I’d like to make my own RIAA all tube pre but they are freaking expensive. Was interested in the Mars Preamp but it’s out of my price range. Can anyone direct me here? The reply should preferably come from someone that has built the pre and uses it because it is good. Looking at not more than R2 000.00. Audio Technica TT with MC.
Hello Roggie and welcome to this forum!
Just moderated your post. Please let the readers know whether high output MC or low? The AT turntables I have come across were all sold with MM. If it is high output MC the Yaqin MS23B or 22B may be what you are looking for. In the USA they go for about $200 and is “middle” to “very good” according to ratings. I have only heard this with Mullard tubes, guy in CPT’s Blouberg. Was very good to my ears.
Let us know and let’s see what comes up. I have a few circuits which I have tried but nothing currently on the bench.
Welcome to the club!
I built the Bottlehead Foreplay when it first came out. I learnt a few things from this exercise and I am not criticising the amp. In South Africa you will be pressed to make things cheaper because $$$ also means shipping $$$. You can easily build a quality tube preamplifier for under R2K. Experimentation is always half the fun. 99% of my projects get shelved after a month of playing around with it because I do believe if it looks like “k*k” it’s gonna sound like “k*k”. I don’t want to embarrass myself in front of friends and family although they cannot do what I do.
Get yourself a couple of ECC83s, they are not expensive. I can’t suggest which make to get (I usually have good results with NOS Mullards), do some reading. Use two 220:12 transformers back to back to get your EHT and heater voltage. DC and regulate your heater voltage through a LM317. Use good quality components. If this is one to give you a lasting impression get a Hammond aluminium case. You may be able to build the whole lot for about R1400.00. Here’s the Marantz 7 RIAA schematic.
You know what, play with it and learn as you go along. The most important aspect to any sensitive preamplifier is always shielding, transformer hum and heater supply layout. In time you may find a battery suppplied INA217 preamp will cost thirty times less and sound better 🙂
Have a take here – I think you may be in for a surprise.
And as always, take care and have fun…