diff --git a/libavcodec/aacenc_utils.h b/libavcodec/aacenc_utils.h
index cb5bc8da12..c2a2c2ec68 100644
--- a/libavcodec/aacenc_utils.h
+++ b/libavcodec/aacenc_utils.h
@@ -90,8 +90,7 @@ static inline float find_max_val(int group_len, int swb_size, const float *scale
 
 static inline int find_min_book(float maxval, int sf)
 {
-    float Q = ff_aac_pow2sf_tab[POW_SF2_ZERO - sf + SCALE_ONE_POS - SCALE_DIV_512];
-    float Q34 = sqrtf(Q * sqrtf(Q));
+    float Q34 = ff_aac_pow34sf_tab[POW_SF2_ZERO - sf + SCALE_ONE_POS - SCALE_DIV_512];
     int qmaxval, cb;
     qmaxval = maxval * Q34 + C_QUANT;
     if (qmaxval >= (FF_ARRAY_ELEMS(aac_maxval_cb)))