OK, no problem. So unregulated you have +/- 22 V ( still no value of the transformer though ) under load. LM7818/7918 can be used then if they only need to feed the 2 or 4 opamps of the filter.
They need around 3 V over them to function properly so only 1 V is left for ripple etc. Make sure the caps directly after the diode-bridge are big enough. Although 2 x 1000 uF/35 V will do 2 x 2200 uF/35 V might be a more audiophilic approach. Mmm, 4 x 1000 uF/35 V is even more audiophilic 😀 for what its worth.
If the supply feeds more circuits LM7815/7915 is a better choice as higher ripple will give too tight values for using LM7818/7918.
They need around 3 V over them to function properly so only 1 V is left for ripple etc. Make sure the caps directly after the diode-bridge are big enough. Although 2 x 1000 uF/35 V will do 2 x 2200 uF/35 V might be a more audiophilic approach. Mmm, 4 x 1000 uF/35 V is even more audiophilic 😀 for what its worth.
If the supply feeds more circuits LM7815/7915 is a better choice as higher ripple will give too tight values for using LM7818/7918.