#melcore

[theratpy]

Creator of rats (self) does jig (on counter) to celebrate (clean kitchen)

Maid May MMXXIII - twitch.tv/theratpy [R-rated]

#melcore #beetlerat #theratpy #about #he they #transmasc

[ronispadez]

I'm sorry it was 2 in the morning when i wrote that. Therefore I was not take responsibility.

G as in Gerard. not J. I will not spell it with a J I prommy

NO it was funny lmao

#roni says stuff #melcore

[sffroncloaked]

just saw p.uss in boots and first off. BANGING movie its so good i enjoyed every minute

second off. mel brainrot returned once more as soon as i saw Death's sickles

#☽◯☾ : bisexuals stay winning : ooc #((i was like 'YOO MELCORE')) #((i neeeeed to draw her in dramatic ass lighting now. for my health))

[mel-core]

✧ ⠀🎧   ،    🦢 .    🧦 ︒．𑁍    𝄒

#been feeling the winter vibes lately #melcore ?! #moodboards #messy moodboards #winter aesthetic #winter moodboard #white aesthetic #white moodboard #coquette moodboard

[mcrrymurdcr]

POV: you fight Melissa and she jumps at you and throws you around like this

#k/orra's scrappiness in a fight (and to/ph too tbh) is kinda how i imagine mel's own scrappiness #she can't bend elements but like. rough and tumble and hella grappling like this? melcore #❧ ｢ general ｣ ⸻ ooc #❧ ｢ general ｣ ⸻ tbd #also yes i found a slowed down gif for this but my point still stands

[where-i-bitch-about-nashville]

Melcor AML-27 restoration/racking 1RU stereo preamp

yoyoyo i got something done! i’ve been stuck on this thing and put it on thr backburner like embarassingly long ago and just went thru and got it back up and working:

Melcor Electronics Corp. AML-27 preamp cards, which were made circa 1965-1969 were sold in this backplane format, ordered or installed with fixed gain they were part of the ‘big green machine’ recording console as well as made with the RCA logo and branding for the same 1731 op amp used on these circuit boards. The 1731 uses 9 transistors. Melcor Electronics Corp/MEC still exists, and they made industrial microwaves and peltier coolers and stuff. MEC sold/ended their audio equipment division in a way that gave rise to Automated Processes, Incorporated, API. They still exist making consoles, and may even still make this format of preamp/line amp cards for all I know. It is 300mm not 500mm though, smaller than the popular 500-series lunchbox format. Anywho, API redesigned this whole thing with improved everything. They came up with the 2520 discrete op amp, which has been made along with its subsequent revisions in later years and is still the backbone of API consoles and outboard gear. The 2520 uses 11-transistors.the 400-17 and 400-20 transformers MEC used would be replaced with the API 2622 and 2623’s on their model 312 mic preamp. Or just the 2623, in the case of the 325 line amp card.

The AML-27 is a perfectly imperfect circuit design, lovely in its time, and it balances all of its various imperfections nicely… nay in an electronic sense, it absolutely juggles the metallurgy (and limitations of the transformer designs), op amp instabilities, feedback, gain, distortion, and overall resonance to make a really awesome fat sound. Compared to the API mic pre, it is much more lows and more third harmonic distortion. The distortion also becomes pretty soft clipping in the high gain settings. The API 312’s feedback lends itself to a more midrangey overall preamp sound. The whole sound comparison just boils down to sounding like the late 60’s vs the API sounding like early 70’s circuits, i dont have much better way to describe it. I read on the now-renamed gearslutz that Melcor circuits are all over the Frank Zappa and the Mothers of Invention album Uncle Meat.

My pair of cards was likely parted out from one of these old MEC backplanes around 6-8 years ago. I have serial numbers 012 and 936, but I have no idea their history before me!

For my part, I removed a PCB card kit build in 2010 that I took apart to rack these up, so everything is sort of prototype quality to get them usable and make sure they work right. It has way too many screw holes and scratched up paint, sharpie, and all kind of mess but so far I recapped the electrolytics, matched the feedback and built Grayhill 1073 12-position rotary switches with 1% metal film resistors for the stepped gain control. It has Bourns output attenuators, 110% shielded pure copper twist wire on all the audio path connections with quad 26ga +/- conductor wires. DC supply is on solid 22ga copper throughout, but retains the original Melcor card power LC filter instead of the diodes that were common on the later API mic pre designs that were based on this. I really paid a lot of attention to grounding, shielding, and cable routing, but turns out I did a terrible job back when I first hooked up the audio lines and need to redo it while spacing the cards out evenly in the chassis.

