diff --git a/src/filters.h b/src/filters.h
index 454a12a..ca3b43a 100644
--- a/src/filters.h
+++ b/src/filters.h
@@ -132,11 +132,11 @@ static inline float high_cut_iir(int i, float NewSample) {
 
 
 #undef NCoef
-#define NCoef 1
+#define NCoef 2
 
 //fc=3.2kHz
 static inline float sb_iir(int i, float NewSample) {
-/*    float ACoef[NCoef+1] = {
+    float ACoef[NCoef+1] = {
         0.03356837051492005100,
         0.06713674102984010200,
         0.03356837051492005100
@@ -146,9 +146,9 @@ static inline float sb_iir(int i, float NewSample) {
         1.00000000000000000000,
         -1.41898265221812010000,
         0.55326988968868285000
-    };*/
+    };
     
-    float ACoef[NCoef+1] = {
+/*    float ACoef[NCoef+1] = {
         0.17529642630084405000,
         0.17529642630084405000
     };
@@ -156,7 +156,7 @@ static inline float sb_iir(int i, float NewSample) {
     float BCoef[NCoef+1] = {
         1.00000000000000000000,
         -0.64940759319751051000
-    };
+    };*/
     static float y[2][NCoef+1]; //output samples
     static float x[2][NCoef+1]; //input samples
     int n;
diff --git a/src/sound_opl.c b/src/sound_opl.c
index 0ec7643..9fece84 100644
--- a/src/sound_opl.c
+++ b/src/sound_opl.c
@@ -83,8 +83,8 @@ void opl2_update2(opl_t *opl)
                 opl2_update(1, &opl->buffer[opl->pos*2 + 1], sound_pos_global - opl->pos);
                 for (; opl->pos < sound_pos_global; opl->pos++)
                 {
-                        opl->filtbuf[0] = opl->buffer[opl->pos*2]   = (opl->buffer[opl->pos*2]   / 4) + ((opl->filtbuf[0] * 11) / 16);
-                        opl->filtbuf[1] = opl->buffer[opl->pos*2+1] = (opl->buffer[opl->pos*2+1] / 4) + ((opl->filtbuf[1] * 11) / 16);
+                        opl->filtbuf[0] = opl->buffer[opl->pos*2]   = (opl->buffer[opl->pos*2]   / 2);
+                        opl->filtbuf[1] = opl->buffer[opl->pos*2+1] = (opl->buffer[opl->pos*2+1] / 2);
                 }
         }
 }
@@ -96,8 +96,8 @@ void opl3_update2(opl_t *opl)
                 opl3_update(0, &opl->buffer[opl->pos*2], sound_pos_global - opl->pos);
                 for (; opl->pos < sound_pos_global; opl->pos++)
                 {
-                        opl->filtbuf[0] = opl->buffer[opl->pos*2]   = (opl->buffer[opl->pos*2]   / 4) + ((opl->filtbuf[0] * 11) / 16);
-                        opl->filtbuf[1] = opl->buffer[opl->pos*2+1] = (opl->buffer[opl->pos*2+1] / 4) + ((opl->filtbuf[1] * 11) / 16);
+                        opl->filtbuf[0] = opl->buffer[opl->pos*2]   = (opl->buffer[opl->pos*2]   / 2);
+                        opl->filtbuf[1] = opl->buffer[opl->pos*2+1] = (opl->buffer[opl->pos*2+1] / 2);
                 }
         }
 }
diff --git a/src/sound_sb.c b/src/sound_sb.c
index d4212ca..6c699bc 100644
--- a/src/sound_sb.c
+++ b/src/sound_sb.c
@@ -43,9 +43,9 @@ typedef struct sb_t
 
 static int sb_att[]=
 {
-        310,368,437,520,618,735,873,1038,1234,1467,1743,2072,2463,2927,3479,
-        4134,4914,5840,6941,8250,9805,11653,13850,16461,19564,23252,27635,32845,
-        39036,46395,55140,65535
+        50,65,82,103,130,164,207,260,328,413,520,655,825,1038,1307,
+        1645,2072,2608,3283,4134,5205,6553,8250,10385,13075,16461,20724,26089,
+        32845,41349,52055,65535
 };
 
 static void sb_get_buffer_opl2(int32_t *buffer, int len, void *p)
@@ -61,8 +61,8 @@ static void sb_get_buffer_opl2(int32_t *buffer, int len, void *p)
         {
                 int32_t out_l, out_r;
                 
-                out_l = ((sb->opl.buffer[c]     * mixer->fm_l) >> 16);
-                out_r = ((sb->opl.buffer[c + 1] * mixer->fm_r) >> 16);
+                out_l = ((((sb->opl.buffer[c]     * mixer->fm_l) >> 16) * 55000) >> 16);
+                out_r = ((((sb->opl.buffer[c + 1] * mixer->fm_r) >> 16) * 55000) >> 16);
 
                 if (sb->mixer.filter)
                 {
@@ -112,8 +112,8 @@ static void sb_get_buffer_opl3(int32_t *buffer, int len, void *p)
         {
                 int32_t out_l, out_r;
                 
-                out_l = ((sb->opl.buffer[c]     * mixer->fm_l) >> 16);
-                out_r = ((sb->opl.buffer[c + 1] * mixer->fm_r) >> 16);
+                out_l = ((((sb->opl.buffer[c]     * mixer->fm_l) >> 16) * 55000) >> 16);
+                out_r = ((((sb->opl.buffer[c + 1] * mixer->fm_r) >> 16) * 55000) >> 16);
 
                 if (sb->mixer.filter)
                 {