Really Dylan (Roci)? Yep Okay Gents so I have good amount finished and it's time to make a choice and I'd love your opinion. I wanted to recreate the Helios modules just like as if they were pulled from the console but with a modern twist (and some god damn Cinemag output transformers cause they sound bad ass) Original Helios modules went unbalanced. All i have done was used a modern take based on the Helios summing amp (an idea Ian from Ruff Records's once suggested) and then put an appropriate transformer on the end.
So what do you think; should I lay it out as a half-rack like Warm Audio's wa12 or Great River's ME-2NV or stand it up-right as if it was a module pulled out of the console? Here's a rough idea which is missing the knobs and switches.
There's a somewhat external psu via a wall wart or small enclosure (not sure which yet). And of course some touch ups here and there (I forgot the 'gain dB" text on the up-right version for instance). One or two of the switches will also be illuminated push button. You know.... like modern.
Sorry gents forgot to put on notifications. Okay so first off; if it was vertical it would not be rack mountable so i imagine a desktop piece. I am gonna possibly make a 500 series version down the line but i wanted something that could be under its own power and that looked like an actual module. The amp circuit is virtually identical minus modern transistor replacements, the filter section is Ian's of Ruff Records, and the final stage is nearly the same the helios summing section with a few added components. I think the output transformer makes it better and so it would be safer to say this is based on the Helios 69. It will be probably powered by wall wart.
I am not a designer. I will not pretend to be, but its an easy enough circuit to implement and so i cant go too wrong. Plus ive had a ton of help. That all said i plan on doing every test possible.
Price isn't determined yet. I'm putting these through the paces though and am going to bring them somewhere for measurements and testing. I want to stand behind what these do without inflating figures or whatnot. Helios was never some perfect noiseless amp with a giant headroom so i dont expect these to be impeccable. That said i just recorded an acoustic the other day with my other helios and it sounds great. I also have kept a helios 69 eq on one of my guitar mixing channels as it superbly pulls guitars out of the mix. I often alternate between a helios into an 1176 rev a or j and the 1084 into a wa76 for my lead and rhythm guitars.
Whew... Other than the gain switch being a little finicky she is noiseless and acting alright. I got a ton of tests i have to do so I'm not prepared to pop open the champagne just yet but its nearing the end. And then i begin the next one. Its currently sharing a psu so I'll have to build one that can power eight. Eventually this will go to this mixing/mastering engineer friend of mine to add to his already beautiful collection.
Last Edit: Jul 10, 2017 23:02:16 GMT -6 by rocinante
A few noteworthy things: I should have made the pcbs smaller but at the time I didn't really think I was going to be doing more than 1 or 2. So far Ive made and sold 3 of the 1u full size mic pre/eqs. Honestly I just wanted to get it right and so used a larger platform. I should have put a 10K trimmer on for the pcbs. Maybe I will the next batch. I would have liked to have met Dick Swettenham. David from Cinemag has been super helpful. I can't say the same for the current helios associated guys (which is neither here or there they dont have to help me) although Cyril Jones has been alright. Ian Thompson Bell, Jeff Steiger, Tiago, PRR, Pastah, also helped a ton.
Post by ruffrecords on Jul 22, 2017 1:42:44 GMT -6
Very nice build!! When you are done, could you send me a some good quality pics so I can include it in the gallery of DIY projects incorporating my designs? Pierre at groupDIY hosts this at the moment but I am thinking of adding a Gallery tab to my web site.