Is this schematic enough for me to make a layout from?
I've been looking at the gear settings used to create the scooped heavy guitar tone on a certain album, and they mentioned using a Mesa Mk. IIc with the 5-band EQ set in a V, and then two Aphex EQs in the effects loop.
No problem, I thought, I can make some gyrator circuits and do all that from there. But, looking more closely, some of those EQs are shelving rather than parametric. So I googled the EQ in question and the first thing that came up was a PDF from the manufacturer's website, complete with what seems to be a full schematic of each section.
Am I missing something here, or is there enough for me to build a circuit from and build a PCB for? Pot tapers are the only thing I can think of, and I'll very likely omit the transformer on the output. These things still sell for £500 apiece on Reverb.com, so that might be quite a good thing to be able to replicate.
Re: Is this schematic enough for me to make a layout from?
There is missing info that you would need to know how to fill in. Most of these types of EQs are made with custom multi gang pots or switches. Audiomaintenencelimited has the best selection I’ve seen for these hard to find pots.
Transformers are a big deal in these vintage pro audio units. So if you’re trying to make a clone and you remove the output transformer you kinda just made a big change. That particular transformer is easy to find on eBay at a good price
Overall in my experience this just ain’t gonna happen for you and if it were to happen, £500 for the original is a GREAT alternative. But if you are really dedicated to this project and put in all the time, effort, and money necessary than anything is possible. Groupdiy would be an excellent resource for this project but avoid asking them to figure the whole thing out for you. There are many existing EQ projects over there which would be much more easily doable