diff --git a/src/MusicProcessing.jl b/src/MusicProcessing.jl
index fe91bb4..87eb2ba 100644
--- a/src/MusicProcessing.jl
+++ b/src/MusicProcessing.jl
@@ -3,6 +3,7 @@ module MusicProcessing
 using DSP
 using FFTW
 using FixedPointNumbers
+using LinearAlgebra
 using Requires
 using Unitful
 using IntervalSets
diff --git a/src/TFR.jl b/src/TFR.jl
index 0ebaac5..6da7138 100644
--- a/src/TFR.jl
+++ b/src/TFR.jl
@@ -239,7 +239,7 @@ function phase_vocoder(stft::Array{Complex{T}, 2},
 
         # store to output array
         cis!(cis_phase, phase_acc)
-        multiply!(cis_phase, cis_phase, mag)
+        cis_phase .= cis_phase .* mag
         for i in 1:nbins
             stretched[i, t] = cis_phase[i]
         end
diff --git a/src/display.jl b/src/display.jl
index 049fbdd..872bc2d 100644
--- a/src/display.jl
+++ b/src/display.jl
@@ -1,3 +1,4 @@
+import Base.show
 
 # methods to translate
 
@@ -16,11 +17,11 @@ function yticklabels(tfr::MFCC, yticks::Array)
     map(Int, map(round, yticks)), "MFCC number"
 end
 
-heatmap(tfr::DSP.Periodograms.TFR) = log10(power(tfr))
+heatmap(tfr::DSP.Periodograms.TFR) = map(x -> log(10,x), tfr.power)
 
 function draw_heatmap(tfr::DSP.Periodograms.TFR)
-    X = time(tfr)
-    Y = freq(tfr)
+    X = tfr.time
+    Y = tfr.freq
     Z = heatmap(tfr)
 
     PyPlot.pcolormesh(X, Y, Z)
diff --git a/src/mel.jl b/src/mel.jl
index 196e146..0c06bc7 100644
--- a/src/mel.jl
+++ b/src/mel.jl
@@ -26,7 +26,7 @@ function hz_to_mel(frequencies::Union{F, AbstractArray{F}}) where {F <: Real}
     f_min = 0f0
     f_sp = 200f0 / 3
 
-    mels = collect((frequencies - f_min) / f_sp)
+    mels = collect((frequencies .- f_min) ./ f_sp)
 
     min_log_hz = 1000f0
     min_log_mel = (min_log_hz - f_min) / f_sp
@@ -45,7 +45,7 @@ end
 function mel_to_hz(mels::Union{F, AbstractArray{F}}) where {F <: Real}
     f_min = 0f0
     f_sp = 200f0 / 3
-    frequencies = collect(f_min + f_sp * mels)
+    frequencies = collect(f_min .+ f_sp .* mels)
 
     min_log_hz = 1000f0
     min_log_mel = (min_log_hz - f_min) / f_sp
@@ -65,39 +65,43 @@ function mel_frequencies(nmels::Int = 128, fmin::Real = 0.0f0, fmax::Real = 1102
     min_mel = hz_to_mel(fmin)[1]
     max_mel = hz_to_mel(fmax)[1]
 
-    mels = linspace(min_mel, max_mel, nmels)
+    mels = range(min_mel, max_mel, length=nmels)
     mel_to_hz(mels)
 end
 
 """"""
 function mel(samplerate::Real, nfft::Int, nmels::Int = 128, fmin::Real = 0f0, fmax::Real = samplerate/2f0)
-    weights = zeros(Float32, nmels, (nfft >> 1) + 1)
+    second_dim = ((nfft >> 1) + 1)
+    weights = zeros(Float32, nmels, second_dim)
     fftfreqs = fft_frequencies(samplerate, nfft)
     melfreqs = mel_frequencies(nmels + 2, fmin, fmax)
-    enorm = 2f0 ./ (melfreqs[3:end] - melfreqs[1:nmels])
+    enorm = 2f0 ./ (melfreqs[3:end] .- melfreqs[1:nmels])
 
     for i in 1:nmels
-        lower = (fftfreqs - melfreqs[i]) / (melfreqs[i+1] - melfreqs[i])
-        upper = (melfreqs[i+2] - fftfreqs) / (melfreqs[i+2] - melfreqs[i+1])
+        lower = (fftfreqs .- melfreqs[i]) ./ (melfreqs[i+1] .- melfreqs[i])
+        upper = (melfreqs[i+2] .- fftfreqs) ./ (melfreqs[i+2] .- melfreqs[i+1])
+
+        for j in 1:second_dim
+            weights[i, j] = max(0, min(lower[j], upper[j])) * enorm[i]
+        end
 
-        weights[i, :] = max(0, min(lower, upper)) * enorm[i]
     end
 
     weights
 end
 
 function melspectrogram(audio::SampleBuf{T, 1}, windowsize::Int = 1024, hopsize::Int = windowsize >> 2;
-                        nmels::Int = 128, fmin::Real = 0f0, fmax::Real = audio.samplerate.val / 2f0) where T
-    samplerate = audio.samplerate.val
+                        nmels::Int = 128, fmin::Real = 0f0, fmax::Real = audio.samplerate / 2f0) where T
+    samplerate = audio.samplerate
     nfft = DSP.nextfastfft(windowsize)
     S = spectrogram(audio, windowsize, hopsize).power
     data = mel(samplerate, nfft, nmels, fmin, fmax) * S
     nframes = size(data, 2)
-    MelSpectrogram(data, linspace(hz_to_mel(fmin)[1], hz_to_mel(fmax)[1], nmels), (0.0:nframes-1) * hopsize / samplerate)
+    MelSpectrogram(data, range(hz_to_mel(fmin)[1], hz_to_mel(fmax)[1], length=nmels), (0.0:nframes-1) * hopsize / samplerate)
 end
 
 function mfcc(audio::SampleBuf{T, 1}, windowsize::Int = 1024, hopsize::Int = windowsize >> 2;
-              nmfcc::Int = 20, nmels::Int = 128, fmin::Real = 0f0, fmax::Real = audio.samplerate.val / 2f0) where T
+              nmfcc::Int = 20, nmels::Int = 128, fmin::Real = 0f0, fmax::Real = audio.samplerate / 2f0) where T
     if nmfcc >= nmels
         error("number of mfcc components should be less than the number of mel frequency bins")
     end
diff --git a/src/util.jl b/src/util.jl
index 2d2cecd..9f8f324 100644
--- a/src/util.jl
+++ b/src/util.jl
@@ -3,7 +3,7 @@
 tofloat(array::AbstractArray{T}) where T = map(Float32, array)
 tofloat(array::AbstractArray{Float32}) = array
 
-fft_frequencies(samplerate::Real, nfft::Int) = collect(linspace(0f0, samplerate / 2f0, (nfft >> 1) + 1))
+fft_frequencies(samplerate::Real, nfft::Int) = collect(range(0f0, samplerate / 2f0, length=(nfft >> 1) + 1))
 
 
 """returns the number of frames when the signal is partitioned into overlapping frames"""
@@ -42,10 +42,12 @@ end
 
 """returns the DCT filters"""
 function dct(nfilters::Int, ninput::Int)
-    basis = Array(Float32, nfilters, ninput)
+    basis = Array{Float32}(undef, nfilters, ninput)
     samples = (1f0:2f0:2ninput) * π / 2ninput
     for i = 1:nfilters
-        basis[i, :] = cos(i * samples)
+        for j in 1:length(samples)
+            basis[i, j] = cos(i * samples[j])
+        end
     end
 
     basis *= sqrt(2f0/ninput)