suboctave

suboctave

(sʌbˈɒktɪv)
n
an octave below another octave
References in periodicals archive ?
In contrast, switched preselection filters typically have fixed suboctave ranges, and a number of them are needed to cover a large frequency range.
My only reservations concern the use of a violone at suboctave pitch, which to my ears unbalances the texture; the use of harp and harpsichord together (occasionally) as continuo, and especially as soloists in the Allemande; and the intrusive and unnecessary (if intermittent) use of percussion.
These are easily attenuated by choosing the preselector filters to be suboctave (for example 2.0-3.0 GHz, 2.5-4.0 GHz, etc.).
In this case, the coupling efficiency is closer to 40 to 50 percent, and the RF loss is reduced to < 30 dB + 0.16T Finally, transformative or reactive matching can further reduce the loss over suboctave bandwidths.