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my new build, VP"512" with front panel DI, pictures! Condenser Microphones
Old 5th September 2011
  #1
my new build, VP"512" with front panel DI, pictures!

I just built my fifth Classic Audio Products of Illinois 500 preamp, I'm calling it the "VP512" because with some pointers from Jeff I implemented a front panel 1/4" Hi Z direct inject input that bypasses the input transformer and goes straight to the non inverting input of the 2520, just like an API 512 or 3124. I would consider this a successful build/modification, but there was this one funky sound I heard in one of my tests, I think it was a mic thing or a cable thing though because all the other tests have been quiet and clean. Oh, and it sounds great. I was missing the API type DI. Without further ado...

the first step is to drill a switch-sized hole in your faceplate and L bracket...I didn't get a picture of that. I clamped them together and drilled through both, using the blue bourns pot and the 1/4" jack for alignment

the second step is to cut the path between the zobel network just after the input transformer, and the non inverting (+) input of the op amp... this is the spot to do it



this is the drill bit with a handle I used to cut the trace. I first made a notch in the center of where I wanted to drill (by hand don't use a power tool!) with a "center punch" tool



here's a shot of the whole board to locate the cut



here's a close up with a flash where you can see the trace underneath the black solder mask. make sure to completely cut the trace in two.



these two gold arrows point to your two new "solder pads" which will be used to wire up the mic/DI switch



I made little loops in the legs of these two components to give an easier place to solder the wires to the switch



it is **IMPORTANT** to relocate the blue and orange leads on the output transformer to the "Opt-Blu" and "Opt-Ora" solder pads that Jeff was smart enough to include on this great PCB, as you can see here. If you don't do this you'll get no output. this step bypasses the usual T-Pad attenuator installation.



here you can see the little jimmy-rig circuit I whipped up on a piece of stripboard, which I conveniently mounted on standoffs from Small Bear (you could just as easily order extras with your CAPI order) using the pre-existing "smaller footprint standoff mounting hole" that you'd use if you were building a VP3124 with four of these in 1RU. I didn't have a 10uF non-polar capacitor so I invented one by soldering the negative legs of two 22uF capacitors together (20 would be more ideal, 20+20 in series = 10uF. 22+22 in series = 11uF in my build) and the positive legs become the new component leads. This will make more sense if you take a look at the 3124 schematic attached at the bottom of this post. there is also a 47K resistor in front of the cap, and that goes to the 1/4" jack tip (green wire on the left). the green wire on the right goes to the switch



here's where I attached my switch wires to my "new solder pad" (bent component loop legs) the loops gave me a place to wrap my wires around for a strong physical connection



here's the 1/4" jack. not an ideal jack choice, it's a very tight fit. something like the square plastic enclosed switchcraft jack would be a better choice. sleeve and ring are both shorted together and go to ground

Old 5th September 2011
  #2
here's ground. you can find ground points on the VP312 schematic from Jeff's website. four of them happen to be the last two eyelets each on the Mute and Phase switches. I used a DPDT switch for my mic/di switch because I plan to use the second pole for an LED indicator at a later date. Jeff pointed me to the LEDs you need here: SSL-LX3044ID at mouser or digikey. You can run them straight off your 48V with a 10K resistor between 48V and the LED. you can add an indicator to your phantom too, which I will be doing for ribbon mic safety more info here: VP312DI, 500/51x Mic Pre + Direct Inject Build Support Thread
**IMPORTANT** you must also solder a 1M resistor to the middle/common lug of your switch (the one that's connected right to the non inverting op amp input) and attach the other end of it to one of the ground points. I'm not sure what this is for? but I would guess maybe to stop loud pops during switching. maybe Jeff could chime in with



here's all my wiring. I'll probably zip tie it together for a little cleaner finish



glamour shot



silly front panel. I'll get around to a finish of some sort later...juts wanted to play the thing!!



I used a Cinemag CMMI-8PCA input transformer, it drops right in with no modification necessary. I just wanted to get a little more modern with the tone of this build. Not that I don't love the EA transformers cuz I do. This one seems a little brighter, on first impression... shootouts will happen later, but so far it's sounding niccce.



tada! I'm pleased. Maybe someone else can give this a try now.

