Its true, I'm still not done with the prototype.  Its really taken much longer than I had expected.  I don't want to rush this though.  Trinity is really kicking ass and its super close to done.  Its actually inspired me quite a bit to do some cool stuff - like build a vintage-style tube console.  I have learned much along this journey and it really excites me for the future.  Joe, from Bamboo Room Studio's is the first supporter and investor of this project, so I would like to thank him again for his patience and support.  

Upon testing today, the preamp exhibited 70dB of gain with the Baxandall passive EQ engaged (a big source of volume loss).  That's a milestone, but yesterday the preamp was oscillating when I turned up the volume too much.  Fixed that as well.  Just needed more shielded wire inside.  Also, the noise is practically non-existent.  The tone is pretty good and probably even awesome by most standards, but I would like it to be a little less colorful and a bit more perfect.  Unfortunately, that will come at a price.  Todays tests were conducted with no negative feedback in the signal path.  By employing some negative feedback I'll be able to get the preamp sounding less colorful and more pristine, but at the cost of gain.  Its completely variable and can be adjusted to taste, but I fear that it will dip into the 60dB range or lower once I have it sounding the way I really want it to sound.  I'm trying my hardest to avoid having 3 tubes per channel - it currently has two.  That extra tube per channel would require a much more expensive power supply, the extra pair of tubes, and additional resistors, caps, wire, labor, etc.  I really don't want to see this thing escalate into ultra expensive land.  In the end I will do whatever is necessary to get it sounding exactly the way I want... and I am damn picky.  Tomorrow I will dial in some negative feedback to taste and hope the overall gain of the preamp stays at or above 60dB.  Fingers crossed.  

You may have heard about the mic preamp/channel strip I've been designing if you follow this blog or the LBA Facebook feed.  It has been a rough battle and at times, like yesterday morning I have felt so completely frustrated.  The difficulty has been trying to find a balance between all the traits I want it to have.  Low noise, High output volume (70dB minimum), wide and flat bandwidth, low distortion, and an equalizer that works well.  It has been a serious challenge to meet all of these design goals, which is why I have tried every single amplifier topology I could possibly think of and even a few I couldn't (lost count, but easily +50 different designs).  There was one design that I drew up a schematic for because it exhibited most of the traits, but it had a little too much noise at full volume, only had 60dB of gain, and there was significant insertion loss upon engaging the EQ.  That preamp design I have thought about going back to because I could not, for the life of me, come up with something that could outperform it until last night.  Finally, I feel like I achieved success.  I will be doing elaborate testing today to determine its actual performance specs, but this new design exhibits all the traits and sounds absolutely fantastic!  I was very pleased and then I engaged the EQ.  It would have been impossible for me to have a wider smile on my face.  WOW, now that's an equalizer!  This is a Baxandall shelving EQ - passive of course, because that's how I roll.  The bass is deep, the treble is high and its damn sexy sounding.  The way that I designed this one, there is no audible insertion loss from turning on the EQ, but rather it was slightly louder.  The EQ circuit has its own triode powering it (1/2 of a 12AX7).  Bypass the EQ and you have one less triode in the circuit.  One might think you could lose a little something good or gain a little something bad by having an additional gain stage, but that couldn't be more wrong.  Since the EQ was slightly louder I wanted to dial it back, but I did it in the best way possible - negative feedback.  Using just the right amount of negative feedback in the EQ circuit I was able to match the volume bypassed to active.  The major benefit to using feedback this way is an extended frequency response and lower distortion, which counteracts the negative effects of having another gain stage.  I feel the sound is as close to perfect as God will allow.  I have decided to go with this design even if the gain is a little on the low side, which it may very well be.  Upon testing later today I hope its in the 70dB ball park, but I will be satisfied if its as low as 65dB.  

Here are the current features of Trinity, though some things may change:

• Two channels, each with 3 inputs.  Mic, Line, and front panel DI.  The Mic/Line is a switch on the front panel, with one XLR in/out per channel on the back side.  
•  Triode powered throughout.  The input is a single triode (1/2 12AX7) per channel, followed by a 6922 dual triode output section.  Engaging the EQ adds one more triode - the other 1/2 of a 12AX7.  4 tubes total in this box (2 per channel).  
• Switches for phase reversal, EQ in/out, phantom power, mic/line, low cut filter, and frequency selectors for the EQ.  
• Dual analog VU meters
• The EQ section is a passive Baxandall shelving EQ with 2 frequency choices for bass and 2 for treble.  The low cut is inductor based, which is far more expensive to implement than the common capacitor based low cut, but it allows for a steeper cutoff slope.  Its effect starts to be realized at 75Hz, but becomes obvious at 50Hz.      
• External power supply for low noise operation. 
• This will be the first LBA product which utilizes solid state components, although the solid state stuff is completely limited to the power supply only.  The heater filament power section is DC powered and regulated for quiet, hum free operation.  This and the high voltage B+ are silicon diode rectified, which to my ears creates tighter sounding lows and more focused imaging.  The B+ regulation holds true to the LBA way of neon tubes, of which there are two.    

