Spectrum +2 Crisp Stereo Sound Mod

The Sinclair Spectrum is a computer that I never played or even saw in person back in the day. It was never sold in retail chain in Australia, so was only stocked by very few specialty stores. I read about games for the Spectrum in C+VG magazine, and was content that The Commodore 64 was a much better micro for me. As a collector of all things computer and gaming related, the Spectrum did start to appeal to me with its particular graphical style when done well, and some versions of games were better than the C64 counterparts (only sometimes!). Fast forward to 2016 I bought a 48k rubber key Spectrum, and in 2017 found a local Spectrum +2 (Grey model).

Recently I picked up the fabulous Div MMC Future from TFW8B.com for ease of loading games with modern media. The good thing about some Spectrum models including the +2 is that they have RGB out for a great crisp output. Once I got a SCART cable I had glorious RGB. BUT the audio output was terrible! The sound was very muffled, with fuzzy noise. After some quick searching I discovered this was a common problem. There were also details about some components (capacitors & resistors) in Spectrums that were installed incorrectly, or with incorrect values that may cause the issue. I was about to prepare to fix some of these issues when I came across a Crisp Stereo Sound Mod for any 128k Spectrum from ByteDelight. This audio improvement kit had really positive reviews, so I decided to give it a go. I am very happy to say it makes an enormous improvement to the audio output, and even sounds better than I expected. It is very easy to install if you have basic soldering skills, and I share a pictures and details below:

Here is the kit. Installation between different models is a bit different, with some models requiring modifications to tracks and components. Luckily for me the Grey +2 model is the simplest to install. This is all detailed in the easy to follow instructions.
Here it is, the ZX Spectrum +2 for installing the mod. Crisp audio is coming!
Remove all the screws from underneath, then carefully remover the top cover, being mindful of the 2 ribbon connectors on the left and tape drive plug on the centre right which need to be disconnected.
The chip marked AY-3-8912A is where the mod board will be placed.
There are a couple of wires that need to be connected to the pins of the ULA chip, which has a heatsink in the Grey +2 model.
Mode board and ULA connections now soldered in place. Very easy to install, with simple to follow instructions.
Last thing to do is drill a new hole in the case for the new stereo audio socket. In the Grey +2 model, this can fit on the very right hand side, next to the existing audio socket.

Once everything is back together, the last thing you need is a cable capable of handling your new Spectrum stereo audio. There may be sellers who sell cables ready made for stereo. However I pulled part my existing SCART cable and modified it to work with stereo.

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