Cinemag takes a while to fill an order, beware of that.

this order is different from a VP312 order in that you need an extra switch, a 1/4" jack of some sort, some wire, and DON'T order the T-Pad attenuator, you'll save some money here, then you need some standoffs, a perf or strip board, two resistors, and one non polar capacitor

here's some relevant documents provided by Jeff to help along with this type of modification. He said the 1K resistor following the 10 uF non polar is not necessary but you can include it. compare to the VP312 schematic, know how a switch works, and you should be on your way. Long live DIY and great companies like CAPI

EDIT: it's also very important during an input transformer substitution to substitute a correct zobel network and load resistor (R2, R3, and C1 in the VP312) to get the sound right. Manufacturers will recommend values for their transformers. The load resistor can seemingly sometimes be altered "to taste." It apparently alters the input impedance seen by the microphone. Read about the whole saga below in this thread.
Attached Files
File Type: pdf 1987-era-3124-schemo.pdf (610.8 KB, 401 views)
Old 5th September 2011
  #3
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dandeurloo's Avatar
Good work! Not sure I would do the mod myself out of personal taste. I like the idea of the designs upgrades Jeff has done and offers as his standard pres compared to modern classic offerings. But its cool you went for it. I wonder if you will like it more then the standard CAPI pres.

PS. The VP312 di is really great.
Old 5th September 2011
  #4
thanks! time will tell on the preference

here's some sound clips just to prove that this thing works, and sounds pretty good. the vocal clip is the one with the "strange noise" that only happened at that moment and not at all during 30 other minutes of recording. still not sure what that was

I'm loving this DI bass sound. it's a cheap SX bass with upgraded pickups from a small builder calle Sheptone I think. I love that kind of "clicky" sound you get from this type of DI. I'm not sure if there's as much low end as an API 3124 (which could be a good thing for my general taste), but the sound is certainly spacious and detailed. I'll have to do a full mix recorded only with this preamp on all sources to see what it really does
Attached Files
Old 5th September 2011
  #5
Quote:
Originally Posted by dandeurloo View Post
PS. The VP312 di is really great.
there's something about the tiny parts involved and the added complexity that just doesn't seem right to me with the spartan API "thing"...hence this build. I'm sure they sound great, however, and hats off to Jeff's work. god, I can't live without those T-Pad attenuators on my VP312 though, a godsend. Automated Processes Inc. should take note.
Old 5th September 2011
  #6
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monkeyxx, looks like some fun. You could try removing the 150k R. Doing so will slightly raise your mic input Z. Might sound more "open". By doing this, the 1M R can go in it's place (R2). The 1M is there to provide a ground reference for the opamp when in DI mode. There will probably be some "popping" when flipping your switch. I recommend engaging the "Mute" before doing so, to be safe.

Also, some opamps will produce some DC offset when in the "straight into the 2520" mode. You should measure this so you know for sure. Just put your DMM to DCV and probe between either end of the zero ohm R to ground. To be safe, you could just put a 470uF cap in place of the zero ohm R. To much DC on the 2503 will destroy it. This is what the 3-pin header and shunt are for on my VP312DI.

Quote:
Originally Posted by monkeyxx View Post
there's something about the tiny parts involved and the added complexity that just doesn't seem right to me with the spartan API "thing"...hence this build....
You probably mean the relays. They are just for switching purposes as I did not want to add a "Mic/DI" switch to the front. One is for auto switching so when a 1/4" plug is inserted into the jack, the preamp is automatically switches to DI mode. No biggie. The circuit itself is not much different than what you built only I also have the "pre 2622" option available which introduces the HiZ Plug-In options.

Best, Jeff
Old 5th September 2011
  #7
Quote:
Originally Posted by jsteiger View Post
monkeyxx, looks like some fun. You could try removing the 150k R. Doing so will slightly raise your mic input Z. Might sound more "open". By doing this, the 1M R can go in it's place (R2). The 1M is there to provide a ground reference for the opamp when in DI mode. There will probably be some "popping" when flipping your switch. I recommend engaging the "Mute" before doing so, to be safe.

Also, some opamps will produce some DC offset when in the "straight into the 2520" mode. You should measure this so you know for sure. Just put your DMM to DCV and probe between either end of the zero ohm R to ground. To be safe, you could just put a 470uF cap in place of the zero ohm R. To much DC on the 2503 will destroy it. This is what the 3-pin header and shunt are for on my VP312DI.