Trinity has me really thinking big.  Mixing board big!  I can imaging having four Triinity-style units connected to a summing network with pan controls and a makeup amp for a very serious 8 channel tube Mixer.  Believe me, that is absolutely coming up!  I just need $10,000 first!  lol.  

Heads up to anyone considering buying Sovtek EL84 tubes... I'm building a stereo Hi-Fi tube amp for my home and decided to save some money by utilizing as many things in my stash as possible.  I had a brand new pair of Sovtek EL84 tubes from several years ago (probably from a guitar amp I re-tubed for someone and maybe they changed their mind about the tubes and wanted something better, IDK).  Anyway, I needed a second matched pair so I could use them in my hi-fi amp.  I first ordered a pair from www.tubesandmore.com and tested them when they came in.  Much to my amazement, the grid leakage test for the tubes did not go over very well.  While they passed this test, it was not by much.  I contacted the store and arranged for an exchange, citing the test results.  The next pair came in and I tested them.  I was blown away when one of the tubes actually failed the grid leakage test!  Can you believe this?  A brand new tube actually tested bad.  Frustrated, I returned the tubes for my money back and took my business elsewhere.  I went to tubedepot.com, who I have purchased many tubes from over the years and never a problem once.  When I placed this order with them, I cited in the customer comments section of the order my terrible experience thus far and asked if they could please check the grid leakage before shipping the tubes to me.  When the tubes arrived I tested them again.  The first tube passed everything with flying colors and I was starting to feel relieved, until I tested the second tube.  During the grid leakage test this tube become unstable and began to read in the "?" area of the test range, which for all intents and purposes indicates a bad tube.  Are you freaking kidding me?  I specifically asked for the grid leakage to be checked before shipping these.  I'm sending these tubes back and asking for my money back.  This time I will cut my losses and buy a quartet of much higher quality tubes in hopes on not having to go through this crap ordeal anymore.  

I'm not sure who is at fault here, but I suspect its a pile of fault starting with Sovtek and ending with the dealers not testing there tubes sufficiently before shipping them.  If I didn't have a tube tester I would be a victim of tubes that failed within a month or less, leaving me in a situation where I would have to buy more tubes and if I was a person who didn't know how to bias my amplifiers I would also have to pay to have a tech do that work for me each time.  What a nightmare.  Word to the wise, Sovtek tubes are garbage and the stores don't do extensive testing, so buy the good tubes and you'll be okay.    

After building 4 completely different preamp topologies and several variations of each (roughly 30 total design variants), I finally found "the sound."  I have been searching for this sound for a while, so its a huge sigh of relief having now found it.  I'm not sure what the preamp will be called, but its still a long ways off from production.  This is a 2 tube per channel design, which uses a 12AU7 (same tube as used in LBA FX pedals) and a 6922.  It has an external power supply with a secondary solid state regulated supply for the tube heater filaments to ensure the lowest noise possible.  The preamp currently has so much gain (clean boost) that I have to consider it overkill.  I'm sure it would work great for ribbon mics, but it has a bit of noise that I'll need to clear up first.  One of the topologies I tried out had roughly the same amount of gain, but better control over the gain and practically no noise.  While this other topology had these benefits, it didn't have "the sound."  This sound I speak of is the elusive magic tone that sounds extraordinarily life-like and fluid.  It sounds beautiful, with a dark background, and immense imaging.  I really wanted to capture a well balanced frequency response, which in itself has proven to be no easy challenge.  A very well known and highly regarded $2K+USD name-brand solid state preamp was used as a reference point for my tests.  I could have easily based my testing against another tube preamp, but I felt this preamp needed to have a very fast slew rate to have the modern characteristics I was after.  That said, this preamp is incredibly fast and articulate for a tube preamp.  It has the big body and musical tone of a tube pre, with an incredibly fast slew rate that comes close to solid state's ultra fast response.  I wanted this fast characteristic so the preamp could effectively be used on drums without sounding too mushy or vintage.  It was no easy task to achieve this, which is why I went through so many different preamp designs before reaching this one.

