See here for an excellent solution to generating your noise from one of your previous questions:
You can use the code from the previous answer I gave you to add a rise-fall time for 10 ms and the other stimulus.
the 10 dB SNR should also be the same. Example below.
%set-up parameters
fs=44100; %CD quality - also conveniently divisible by 30 and 25
stim_dur=.025; %duration of puretone in seconds
noise_dur=.200; %duration of noise in seconds
ISI_dur=.020; %ISI duration in seconds
ramp_dur=.010; %ramp duration in seconds
t=0:1/fs:stim_dur-1/fs;
f=1000;
%create noise
nsamples = floor(noise_dur*fs);
noise_all_Hz = randn(nsamples,1);
noise = bandpass(noise_all_Hz,[950 1050],fs);
noise=noise';
%create 1000 Hz tone
xt=sin(2*pi*f*t);
%setup ramp
rampSamps = floor(fs*ramp_dur);
window=hanning(2*rampSamps)'; %hanning window is cosine^2 this will change depending on the kind of ramp you want
w1=window(1:ceil((length(window))/2)); %use the first half of hanning function for onramp
w2=window(ceil((length(window))/2)+1:end); %use second half of hanning function of off ramp
w_on_xt = [w1 ones(1,length(xt)-length(w1))];
w_off_xt = [ones(1,length(xt)-length(w2)) w2];
w_on_noise = [w1 ones(1,length(noise)-length(w1))];
w_off_noise = [ones(1,length(noise)-length(w2)) w2];
%ramp stimuli
noise_ramped = noise.*w_on_noise.*w_off_noise;
xt_ramped = xt.*w_on_xt.*w_off_xt;
% scale
rms_xt_ramped=rms(xt_ramped); %check the average intensity of the ramped 500 Hz signal
amp_10dB=10^(-10/20)*rms_xt_ramped; %find the new amplitude that is 10 dB lower
%normalize the xt2_ramped stimulus and then scale to -10 dB
noise_ramped_norm=noise_ramped./rms(noise_ramped);
noise_ramped_10dB=noise_ramped_norm.*amp_10dB;
%check
rms_noise_ramped=rms(noise_ramped_10dB);
20*log10(rms_xt_ramped/rms_noise_ramped)
%generate ISI
ISI=zeros(ISI_dur*fs,1);
%final stimulus
out=[noise_ramped_10dB';ISI;xt_ramped'];
plot(out)
sound(out,fs)
