A-Designs Audio EM-PEQ Pultec-style equalizer

Discussion in 'Graphic / Parametric EQ' started by audiokid, May 9, 2012.

  1. audiokid

    audiokid Staff

    Anyone use the A-Designs Audio EM-PEQ? I'm looking to add a Pultec style to my hybrid chain. How quiet is this and what's your opinion?
     
  2. pan60

    pan60 Active Member

    i have a couple here and they rank in the top of my list of EQs i love love love!
    when you say noise what are you asking?
    you can most likely find the speck on the A-Designs web site. i have not had any issues with noise at all.
    no reason for anything 500 format to be any noisier than any other format.
     
  3. Jon Erickson

    Jon Erickson Active Member

    Hey folks. Jon Erickson here. I designed this unit along with Peter Montessi. I like to think that we successfully maintained the core vibe and functionality of the vintage eqs we were inspired by, while making it more friendly to the modern studio. Some examples are: Well matched channels, very low noise, high input/low output impedances per modern standards versus the 600 ohm telephone company standard and the ability to handle more signal(especially bass) without excess distortion. I personally spent many years working with vintage gear and it continues to be a passion of mine, but we are working in the digital world now and many of the rules that worked 30, 40, 50 years ago need a bit of tweaking. Feel free to hit me with any questions.

    Jon Erickson
     
  4. audiokid

    audiokid Staff

    Hi Jon, what a nice surprise, welcome to our community! I have the Nail and love it so the obvious move is towards more A-Design. I have a few questions for sure. I'm the first to admit I'm not very educated with the technical aspects of engineering so every once in a while I ask a pretty newbie question.

    Please explain:
    Here is one good one! If you feel comfortable engaging in, please do.

    Reading endless topics on forums on how DAW's are so clean and plug-ins sound better than hardware, I finally had to invest in a hybrid system a few years back to see what it was all about. Until I completed a properly designed hybrid system (which I think needs to be mentioned here), I could not have know the true benefits of what I know now. Hybrid is the best of both world, applying variety where it counts the most. Using hardware in the right spots with a digital mix definitely spreads the sound out, thus, givs a generic ITB sound much more unique flavor to say the least. This is of course a big topic but that's a quick peek into it. Hybrid is the best of both worlds so, I'm now 100% focused on supporting companies like A-Design more than I have ever been with recording.org. Please pass that on.

    How I got to this: I'm a musician that got into this business 30 years ago because I wanted to record my music. I've gone from analog to 100 ITB to now hybrid. I'm finding less and less interest and need for plug-ins and putting more detail towards hardware on the 2-bus, well, more than that but I'll stop by saying this: I think hybrid is discovering the balance between OTB and OTB.

    I would love to hear your opinions on hardware vs software in this DAW age? When people talk about plug-ins, how do you describe the sound difference between hardware and software. How do you see A-Design / pro audio evolving in the digital domain?

    Cheers!
     
  5. pan60

    pan60 Active Member

    thanks for post Jon.
    Jon is the man that will know for sure: )
    the bass on these is amazing!
     
  6. Jon Erickson

    Jon Erickson Active Member

    Thanks for the warm welcome! Its a pleasure to be here.

    "high input/low output impedances per modern standards versus the 600 ohm telephone company standard"
    "the ability to handle more signal(especially bass) without excess distortion"


    There are endless explanations about this online and I'm probably not the best person to explain it but let me take a swing. Many of you may already know this, but the Pultec EQP series was designed by Western Electric for the telephone company to adjust the equalization of long transmission phone lines. Recording studio use was third in line after broadcast. There was a standard based on a a theory of "maximum power" where input and output impedances we're "matched". This maximized the signal transmission and minimized reflections which could manifest as actual echoes on the phone line. 600 ohm input and 600 ohm output was the standard. I'm just touching on the subject. Theres an excellent Sound on Sound article by Hugh Robjohns that goes into great detail on this topic and impedance in general here.

    Today the vast majority of modern audio equipment is designed to a different approach called "impedance bridging". EG. A lower impedance "source" such as a microphone at 150 ohms feeds a mic pre with a much higher 1500 ohm input impedance or "load". A compressor's line output of 100 ohms feeds a 10,000 ohm line input. These are common ratios. Some people say 1:5 is a minimum ratio, others say 1:10 and some put it much higher with certain relationships such as a passive bass pickup and a direct box. This method maximizes the transfer of voltage, frequency response and overall signal integrity. When we start playing around with lower ratios, say feeding a 5kohm guitar pickup into a 10kohm line input we quickly see the degradation of frequency response and signal quality. If there's any basic math to get under your belt as an engineer I'd say that this is it.