You probably mean the relays. They are just for switching purposes as I did not want to add a "Mic/DI" switch to the front. One is for auto switching so when a 1/4" plug is inserted into the jack, the preamp is automatically switches to DI mode. No biggie. The circuit itself is not much different than what you built only I also have the "pre 2622" option available which introduces the HiZ Plug-In options.

Best, Jeff
thanks for the expert advice, jeff! I did have fun with this one

In your experience would you know if the GAR2520, GAR1731 or ML2520 will produce any DC offset, and how much is too much for the 2503?

Does the 470uF need to be NP as in the 3124 schematic or if not which way should it be oriented?

I was wondering what that 150K resistor was for, thanks, I will have to look into that
Old 5th September 2011
  #8
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jsteiger's Avatar
Quote:
Originally Posted by monkeyxx View Post
thanks for the expert advice, jeff! I did have fun with this one

In your experience would you know if the GAR2520, GAR1731 or ML2520 will produce any DC offset, and how much is too much for the 2503?

Does the 470uF need to be NP as in the 3124 schematic or if not which way should it be oriented?

I was wondering what that 150K resistor was for, thanks, I will have to look into that
Most all 2520 style opamps will have a little bit of DC offset. Typically negligible. However, the DI method you are using will cause more than typical DC offset. I would recommend just trying all of the DOA's you have and taking some measurements. The gar1731 will probably produce the most due to the circuit. Ed recommends no more than 5mA of DC current on the EA2503 primaries. He says that 10mA will probably be fine with the size of the lams but better to be safe. Typically the DCR of the EA2503's primaries is about 8 ohms. So, measure your DC offset with your DMM set to DC voltage. For kicks, lets say you get 60mV of DC at the zero ohm R. Using ohms law, 60mV/8 ohms is 7.5mA of current. A little more than safe but probably OK. If it were me, I would use a cap for this situation. If you put a cap in, the positive should face the opamp since you will probably get a positive DCV reading there.

Now, do some measuring and report back!
Old 6th September 2011
  #9
I think I am going to install the elna and wima caps you used on the VP312DI, don't want to blow up a transformer.

should I avoid the mute switch until then as well? Is that what you meant by "The Mute switch is not very quiet [in the Bo Hansen mode] and we don't want to harm the 2503"?

PS I was not aware until just now that the VP312DI already has a direct to 2520 DI mode, that's cool
Old 6th September 2011
  #10
also do you have any advice on what a switching jack that shorts tip to ground with no plug inserted would accomplish?
Old 6th September 2011
  #11
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jsteiger's Avatar
Quote:
Originally Posted by monkeyxx View Post
I think I am going to install the elna and wima caps you used on the VP312DI, don't want to blow up a transformer.

should I avoid the mute switch until then as well? Is that what you meant by "The Mute switch is not very quiet [in the Bo Hansen mode] and we don't want to harm the 2503"?

PS I was not aware until just now that the VP312DI already has a direct to 2520 DI mode, that's cool
You won't blow it up, you may magnetize the core though. Yes, that's what I meant since there is some DC present on the switch, it will "pop" a little. You can use the Mute switch though. It will not harm anything.
Old 6th September 2011
  #12
Quote:
Originally Posted by jsteiger View Post
You won't blow it up, you may magnetize the core though. Yes, that's what I meant since there is some DC present on the switch, it will "pop" a little. You can use the Mute switch though. It will not harm anything.
oh interesting... does a magnetized core ruin the transformer? in what way?
Old 6th September 2011
  #13
Quote:
Originally Posted by jsteiger View Post
You could try removing the 150k R. Doing so will slightly raise your mic input Z. Might sound more "open".
oh wow, that was the money right there. This slightly opened up the high end for the "zing" I was wanting to hear. Very reminiscent of the old 3124+ now, to my ears, but overall a little leaner and cleaner. So much detail! Curious to see what the DC blocking caps will do to the sound.

It's really easy to lift one leg of the resistor even without unscrewing anything (except the preamp from the 500 rack), since it's a double sided board, you can work from the top...took about 2 minutes and is easily reversible. I didn't try it earlier because I didn't know what R2 was doing, should have asked.
Old 6th September 2011
  #14
my OCD on this topic was haunting me today, but it seems to have paid off. I just wasn't happy so I decided to tweak some more. this time I lifted one leg of R3 to take the zobel network after the input transformer out of the socket. (One could also just not install those two components R3 and C1 to achieve the same thing.) I got this idea after looking at the 3124 schematic from '87 posted above, noticing that this was lacking there. they do have a 160K resistor to ground there, so I put R2 back in place.

it's getting too late to hear objectively, but I think this was the ticket for my preference. the low end seems to have opened up a bit, it's a thicker sound now that I'm hearing, and I like that. I think I'm getting close to the 3124 sound. But with a GAR2520 op amp which I preferred in that unit, anyway.

