeGoD: please check polarity of LED's in pushbuttons, worst case you can't fix it, pm me and we'll find a way
to do it.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on July 21, 2009, 05:48:56 PM
Hello Igor,

Sorry didn't reply earlier, but I'm trying to check out the soldering of the PGA2500... after that I'll post some results... althrough the pushbuttons don't do the right thing, all the rest seems to be well connected...
I think there is some problems wth the PGA soldering :S
I'm just waiting for a frind of mine that is helping me with this...
I'll PM you anyways...

Cheers,

Eddie
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: iban on July 22, 2009, 12:47:50 PM
Thanks Igor! My problem was the balanced wire between OUT1 and OUT Molex connectors, I didn´t see it in the schematic.  :$
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on August 10, 2009, 08:54:41 PM
HUH! Great! Tell me how do you like the sound.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: kibadachi on August 16, 2009, 03:09:10 AM
Hi ,


Just wanted to share my experience with the PGA2500 kit.

The sound is crystal clear, dynamic and natural sounding.
I tested this with an AKG 414 BTL II and a Neumann M149. I compared the sound to my Groove Tubes P1, UA LA-610 and a Focusrite ISA 430.
The PGA2500 reveals details i do not hear in my other preamps without sounding EQ'd.  There is not more i can say about it then that you have to try it for yourself.
Now i will go back to finish the final power supply because i was so impatient to hear the sound that i just veroboard'ed a psu to test. I have to start looking into a case because a beast like this deserves a good home ( any recommendations?). When i am done with my recording booth i will put on some samples for reference and comparison.

Compliments to Igor for bringing this quality in design and sound to the DIY community!


Thanks !

Jeffrey

Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on August 16, 2009, 08:46:05 PM
Huh. Finally :) I thought this is abndoned thread.
Thanx Jeffrey!
Regarding the case, I very like Shaeffner's cases. But have to check if this fit front pannel.
Purusha BTW can do really cool cases with silkscreening, holes, etc.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: iban on August 18, 2009, 03:05:42 PM
I´m sorry Igor for no reply before about the sound of the pres. I have not time to test them. First I´m trying to put them in a case. I´ll write some words as soon as I can :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on August 18, 2009, 06:56:30 PM
Hey Igor, I still have no news from my friend, I'm afraid he couldn't solder the PGA2500 propertly, If he don't I'll PM you begging for help... lool

Thanks a lot for your excelent work and patience!
Cheers,

Eddie :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on August 18, 2009, 07:45:34 PM
Let's do next, pay shipping back and fourth, and parts (if needed), I'll fix the pre.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on August 18, 2009, 08:02:11 PM
Yeah sure! I'll PM you tomorrow!
Eddie
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on September 02, 2009, 10:54:31 PM
Hello Igor,

Finally my friend gave me back my PGA2500 with the SMD chip re soldered... he said that he saw it at the microscope and all appears to be ok... I really don't know. Well, I did a small video regarding a PGA2500 test, as you can view in the video, the unit starts ok, all the voltages are ok, I can fully rise the gain from 0 to 75 (maximum) and go back. There's a relay action when I pass from the gain 19 to 20, I think it's ok, it should be some gain stage's relay acting... so far so good, but......
When I press the bottom's push button (phase I guess) I can just hear a relay actingand the PB light's up an down as it should be! ok but the middle button that is supposed to be the Pad button, acts like the 48V instead, when I press it not that but the top PB light's up! and when I press it back (the middle one) it the top led's light disappear... and the one who should be the 48V PB (top one) don't do anything :S
I check the flat cable, the connections the parts all seems to be ok... I don't know if is still something wrong with the PGA chip, or if I get it damage on my friend's resoldering... just don't know ...

I asked on the video but I'll do here, what about that molex 3 pin connectors? what's that for? should I connect between them? I saw the schematic but I'm not sure... sorry... I didn't realize how to regulate that trimmer on the main board, even don't know what's for... please just tell me if with this information you can help me... thanks a lot for your work and patience!

Here's the video link (http://www.sendspace.com/file/qn2miu)

Cheers!

Eddie  :-\
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on September 04, 2009, 08:02:09 AM
Hi Eddie, 48V and PHS buttons behaves wrong, probably, there's a short between pins on pcb.
Check everything again.

Please see schematic. There's an option for insert and power supply,
the INS 10-pin dual row connector close to PGA2500.
Initially I thought to hook here extension to compressor or passive EQ. BTW, it is possible.
Connect (7 with 8 ) and (9 with 10) on INS conector.

There are OUT connectors. Take a piece of shielded balanced cable, Mogami thin cable diam. 3mm will be fine,
and connect OUT and OUT1. 1+  3-   2GND.

CMRR pot. After your pre is fine and passing sound, take two same precision resistors in range 4-10k,
I used 4k99 0.25%. Connect them to output next way: -out---R1---tie together---r2---+out.
Point where r1+r2 connected together watch on scope, feed balanced signal -30db 1kHz to preamp,
 gain 40dB, adjust for minimum CMRR. Balanced signal can be done with DI.