I got these cards stable up to 65dB of gain! :D I have a plan to get the 70dB stable without having to flip 2 switches, but it will have to wait until I can change to a multigang rotary switch.

So far I’ve fixed the input impedance at 600-Ohms, but I installed switches that will allow for the 3-way 300-, 600-, 1200-Ohm input strapping; i still have to wire that up. There is also already functioning 180° phase reverse, -18dB pad, and 48v phantom power on the input line. In the spirit of the 60’s prototype feel, I just went with directly wired mini toggle bat switches.

The gain and output attenuation knobs are a repro RCA skirted pointer knob scaled down to an appropriate size. The chassis is a 1U Middle Atlantic 8” deep steel puppy I got at Randolph & Rice in 2009 or 10 for the kit build. RIP Randolph & Rice Electronics, I miss them every time I build a thing… I am probably going to paint this with the vintage Melcor logo and the logo silhouette repeated as the eye slit in a stencil and possibly rattle-can likeness of the Big Bad of Tolkien lore, Melkor, aka Morgoth. AFAIK nobody else has seized on the company having a Tolkien themed name in arting up any mic pre builds… does anybody have any good Melkor art they’d want hidden in my rack??

So next I have to polish up my racking Valley People mic preamps project, and build an RCA tube console mic preamp pair from scratch of cobbled together vintage parts and new components. I’m also going to turn an Olsen Color Organ deathtrap box into a multiband filter/EQ, and make a clone Audimation Corp. EQ in an original Audimation EQ rack chassis. haha my work is cut out for me… but the mic pre’s will fill out my setup with a pair or two of every decade of noteworthy and/or Nashville linked sounds. for the early 60’s: something like what was originally installed at RCA Studio B, for the late 60’s: these Melcors, for the 70’s: API 2098 console pre’s modded out to the max for what is in RCA studio B now, the 80’s: Valley People/1979 Loft Audio 800 Console MPA5 made hy Valley People in Nashville, for the 90’s and 00’s: i feel like everyone was using protools and mbox interfaces and stuff that kinda didnt have much of a sound so im throwing in MOTU and RME transformerless preamps, and for the 2010’s: Miktek MPA-201, assembled in Nashville version of a rack pair of 1073 mic preamps using correct NOS transistors with 6 AMI audio transformers, dual metering, and lit relay switches for all the controls. 70dB of clean gain. 🔥🔥 I can pretty much make a recording sound like any of those decades with what I have, or combine it all for a mix with all this richness and character of some sick sounding mic and preamp combinations to do all the hard work up front!

#audio electronics rant #melcor #morgoth #Tolkien #restoration #melkor

[lucisevofficial]

brief reviews of dreamcast games ive been dabbling in:

Seven Mansions: Ghastly Smile: truly bonkers cutscenes. resident-evil-esque gameplay. Cool monster design, nothing super surprising

Radirgy: cell-shaded shmup with a megane swirly-glasses girl. this game fucking rules

Maken X: smt artist? smt composer?? insane plot with alternate dimensions and brain-hopping and a teenage girl with a sword?? also just. jank-ass clunky first person melee combat and platforming. weird but very cool

Napple Tale: ok this one's super neat apparently its got a predominantly female production staff? collectathon 3D platformer with just. a deeply weird and charming cast and plot

#turns out! the DC is a deeply melcore console

[lover-official]

WAIT SHE HAD MARCUS MUMFORD SONG THE LINE "and the ladies lunching had their stories about when you rolled through town"????? She's trying to kill me!!!

#carmina posting #blondie #ts eras tour #anyways this whole tour has been very Melcore

[curufan]

#sorry XD #i wanted to do the polls too #silm polls

[controlledhues]

/ / I LOVE how Melcore this is ughghgh she def has one of these

#[ Headcanon ] #aesthetic #tbt

[ross-hollander]

My aesthetic is stolen gems, iron fortresses, demons of flame and cosmic chaos

I suppose you could call it Melcore

#silmarillion #melkor #Well it's actually pretty goth now that I think about it #More-goth as a matter of fact

[theratpy]

Snacks with the Melby pt 2!!

twitch.tv/theratpy [R-rated]

#melcore #beetlerat #theratpy #he they #transmasc

[arc-carnes]

if i were a cat, i’d spend all my nine lives with you ur parents must be bakers because they sure made a cutie piee are yiu the sun? because you light up my day are yiu music? because i could listen to you all day <33 arw you the first day of april? Because im a fool for you are you tea? because no matter how many drinks there are, i’ll always choose you !! (british rizz

melcore

[atomiumamps]