    I'm not saying that a vintage Pultec sounds like crap because it is 600 ohms! They are magical units with a ton of vibe and the 600 ohm thing is part of that mojo, but they don't always play nice with the other gear around it looking for a much higher load or lower source. When we designed the EM-PEQ and EM-EQ2 we utilized a high input impedance and low output impedance so you could drive this box with just about anything into anything. We're flattered that there's a lot people using this for mastering and 2-bus processing and in hopes of this made signal integrity a top priority in the design. We use a Cinemag hi-nickel core transformer which translates into super wide frequency response that can handle big bass with very clear highs. This is also a difference from the vintage units, whose transformers had higher levels of harmonic distortion. Today we're dealing with 6 string bass and 808 kick drums that like to munch your low end. Bass is always a high priority at A-Designs.

    Plugins verus hardware? I have no beef against plugins and there are some things that blow me away. I love a good EMT 140 but some of those convolution reverbs are incredible. When it comes to eqs and compressors I'm still very much in the analog camp on sonics and ergonomics. To my ear its much more than just a few percent sonic difference and being able to put two hands on a piece of gear and jockey the knobs at the same time is no small detail. At this point I think that theres a big swing back to analog equipment. Black Keys, Dave Grohl, Jack White, Daptone... Crazy as it sounds but there are a ton of younger engineers that want to hold some steel in their hands and are kinda sick of computers. I just bought an Ampex 600 tube 1/4" full track on Ebay if that tells you anything about my sensibility. Like the Ampex I just want to design things that I'll be able to use in 30 years and that keeps me huffing solder.

    Will A-Designs enter the plugin arena? Hard to say. I sure wish I'd studied computer science some days, but for now we're very happy doing what we're doing.

    Jon Erickson
     
  7. audiokid

    audiokid Staff

    Hey, thanks for taking the time to post this Jon!

    We're hearing good things about Cinemag transformer. I have a feeling it may be stemming from your work with A-Designs. I think you've nailed what the next generation is real thirsty for! Big bass with very clear highs is what A-Designs is becoming well known for! And you are clearly finding the balance between vintage and today's hybrid systems. When I research gear, I want to hear exactly what you are talking about. Right on.

    Please feel welcome to talk about all sorts of stuff here. We need more of that and less plug-in chat IMHO.
     
  8. Jon Erickson

    Jon Erickson Active Member

    Yes the folks at Cinemag make what we believe to be the best available transformer here in the US. They are right down the road from us so we get to have a lot of face to face interaction in product development.

    Feels good these days to be an old fashioned type US manufacturer. I'm as addicted as the next guy to my iphone, but Im sure glad to be making things out of steel for a living!

    Jon Erickson
     
  9. audiokid

    audiokid Staff

    Hey Jon, that's really good to hear.

    If I could be so forward to ask for more detail on the Cinemag trannies, and I think others would be interested to learn more too: Are they a step up from say a Lundahl or Jensen or just more refined to your specs, which in turn produce's the choice combination that gives you your sound? In layman's terms, what are they doing different or how do they help the tight bass you are getting with A-Designs gear?

    Interesting, are you referring to bass boost? or, just a more smooth curve needed to keep everything audible?
     
  10. Jon Erickson

    Jon Erickson Active Member

    The telephone engineers strove to keep the frequency response flat from the point of transmission to its end point. As you could imagine there was likely some high frequency loss which the boost control/bandwidth controls were used to correct. I imagine that 10k and 12k were often used. There must have been cases of low frequency boominess which the low attenuate would help correct. I've always wondered if they found a use for the simultaneous low boost/atten trick that works so well in the studio.

    Back to the transformer question. Ive used Lundahls and Jensens in the past and they make outstanding transformers. We simply find the Cinemag units to be of comparable or higher quality and working locally gives us a big leg up. We like to have eyes on every step of manufacturing and working with your neighbors is the ideal. In terms of the great bass the transformers definitely help. They have very wide frequency response and high level handling ability blended with just a touch of harmonic distortion. Ultimately though, Peter and I are both bass players and many of our core clients and beta testers are bassists as well. We simply listen with bass player ears in the design process and that informs many of our decisions.

    Jon Erickson
     

Share This Page