Join Date: Oct 2007
Location: Hill country, Texas
Russellc: Good that you are taking the plunge!!
The original stand mounted Manzanita using the GRS-15 has a calculated efficiency of around 84.5 DB/W. The larger Ultra is about 86.5 dbw. These efficiency ratings are good into the mid 40's on the Manzanita and lower 30's on the Ultra. The above frequencies are where the speakers BEGIN an initial 6db / octave roll off.
Your First Watt clones will be ideal for either speaker. If you build the Ultra, you will likely hear and feel bass you never knew was there and you will be able to recognize what instrument was used to create it! My point being the above efficiencies are real throughout the spectrum with none of the "harmonic doubling" so common in box speakers. Many box speakers start rolling off in the upper 50's to lower 70's area while claiming to be 88-90 DB/W! By the time they get into the lower 40's, they are more like 81-83 DB/W efficient. Enjoy!!
Commercial Website: https://manzanita-audio.com/