A lot of work is still needed to completely iron out the design, but when complete this will be an all inclusive dual channel preamp solution.  Input and output volume controls, front panel DI inputs, analog VU meters, phantom power, switches for low cut, phase reversal, mic/line inputs, and probably the variable & bypass-able treble roll off control from the 1401 stereo mic preamp.  I hope to be able to offer this hand-wired wonder for around $3,000 USD when complete.  The target release date is December 21st, 2015, but that is not yet set in stone, nor is the price.  Name suggestions for this dual channel tube preamp are now being accepted.  If you suggest a name that I end up using, I'll offer you a special discounted price and dibs on the first production model if you want.   

This past Thursday I shipped a Flux Bender out to Mix Engineer, Ronan Chris Murphy, who will be reviewing the Flux Bender on his youtube channel, Recording Boot Camp.   If you haven't read the May issue of Recording Magazine, the review on page 58 is a worthwhile read.  Paul Vnuk Jr. was quite impressed by the Flux Bender and I'm sure Ronan will not be let down. The Flux Bender is a very serious piece of equipment.  Keep a lookout in the future for Ronan's review of the Flux Bender! 

Some may know from previous posts that I have been developing a new equalizer, called the Arque Equalizer.  This is a mono, passive EQ with a crazy ton of controls and it will be introduced to the market at a very low price point.  About 2 days ago I finally completed the first prototype after a great deal of real world use in the studio and many modifications to the design.  Next on the road to production is a second prototype, which looks more like what the final product will look like.  This next prototype is more for the front panel layout design than anything else.  I plan to have the product ready for release before the year is out.  

Simultaneously I've also been developing a new dual channel mic preamp.  I started with the 1401 preamp and began making changes to it.  It was originally intended to be Rev. B for the 1401, but its now so radically different I can't justify giving it the 1401 label.  The new preamp offers 2x as much gain as the 1401, while amazingly exhibiting a lower noise floor.  It has VU meters for both channels, front panel DI inputs (which sound incredible, BTW), and maintains the 1401 treble cut filter circuit and gain control.  The preamp currently has a slight deficiency in treble which I'm currently working to iron out.  After that's complete, the next phase is adding on phantom power, a low cut switch, and line input switches.  There's still a lot of work to do before its ready for production, but as with the Arque Equalizer, I'm aiming to have this product complete by years end.

The mighty Flux Bender goes on its second bender today.  This afternoon I'll be shipping off a Flux Bender to world renown Mix Engineer, Ronan Chris Murphy for his professional review of the EQ.  Keep an eye out on his youtube channel for that review in the coming months!  

It may not seem obvious that I'm constantly designing and building new gear unless you have the inside scoop.  FWIW, that inside scoop is pretty simple to acquire if you follow along to my alternate blog at www.lbastudios.com.   LBA Studios is the place where new Lightning Boy ideas are developed.  There's a vast array of one-offs at LBA Studios that get pretty regular use at the studio, but will probably never see the light of production due to their over complexity or other factors.  There are a few things that exist as prototypes that will certainly be future LBA products.  Of those marvelous trinkets is an upcoming EQ, but there's something even bigger coming very soon and I promise not to spill the beans.  This one's going to be very special :)

Available today only.  There will be just 10 pedals made (first 2 already sold). Each of the LE Opti-Mu Prime pedals will have a new feature... an LED that indicates how much compression is going on.  The LED will be off if no compression is occurring and will glow brighter with more compression.  To further differentiate the LE Opti-Mu Prime from the original version, the LE version will be painted black.  

Now, to make things more interesting... if all 10 Opti-Mu Prime pedals sell today it'll convince me there's enough reason for me to consider building pedals again.  If I do decide to build pedals again I will not build any of the previous designs, such as Soul Drive, The Lightning Boy, Opti-Mu Prime, Bolt Bender, Olympus, etc.  I have something very special in mind instead, but lets first see how things go today.  Stay tuned on Facebook or Twitter for updates :)

Back from the grave!  The much revered, Opti-Mu Prime compressor pedal is back for just one day only.  Its a very limited edition run of just 10 pedals.  First come first serve.  Only 1 per customer.  I put building pedals to the side back in March, but there has been a significant number of people asking if I would build this pedal again.  Well, if you missed out before hopefully you won't miss out this time!  Hurry while they last:  http://www.lightningboyaudio.com/opti-mu-prime.html