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*Soundgas Type 636P (Grampian Preamp) - Deposit to Reserve

*Soundgas Type 636P (Grampian Preamp) - Deposit to Reserve

Brand: Soundgas

Regular price £500.00 GBP | Inc.VAT: £600.00 GBP
Regular price Sale price £500.00 GBP
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Exports are EX-VAT worldwide. VAT Included at checkout for UK Customers.

Payment Options

Next build June 2024: Pre-order now! Pay in full £1295 + VAT or you can elect to pay £500+ VAT now and the balance when your 636P is ready.

Desktop version of our Grampian 636 mic preamp circuit: no corners cut, all the ragged filthy glory of the Type 636 mic preamp in a handy portable unit.

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Product Description

Desktop version of our Soundgas Type 636: no corners cut, all the ragged filthy glory of the Grampian/Soundgas 636 mic preamp in a handy portable unit.

If you want a footswitch/guitar pedal version please see this listing.

What is it? This is the hairy circuit you find in the mic preamp section of the Soundgas Type 636 - based on the Grampian Type 636 - famously used and abused by Lee Scratch Perry and Pete Townshend - and many others since. This is designed and built absolutely in the spirit of the original vintage units - no surface mount components or tone sapping DSP. 

How is this version different to the Prototypes? Photos are of the latest version. Based on feedback and our own testing of the original units, we have moved the input and output sockets to the rear of the box and added a three position attenuation switch on the output. This to tame the massive amount of gain produced when dialling in maximum overdrive/filth: now you can have all the dirt without overloading your amp/ears/signal chain. We have kept the industrial/functional aesthetic of the prototypes with a raw casing and just the switch, light and knob on the top.

More information:

The unit features a balanced input via combined TRS/XLR socket, vintage germanium transistor circuitry with original Grampian specification Mic transformer, overload lamp, input impedance switch, output 3-way attenuator switch and on/off toggle switch. Staying true to the original Grampian 636 design, the output is unbalanced on a ¼” jack socket and is out of phase.

Power is via a 12v external supply (included)

As with our original 636s, we have put tonal considerations ahead of all else. I was skeptical that we’d see a real benefit in using germanium transistors in the buffer section: all our original prototypes had used silicon and sounded great. However Dr Huw insisted that we build an all germanium version for comparison which proceeded to blow all the earlier versions out of the water.

The current situation regarding component shortages means that while we have secured enough vintage components to build 100 units, getting essential modern components is proving trickier with long lead times, a great deal of uncertainty and a significant outlay required. We are taking these preorders to help secure further components and to help fund the early stages of the production process. 

There's more info on the build including photos and demos here.



Brand new item.

Voltage Information

See description for more information.


For sales in UK the price will include 20% VAT. Buyers elsewhere may incur VAT or other local taxes on import.