I have not received the product yet.

The performance here is a fine one. It's good to hear Vickers in a Verdi role other than Otello. His Riccardo is noble, passionate, and well-sung. He doesn't sing the top C with Shuard at the end of their duet, but he is one of the few tenors who sings the optional lower line in his Act 1, scene 2 canzone. Shuard is an excellent Amelia who sings the oft-omitted cadenza at the end of "Morro". Glossop sings a truly distinguished Renato and Verrett is a major figure as Ulrica (I think this was the only time she did the role on stage). Popp is an adorable Oscar, rather unappreciated by the audience (she gets no applause at the end of "Saper vorreste"). Kertesz leads a lively performance with the occasional odd texual choice (Vickers doesn't sing several lines after he is shot - did he forget them?) The voices are recessed though still audible. The tape source is uneven, the tapist having to contend with a sometimes unruly audience (a woman can be heard briefly sobbing during "Eri Tu" - I kid you not!). But Ballo lovers should hear this. Overall it's not quite as good as an earlier Ballo from Covent Garden (Vickers, Shuard, Bastianini, Resnik) that was released officially by the Royal Opera, but if you can't find that one this one has some special moments too.

There was obviously a good performance going on here but it is difficult to stay with it because of the distant and muffled sound.

an excellent all-star performance with moderate sound

Despite the poor sound this is a very fine performance. Shuard and Vickers had been singing these roles together since 1957 (originally in English) but these were to be the last. As fine a supporting cast as can be imagined and a rare souvenir of Kertesz in the opera house.