AKLIAM's discrete op-amp, the LC5, is a set of 2. I purchased these in June of this year and used them for about 30 hours. You may be able to improve the sound quality by replacing your existing dual op-amps with these. This is a specialized product, so purchase is recommended for those with a certain level of knowledge. I have a pet-free and smoke-free environment. Please understand that this is a used item before purchasing. Thank you for looking.