From the Seventh Circle Audio build document A12 circuit description, I learned that the zobel network is in place in this instance to "flatten the frequency response" of the transformer. I guess taking it out allows more of the transformer's inherent properties to show. hmmm. well I think I'm happy, and getting somewhere.. I plan to build another one like this. sounding great in my initial tests.
Old 6th September 2011
  #15
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jsteiger's Avatar
Remember that the zobel network that's in there is for the 2622. You would have to ask Crimson what is recommended for their particular input transformer you are using. If you are chasing the 3124 sound, why not get a Jensen input? If you do so, inquire what zobel they recommend. I'm sure the particular zobel info is around Prodigy somewhere.

I am still curious about what DC offset you will find.
Old 6th September 2011
  #16
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ScumBum's Avatar
 

Sounds good . Less colored more clean sounding than the VP pres , sounds modern rock . The low end doesn't seem as phat though as the 512 and VP312DI . You said you tweaked things and the low end opened up , did it get bigger ?
Old 6th September 2011
  #17
yes I'm still experimenting with the zobel network, but the low end did get bigger when I took out the network completely, which I think is more suited to the CMMI-10PCA, I am using the 8PCA though, I am going to try the cinemag recommended (same as in SCA A12, too) zobel network and see how that compares.

looking at the 512c photographs on sweetwater.com, you can see on the circuit board that API sometimes uses the CMMI-10PCA input transformer. you'll also notice the cheap components! they're using bottom-dollar capacitors. I guess no one is complaining though because they sound pretty great. My biggest beef with the API is their op amp. I think the GAR2520 (and some others) are much more musical.

here's a few quick clips of the "no zobel" configuration of my preamp, let me know if you can hear the difference. I agree that using the wrong network made the preamp too thin sounding in microphone mode. In DI mode I think there's no difference because that part of the circuit is not being used. my bass guitar itself is a bit on the thin side with the vintage style pickups

I'm pretty excited about this, because, in my mind I'm working with a sound that's superior to but in the same school as the stock API 512c/3124 for a fraction of the price. It's also cheaper than some of the other kits like SCA and FiveFish.

I also still really like the stock VP312, those have a great vintage sound, and I've made some great sounding recordings with them

one small criticism of the CAPI preamps... the Bourns gain pots-- all the ones I have seem a little loose and floppy, the knob wiggles around slightly even though everything is tightly fastened. I think in my next builds I am going to go for the rotary gain switch, which is a pretty awesome upgrade. they just seem quite a bit sturdier
Old 7th September 2011
  #18
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ScumBum's Avatar
 

Quote:
Originally Posted by monkeyxx View Post
looking at the 512c photographs on sweetwater.com, you can see on the circuit board that API sometimes uses the CMMI-10PCA input transformer. you'll also notice the cheap components! they're using bottom-dollar capacitors. I guess no one is complaining though because they sound pretty great. My biggest beef with the API is their op amp. I think the GAR2520 (and some others) are much more musical.
I don't think the 512c's sounds great . I sold mine . They sounded harsh and bad to me .


Your monkey512x pre is sounding pretty damn good ! I'm impressed . I think the low end got better and bigger . Maybe you should start your own line of gear with the monkey512x being the first pre .
Old 7th September 2011
  #19
hahaha the thought did cross my mind...and that's a great company name you thought of. I'd have to design my own circuit board and make minor adjustments, but there have been worse ideas.

the fun of building and modding things in a way pays off in known designs that are repeatable.. not quite on the level of a ground-up circuit design, but, there are plenty of companies that get started this way and grow their skills at the same time as their business

it would be fun to decide on "a look" too. naming things is kind of hard though for me. I'm also terrible at being a businessman


Quote:
Originally Posted by ScumBum View Post
I don't think the 512c's sounds great . I sold mine . They sounded harsh and bad to me .
that's what I thought until I put in some GAR2520 in the 3124..it came to life with that simple substitution
Old 7th September 2011
  #20
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Since its modern sounding , I could see a black faceplate but with silver and yellow letters , yellow representing the banana .
Old 7th September 2011
  #21
Quote:
Originally Posted by ScumBum View Post
Since its modern sounding , I could see a black faceplate but with silver and yellow letters , yellow representing the banana .
haha that's great!