Hope this helps.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: iban on September 10, 2009, 01:16:21 PM
Well, in the next link you can see my rack with two PGA2500 and with another two Access 312 kits. All is right working, but I have to adjust the CMRR in the PGA2500s. I don´t have scope, then, I don´t  know how I will do it  :-\

Thanks Igor for your support!!

http://www.flickr.com/photos/isialdi/sets/72157622330236258/ (http://www.flickr.com/photos/isialdi/sets/72157622330236258/)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on September 17, 2009, 07:04:01 PM
Hurray! Nice build. Will be happy to hear about your sonic impressions.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on October 23, 2009, 10:26:44 PM
Hi Igor, been busy lately! My PGA2500 are alive, all the buttons are working propertly, and the unit is passing audio, but when the gain reach the 20, I start to hear a high frequency sound, that raises with gain of course... at the 19 all quiet, when pass 20 I hear a relay and start to hear that... could this be related with the CMRR relugation? I still didn't regulate that!
Any clue???
Thanks a lot!!

Cheers,

Eddie :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on October 24, 2009, 04:33:01 AM
Hi Eddie, this seems ground problem....please check the grounding scheme and connections.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: iban on October 24, 2009, 07:33:45 AM
SaMpLeGoD, I haven´t regulated the CMRR yet and I don´t have that high frecuency sound.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: SaMpLeGoD on October 25, 2009, 05:22:00 PM
Ahn all right then! Actually I didn't put the preamp inbox, I just tested outside... and of course I didn't wire the ground scheme yet!!
Thanks a lot!!!

Cheers,

Eddie :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on November 16, 2009, 03:43:08 PM
Hello Igor, is your stock for the pga project updated still 6 left? I would be interested in four plus PSU, thanks for clearing this out so i can purchase thanks a lot!
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on November 16, 2009, 03:48:08 PM
I don't have PGA2500 chips right now; full kits...maybe, depending on interest, will be offered in next year.
The PCB's, controllers and PS pcb's are in the stock.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on November 16, 2009, 05:12:07 PM
Ok, you mean 6PCB's left that i will have to solder the PGA by my own right, and maybe another batch for next year for full kit, but no PCB pre-soldered?
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on November 16, 2009, 05:18:50 PM
Exactly :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on November 16, 2009, 06:57:32 PM
Ok, well smd is not a technique i'm very used to, solder paste maybe can do the trick, with oven technique but a little too much for a novice i think  ::), i have a micro solder iron that could do the job, any advice?? how are you mounting it?
I'll be using 63/37 no clean. For doing the job right, i will need to put some solder first on the PCB and then put the Chipset and heat the legs no???, but what about the heat applied for a while until the 28 legs are soldered correcly??  will this cause a problem? I know the quicker the better but just asking... Thanks for helping out...
I was searching for a crystal clear type preamp, and this project is really cool, could build a nice 4 preamp in a 1U in the future, i just want to purchase PCB's before they are gone but haven't thought on soldering the chipset by my own, maybe it's time to try this, but let me think about it and will get back to you shorty, waiting for your advice...
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on November 16, 2009, 07:24:12 PM
Tony, the key is just a good iron with constant temp., 0.4mm solder, good liquid flux and magnification lense. 
Search YouTube or Google for SMD soldering video.
After some time you will find soldering 100-pin SMD chip with 0.5mm step takes same time as soldering 10x 1/4W resistors.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on November 16, 2009, 07:35:05 PM
Yep i was doing search right now, i think it's time to start SMD and i can test my skills before also on some smd resistors etc....
Ok so what would be your total price of 4 PCB's and PSU plus shipping to France then, without microcontroller. Thanks Igor!
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on November 16, 2009, 07:51:36 PM
Ahem... I guess you mean PGA2500 chip. I don't think you want enter into the mess with programming your own controller :)
The price already include microcontroller's price. It is same with or without.
This is BUILD SUPPORT thread. All questions about pricing, etc-here:
http://www.groupdiy.com/index.php?topic=29771.0
or by pm.
Let's keep building thread clean, just think about reading 150 posts to find info you need. Thanx!
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Kir_For_Pleasure on November 16, 2009, 09:36:28 PM
Me likes !!! stunning work !!
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on November 17, 2009, 03:09:17 AM
Sure no problem, thanks a lot
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on November 17, 2009, 09:07:23 AM
Cool than....will be happy to see photos of finnished stuff. Good luck!
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: rob_gould on November 25, 2009, 09:52:54 AM

Can anyone in this thread tell me where they got their PGA2500 chips?

They are out of stock at RS and Farnell in the UK, and Digikey and Mouser in the US, and not available until next year by the look of it.

Igor - know any reliable sources ? ;)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on November 25, 2009, 09:59:32 AM
Really....dunno. Try to ask Rochey.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: 12volts on December 09, 2009, 07:33:35 AM

Can anyone in this thread tell me where they got their PGA2500 chips?

They are out of stock at RS and Farnell in the UK, and Digikey and Mouser in the US, and not available until next year by the look of it.