WA12 mkII mic preamp modifications

This is something I'd intended to post last year before the fire, but hadn't gotten around to. The WA12 is a pretty well-regarded budget mic preamp, being largely a clone of an API312 topology for under $500. I'm not a deep expert on the history of API or the 312 circuit, but the broad outline is there. Warm Audio opted to go with a Melcor 1731 style opamp here, instead of copying a later API 2520, but it's socketed and you can change it (if you do, see the note down at the bottom!). To their credit, they chose a vintage 1:8 input transformer ratio, rather than the 1:10 you see on modern APIs. It's a weird choice that the 'default' mode on this preamp (tone switch off) is 1:4, whereas 1:8 (tone switch on) is the more vintage-correct configuration, but whatever. This post references the current black-panel mkII version, which seems to have a slightly different PCB and layout than the orange-panel mkII.

What mystified me about the WA12 is the bizarre input impedance spec. Warm claims that it's 600 ohms, switchable to 150 ohms with the 'tone' switch on. What?? These are ridiculous numbers -- the vast majority of mics want to see a load of 1k or higher, and most mics will suffer pretty severe signal loss with loads under 600 ohms. And as it turns out, these numbers aren't even correct. It's pretty obvious that Warm just quoted the datasheet numbers from their OEM Cinemag input transformer. Cinemag specs their transformers by the expected source impedance on the primary winding, and translates that by the square of the turns ratio to the reflected source impedance on the secondary winding. So unless the secondary of this transformer is loaded with a 10k resistor, 600/150 ohms is NOT the input impedance of the circuit. Transformers don't have a fundamental impedance. They have an impedance ratio, which is the square of the turns ratio. The load you choose for the secondary is what determines the input impedance on the primary.

The stock input impedance I measured on the WA12 mkII is 1.05k, or 600 ohms with the tone switch in. That's actually fine, much more reasonable than the quoted specs. But it still doesn't add up -- if pushing the tone switch doubles the transformer turns ratio from 1:4 to 1:8 (and increases the gain by 6dB), then I should be seeing an impedance 4x lower when it's pushed, not slightly more than half. The other thing I noticed is that the input impedance measured 1.2k with the pad on, regardless of the tone switch position. A ha -- there's a parallel load on the primary side of the transformer that's loading down the input regardless of how the transformer itself is configured (beyond just the 6.81k phantom feed resistors, which have to be there).

Turns out, Warm wired the pad switch so that the pad resistors (a balanced voltage divider of three resistors: 620-140-620 ohms, R35/37/36) are strung across the input at all times -- whether the pad is on or not. The switch just connects the input transformer to either the outside of the network (off), or to the ends of the 140-ohm resistor in the middle (on). There's no need for that. It's worth looking at the way John Hardy wires their pad switches on the M2, since it's basically the same circuit topology. Without any extra parts, and by just changing how the DPDT switch connects to the two series resistors, the Hardy ensures that the pad is completely out of circuit when it's off, and presents no additional load to the mic.

I rewired the pad to according to the Hardy schematic. Boom, the input impedance was then 3.6k with the tone switch off, and 950 ohms with it on. Those numbers actually make sense. But it revealed a new problem -- the input impedance changed dramatically depending on what frequency I used to measure it (I had only used 1kHz up to this point). Specifically, it dropped to under 200 ohms at 10kHz! I felt that was unacceptable, so I started looking at the load on the transformer secondary.

(For our purposes, the load presented by the discrete opamp can be disregarded, since it's quite high, in the megohm range. I did all my measurements with the opamp removed from the socket.)

API 312s have a "zobel" network on the transformer secondary, which is there to damp the transformer's tendency to ring at high frequencies. On the 'canonical' schematic, the zobel network is a 5.1k resistor off the signal line, in series with a 220pf cap to ground. The zobel is in parallel with the secondary's load resistor -- not shown on the canonical schematic but typically found in the vast majority of old 312s -- which is typically 150k. Note that a 150k load on the secondary of a 1:8 transformer would reflect back to the primary as 150k/8^2 = 2.34k, or 150k/4^2 = 9.37k for 1:4! And in fact, 150k is what the WA12 mkII has (R13). So why was my input impedance still so much lower? The zobel network.