this three-day obsession is driving me near-mad, with the test playing and listening involved. I think I'm going to take a break from preamps for a day or two.

on the plus side I think i've reached a resting point, using the cinemag-recommended zobel network and loading resistor. here's some quick clips of that, with the VP312 on the same sources for rough A/B comparison. I'm really wanting to hear what happens with drums and electric guitars, but that will have to wait a bit. I'm hearing a slightly more aggressive and cleaner sound in this one vs the stock VP312. the cinemag-recommended zobel network and load resistor seems to have flattened the mids and opened up the top and bottom a bit. I'd like to read up on this and find out what is actually happening with the impedance and frequency response

EDIT: I can't upload to gearslutz right now I'll have to post clips later
Old 7th September 2011
  #22
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The last to samples nailed it - sounds great man - congrats!
Old 7th September 2011
  #23
Quote:
Originally Posted by greatgreatriver View Post
The last to samples nailed it - sounds great man - congrats!
thanks. that was a cool sound... I think I'm liking it even more now though. here's acoustic guitar and vocal with the same instruments and mics, but the preamp has had an altered zobel network and load resistor as described in the post above, since the previous sound clips. subtle difference, I think you get a little more "punch" this way
Attached Files
Old 7th September 2011
  #24
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cheu78's Avatar
Quote:
Originally Posted by monkeyxx View Post
looking at the 512c photographs on sweetwater.com, you can see on the circuit board that API sometimes uses the CMMI-10PCA input transformer. you'll also notice the cheap components! they're using bottom-dollar capacitors. I guess no one is complaining though because they sound pretty great. My biggest beef with the API is their op amp. I think the GAR2520 (and some others) are much more musical.
+1..

Really? I think that the opamp doesn't make a huge difference soundwise, there is for sure, but it's subtle in this design.. I mean changing xformers yeld for a more audible result IMO.. sure the GAR2520 are no slouch at all..

I changed the input and output xformer on my 512 with some cinemags, for me was a big difference (used the cmmi8 on the input).
Also took off those crappy caps in front of the input xformer.. heh
replaced it with a null resistor..
Sounds better to my ears now, with a nice low end.

We've also built those for our studio (bottom of the page): JLM Baby Animal
You need to be logged in to be able to see the pics though.. took very looong to make that way but it was worth every day spent IME...

Sorry for the small derail..

Ciao

Cheu
Old 7th September 2011
  #25
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ScumBum's Avatar
 

Quote:
Originally Posted by monkeyxx View Post
thanks. that was a cool sound... I think I'm liking it even more now though. here's acoustic guitar and vocal with the same instruments and mics, but the preamp has had an altered zobel network and load resistor as described in the post above, since the previous sound clips. subtle difference, I think you get a little more "punch" this way
Sounds really good , clean , big modern sound .

It doesn't sound API to me . It sounds like it has its own thing going . Sounds pretty balanced from low to high not so mid rangey like the typical API sound .

It would be cool to hear a whole song recorded with it .
Old 7th September 2011
  #26
here's a note from David at Cinemag:

"Most people don't bother with the Zobel network for the CMMI-8PCA. It is taming a small (~1dBu) peak beyond 20kHz. I don't know of many people who can even hear the difference at that frequency no matter how hard they try."

so it looks like I was just hearing the difference in the various load resistor values, not so much the zobel network

yes it's funny all the different permutations of the "API sound." I would guess most people are familiar with the modern 512c type sound and use that as a benchmark. I was surprised when I first got the VP26 and VP312, because they didn't sound like that. I would love to spend some time with a vintage API and see how they all compare.

I agree with your comments scumbum. yeah, this one's not as midrangey as typical 512c... I still think that a whole lot of that comes from the 2520 selection. I'm still hearing a lot of clarity and depth (room sound) but with transformer coloration, and the aggressive midrange character, and that makes me really happy.

here's some more clips for reference. This is a stock CAPI VP312 with the same mics and sources used above. I've also attached a song called "close to my heart" which was tracked through an API 3124 with GAR2520 op amps. that recording was the moment that made me go "aha" and is the sound I've sort of been chasing since selling that unit to fund a 2247 SE purchase.

