diff --git a/libavcodec/aaccoder.c b/libavcodec/aaccoder.c
index 994de28..f432a22 100644
--- a/libavcodec/aaccoder.c
+++ b/libavcodec/aaccoder.c
@@ -710,7 +710,7 @@ static void search_for_quantizers_twoloop(AVCodecContext *avctx,
                                           const float lambda)
 {
     int start = 0, i, w, w2, g;
-    int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate / avctx->channels;
+    int destbits = avctx->bit_rate * 1024.0 / avctx->sample_rate / avctx->channels * (lambda / 120.f);
     float dists[128] = { 0 }, uplims[128];
     float maxvals[128];
     int fflag, minscaler;
@@ -1021,29 +1021,27 @@ static void search_for_quantizers_fast(AVCodecContext *avctx, AACEncContext *s,
                                        SingleChannelElement *sce,
                                        const float lambda)
 {
-    int i, w, w2, g;
-    int minq = 255;
+    int w, w2, g;
+    float lowlambda = av_clip(120.f / lambda, 0.25f, 1.f);
+    float rlambda = av_clip(120.f / lambda, 0.3f, 2.f);
+    const int minq = av_clip(2 * log2f(120.f / lambda) + 150, 100, 218 - SCALE_MAX_DIFF);
+    const int maxq = minq + SCALE_MAX_DIFF - 1;
 
     memset(sce->sf_idx, 0, sizeof(sce->sf_idx));
     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w]) {
         for (g = 0; g < sce->ics.num_swb; g++) {
             for (w2 = 0; w2 < sce->ics.group_len[w]; w2++) {
                 FFPsyBand *band = &s->psy.ch[s->cur_channel].psy_bands[(w+w2)*16+g];
-                if (band->energy <= band->threshold) {
-                    sce->sf_idx[(w+w2)*16+g] = 218;
+                if (band->energy <= 0.05 * lowlambda * band->threshold) {
+                    sce->sf_idx[(w+w2)*16+g] = maxq;
                     sce->zeroes[(w+w2)*16+g] = 1;
                 } else {
-                    sce->sf_idx[(w+w2)*16+g] = av_clip(SCALE_ONE_POS - SCALE_DIV_512 + log2f(band->threshold), 80, 218);
+                    sce->sf_idx[(w+w2)*16+g] = av_clip(SCALE_ONE_POS - SCALE_DIV_512 + log2f(band->threshold * rlambda), minq, maxq);
                     sce->zeroes[(w+w2)*16+g] = 0;
                 }
-                minq = FFMIN(minq, sce->sf_idx[(w+w2)*16+g]);
             }
         }
     }
-    for (i = 0; i < 128; i++) {
-        sce->sf_idx[i] = 140;
-        //av_clip(sce->sf_idx[i], minq, minq + SCALE_MAX_DIFF - 1);
-    }
     //set the same quantizers inside window groups
     for (w = 0; w < sce->ics.num_windows; w += sce->ics.group_len[w])
         for (g = 0;  g < sce->ics.num_swb; g++)
diff --git a/libavcodec/aacpsy.c b/libavcodec/aacpsy.c
index b3513c7..1fa59c8 100644
--- a/libavcodec/aacpsy.c
+++ b/libavcodec/aacpsy.c
@@ -316,7 +316,7 @@ static av_cold int psy_3gpp_init(FFPsyContext *ctx) {
         AacPsyCoeffs *coeffs = pctx->psy_coef[j];
         const uint8_t *band_sizes = ctx->bands[j];
         float line_to_frequency = ctx->avctx->sample_rate / (j ? 256.f : 2048.0f);
-        float avg_chan_bits = chan_bitrate / ctx->avctx->sample_rate * (j ? 128.0f : 1024.0f);
+        float avg_chan_bits = chan_bitrate * (j ? 128.0f : 1024.0f) / ctx->avctx->sample_rate;
         /* reference encoder uses 2.4% here instead of 60% like the spec says */
         float bark_pe = 0.024f * PSY_3GPP_BITS_TO_PE(avg_chan_bits) / num_bark;
         float en_spread_low = j ? PSY_3GPP_EN_SPREAD_LOW_S : PSY_3GPP_EN_SPREAD_LOW_L;