Read this article first.
Summary:
“After using the two power conditioners with different components (both tube and solid state) and at different times of day and night, I reached the conclusion that the “DIY Hydra” was a sonic twin to the production Shunyata Hydra 4, taking into account the additional purity provided by eliminating the varistor in my “DIY Hydra”. I found that similar performance to a $700 manufactured product could be obtained for an expense of roughly $100 and some time and effort. The downside is that the “DIY Hydra” has a resale value of effectively zero. The well-reviewed – and deservedly so – Shunyata Hydra 4 will retain its value far better.”
Notes:
- New Hydra Model-4 costs between $800 and $1300.
- 2nd hand one can be found for $500-600
Conclusion:
- Do not buy new
- The DIY one costs less than the difference between “new” and “old”
Something to think about …