I think the VP312 is ever so slightly "warmer" and "laid back" than the modified one. I think the 3124 sounds a little phatter in general, but with a similar openness in the highs to my "512." anyway that's just what I'm hearing, comments welcome
Attached Files
Old 7th September 2011
  #27
Quote:
Originally Posted by cheu78 View Post
+1..

Really? I think that the opamp doesn't make a huge difference soundwise, there is for sure, but it's subtle in this design.. I mean changing xformers yeld for a more audible result IMO.. sure the GAR2520 are no slouch at all..

I changed the input and output xformer on my 512 with some cinemags, for me was a big difference (used the cmmi8 on the input).
Also took off those crappy caps in front of the input xformer.. heh
replaced it with a null resistor..
Sounds better to my ears now, with a nice low end.

We've also built those for our studio (bottom of the page): JLM Baby Animal
You need to be logged in to be able to see the pics though.. took very looong to make that way but it was worth every day spent IME...

Sorry for the small derail..

Ciao

Cheu
wow, that baby animal build looks great! I didn't know you could fit that many transformers in a 1U case, nice work.

those caps in front of the input transformer, the 1000pF, aren't those to filter out noise? did you notice any increase in noise floor?

the parts I'd be concerned with mainly would be the coupling capacitors between stages. from building effects pedals I learned pretty quickly that there's a difference in quality of sound depending on the brand and model of cap you might choose in these positions, with capacitance values being equal. in some cases it's quite noticeable
Old 7th September 2011
  #28
one last thing, I have also read that if you use a higher turns ratio transformer, like the 1:10 CMMI-10PCA for example, you'd be getting a few more dB of gain from the transformer itself than the EA 2622 or CMMI-8PCA. This would give you more total available gain, for ribbons and whatnot, and since your gain knob would be lower at the same gain settings (compared to a 1:7 or 1:8 transformer) you'd be driving the 2520 a bit less, so you'd be getting a bit less op amp coloration. you'd also have a higher gain at the minimum setting, so I could see the pad and attenuator coming in handy in this scenario. you could also use the attenuator to drive the 2520 more, of course, which I have finally tested and found out that that's a good sound difference option to have and be aware of and use. You lose that in a build like mine with the DI, but in the CAPI VP312DI you don't, there's DI and attenuation in that one.
Old 7th September 2011
  #29
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Listening to the clips to compare , the monkey512x sounds like a modern pre , little brighter but still balanced from low to high .

The VP312 sounds more like a classic analog album from the 70's . Warmer , old school vibe , lots of mid range .
Old 8th September 2011
  #30
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cheu78's Avatar
Quote:
Originally Posted by monkeyxx View Post
wow, that baby animal build looks great! I didn't know you could fit that many transformers in a 1U case, nice work.

those caps in front of the input transformer, the 1000pF, aren't those to filter out noise? did you notice any increase in noise floor?

the parts I'd be concerned with mainly would be the coupling capacitors between stages. from building effects pedals I learned pretty quickly that there's a difference in quality of sound depending on the brand and model of cap you might choose in these positions, with capacitance values being equal. in some cases it's quite noticeable
Thank you!
When we started, we were worried on about how making those output xformers fit... but it's possible!! heh LOL!
I wanted a 1RU 8 channel xformer in and out preamp..nothing is avalaible on the market, at any price, in 1 RU..

The preamps sounds very good, great input & output xformers (both from Cinemag), and the 2520 opamp is built after a Melville 2520 (at least afaik).

The Baby Animal pcb was slightly modded to make it work like an API circuit, but without the PAD affecting the impedence when engaged (hence the sound change when engaged).. another problem that some users are noticing..

No noise on my jlm preamps nor the 512c that I modded, I thought these caps were there because of an old design.. I think the caps were used to tame the strong ringing on some input xformers...and/or protecting the opamp in case of a short.. btw no noise on my units..

I tried the 512 with a wireless ribbon and I did not notice any noise (was just a quick test though).. btw the gain level was pretty high.. Btw even with ribbon I never ran out of gain (I used it also with a Coles 4038 on vocals).. almost on the end, but still not noisy in any way (and I had some more gain left)..

I strongly agree with you about different caps having a different sound..
It also depends on what part of the circuit they're used of course.. but I prefer the Panasonics more for the upper frequency range (hi's in general are sweeter with those IME) and wima's for the lower frequency range (tight, nicer lows).. YMMV

Bests,

Ciao

Cheu
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