I will probably be sent to hell for this, but here goes anyhow.
Are the any plans by the record company/ Queen Productions Ltd to do some future releases of the earlier albums as some of the production recording techniques sounds very dated, whereas mixing songs with current technology might give some of the songs a new life, listening to the later albums you get this huge expansive sonic experience whereas some of the older stuff sounds quiet like intro to Fat Bottom Girls.
By the way production of Live Killers was awful sorry!! by the way a Fan not a Critic.
This topic is in the wrong place. But to answer your qustion read this link: link
try the 2001 Japanese remasters for some of the records. They´re excellent!
Take care