Igor - know any reliable sources ? ;)


The earliest you'll get any in the UK is the end of January 2010. then only if you ordered in October.
It is the same tale for any of the large UK distributors. They are being rationed too, 6 chips per customer.
This of course puts your order in the higher price band too, currently £22 each !!!!  Good job I bought 12 a while ago.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: rob_gould on December 09, 2009, 07:54:27 AM

Mine are being dispatched direct from TI on 24th Dec apparently.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: bachevelle52 on January 02, 2010, 06:05:41 PM
I got some through TI samples program........8 of them IIRC. Happy hunting.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: janvanvolt on January 07, 2010, 09:48:10 AM
Just ordered the parts from reichelt + farnell. Can't await to get the PCB (and then to finish this lovely project).

Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on January 29, 2010, 05:29:29 PM
Hi Igor, sorry to bother for this, but im having a hard time finding the 2 Row 8 Pin connector with housing  (SP1) for ribbon cable, do you have the Farnell Reference? I've searched on Farnell, Digikey... but can't get my hands on something that will fit. Thanks in advance.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on January 30, 2010, 07:09:29 AM
Finally, seems i found something that will fit, sorry for that, don't know why it was hard for me founding this part  ??? , the most popular starts at 10 pin, this one doesn't have the exact same size of your connector, but i think it will do the job:
http://search.digikey.com/scripts/DkSearch/dksus.dll?WT.z_header=search_go&lang=en&site=us&keywords=609-3083-ND&x=0&y=0 (http://search.digikey.com/scripts/DkSearch/dksus.dll?WT.z_header=search_go&lang=en&site=us&keywords=609-3083-ND&x=0&y=0)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 01, 2010, 06:53:27 PM
Yes, this will do the job, just check twice the pin orientation before connection :)
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on February 11, 2010, 07:39:04 AM
Oh i forgot to ask you something, i've also had a hard time finding the 50uf capacitor for C25/C26, i went for 56uf, i tought that with the tolerance this will be no trouble, but i just want to make sure, maybe i'm wrong? (i'm still a rookie in electronics) but i see that from the schema, these are related to the Common Mode Rejection pot, so changing the value could mess up this part ??? I said to myself electronic is not an exact technologie so.... Thanks Igor

PS: I'm still a rookie, but i have basic electronic skills, good hand and soldering skills and a lots of patience so i don't think this building will be too hard, like everything else beeing careful gets the job done,  so don't worry i'll check everything on my work and infos on prodigy to get my answers, i know that you're a busy man. Thanks a lot Igor
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Igor on February 11, 2010, 09:34:36 AM
Tony, it's OK. These caps can be 47uF as well, like:
http://il.farnell.com/panasonic/eca1vam470x/capacitor-47uf-35v/dp/8767246
(for example, these caps are cheap, but have good performance).
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on February 11, 2010, 09:45:21 AM
Thanks Igor, i already got the 56uf so... but thanks for clarifying.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: janvanvolt on February 24, 2010, 08:32:13 PM
Hi Igor,

i just soldered the 4511D on the board and observing i have a short between PIN 3+4 and 16, Is this intentional or errornous ? I am not able to unsolder the 4511D, so if this is _not_ intentional i kindly ask for another control board. If this is intentional then i probably panicked ...

Also: is somebody able to provide me one PGA2500 ? I am on backorder on Mouser and Farnell AND even TI test supplier.

cheers

jan
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: zayance on February 25, 2010, 04:56:49 AM
Well if this can help you janvolt, i have the same short on pin 3 and 4 of 4511D, but if you take a closer look, you'll see that it's connected to a via which goes to the C2 cap, it's not very clear on the schema, but it works for me, concerning the pin 16, i don't have no short,when you say short do you mean you add too much solder? if that's the case, then you can still suck it up with a solder bread, with the help of flux, there is a video on youtube from curious inventor wich guides you to SMD soldering, it's a good video to solder or repair when you've done mistakes, but as always, if you don't have the right tools, it can be harder, but too much solder is ok to repair, a dead component will be more of a headache, but still it's possible, with Chipquick, don't have that but that can be really a saver when you mess up, you see that on the video also.
http://www.youtube.com/watch?v=3NN7UGWYmBY

Franell has still 9 left, maybe from the french website? Did you ask for more then that?

http://fr.farnell.com/texas-instruments/pga2500idbg4/preampli-pour-microphone-cms/dp/1180156

Hope it helps.
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: janvanvolt on February 25, 2010, 05:36:47 AM
If i have a meter and test pin 3+4 then i get a "beep" ; and 3 or 4 to pin 16 i also get a beep.
i probably was not specific enough :-) i'll look for the PGA on that page then...


Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: lagoausente on August 27, 2014, 02:24:18 PM
I want a kit, still available?
Title: Re: PGA2500 KITS: AVAILABLE. BLACK PCB, SUPPORT THREAD.
Post by: Majestic12 on August 31, 2014, 04:22:25 AM
Igor has disappeared for almost two years now, the chance of still getting a kit is very low.