options available for visualizing a matrix type data frame in R
I'm expecting your data in this form (use melt to transform the data):

   type product value
1   A1      p1   158
2   A2      p1   343
3   A3      p1   247
4   B1      p1   400
5   B2      p1   398
6   B3      p1   408


You may easily (using lattice package) draw a barchart diagram.

Personally, I'd switch to heatmap only after this diagram is no more feasible due to large number of levels in the product or channel factors.

library(lattice)
barchart(product~ value | type,
data =  dfp,
scales=list(x=list(rot=90, cex= 1 ),y=list(cex=1)),par.strip.text=list(cex=1), origin = 0,  
ylab="Product", xlab="Volume", 
main= "Matrix Visualization")




Of course you may also swap the dimensions by changing the formula. Use the parameter layout to align the barchart based on the number of levels.

barchart(type~ value | product,
data =  dfp,
scales=list(x=list(rot=90, cex= 1 ),y=list(cex=1)),par.strip.text=list(cex=1), origin = 0,  layout= c(5,1),
ylab="Channel", xlab="Volume", 
main= "Matrix Visualization")