Turns out, Warm has a totally insane zobel network of 910 ohms (R14) in series with a 1.5nF (1500pf) capacitor (C19). That's not a zobel, that's just a straight up dump of treble frequencies. The zobel's turnover is so low that it's affecting the impedance across the entire audio band. It's honestly probably the single biggest factor in the "dark" sound of this preamp, and it's way worse with the tone switch in -- maybe that's why they called it a "tone" switch instead of an impedance switch or gain switch. The extreme values are just not necessary to get the (pretty decent) input transformer to behave.

I experimented extensively to find out what the optimal zobel network actually is for the WA12 mkII, and came up with 4.99k in series with 330pf. That's pretty similar to the canonical API spec. In fact, if there were no tone switch and this transformer could only be used at 1:8, the API values of 5.1k-220pf would be ideal. But the transformer performs significantly worse at 1:4 (again, odd that this is the default mode here), so something a little heavier was necessary. I also ended up reducing the load resistor from 150k to 100k, which helped damp ringing quite a bit. After these changes, there's near perfect square-wave performance in 1:8 (tone in) with a gentle roll-off above 20kHz and no peaking at all. At 1:4 (tone out), there's about 10% overshoot on square waves, but no ringing, and an innocuous +2dB peak at 27kHz that just adds a little bit of 'air' to the sound.

Now, the input impedance is 3.5k @ 1:4 (tone out) up to the top octave, where it drops to about 3k. At 1:8 (tone in), it's 1.05k and drops to 650 ohms at 20kHz. With the pad in, it's 1.2k in all modes and at all frequencies. Very nice! I now basically always leave the tone switch in, using the vintage-correct 1:8 input ratio, which has the best frequency and time-domain response, plus better SNR. If I want a little bit of extra 'air' in exchange for slightly worse time-domain performance and lower SNR, I turn the tone switch off and use 1:4.

If you're going to the trouble of doing this work (really just moving two resistors and replacing two other resistors and one capacitor), it's also a good idea to hand-match a new pair of phantom feed resistors for best common-mode noise rejection. I found the stock 6.8k parts in the WA12 mkII to be about 1.2% apart from each other, when the IEC phantom specification says that it should be less than 0.3%. I make it a habit to match pairs of 6.81k metal film resistors to within 1 ohm (<0.03%) when I'm working on mic preamps. No need to buy parts at those tolerances -- the absolute value isn't important, just find any two in a pile that are super close to each other in value.

Notes on changing the opamp The stock Warm X1731 is fine. It really is! You're almost certainly not going to hear a difference by changing it to something else, except when driven into clipping or at the extremes of treble response. That said, I found something totally bizarre when I dropped a CA0252 opamp into the WA12. C21, the phase compensation capacitor in the opamp's feedback loop, is 12pf. 12pf is not doing anything in this circuit. The API 312 uses 120pf, 10x higher. I have no idea whether this was a board-stuffing error, a CAD/schematic typo that snuck into the BOM, or just a stupid design choice. It doesn't really pose problems with the stock 1731-style opamp, probably because that opamp has much more limited bandwidth than a 2520. But if you drop a 2520 into the circuit, you will get a huge peak of ultrasonic noise around 90kHz. This is enough to screw up your metering if you're recording at 96kHz or 192kHz ("why is my meter reading -30dBFS if I can't hear anything?"). It affects noise all the way down into the audible range, so you will also hear more background hiss with a 2520 opamp than the stock 1731, even if you can't hear the main problem up at 90kHz. The solution, of course, is just to change C21 to the API value of 120pf. You should do that anyway, even if you're not planning to change the opamp.

#mods #preamps #recording

[hifumi-gigolo]

so you are a matenrou fan, and you are also a fire emblem fan. and i think you would like pokemon and vocaloid as well. so it is melcore to me

So that's where the other two are from. Gidndkqks

I'll have you know I do not like vocaloid with actual vocaloid voices (they don't do anything for me) but I listen to lots of covers of vocaloid songs literally all the time so that checks out. I enjoy Pokémon in the way that I like certain Pokémon, the gameplay has failed to catch my interest tho

[mel-core]

✧    ﹒     ♡       ⁺      ៹    ﹒       ♡    ﹒ ⁺      ៹    ࿐

melcore ! melinoe ⨾ eighteen ⨾ she/her ⨾ byf/dni ⨾ main -> @melsuki

⁺ ˚⋆♡₊˚. interaction n spam blog. mainly ask games, random thoughts, n pretty art. will not shut up™️. currently so mentally exhausted i can hear colours.

#navi !