There are hints of foul play in the taglines on the cover: a rare treasure ... 15 unreleased songs revived and digitally mastered in 2009. The word revived when Sanjeev Kohli is nearby can mean only one thing. More evidence comes from two places.
The first is this bit of text below the track list:
all songs composed and recorded by madan mohan during his lifetime
these songs were from shelved films between 1964 and 1972
instruments added in 2009 to enhance the quality of old recordings
The second is the credit for additional musicians in the inlay sheets (Incidentally, technical supervisor Victor Dantes was a comrade-in-arms in a similar successful experiment called the "Legends" series).
This is what happens when you have people with insufficient technical chops to pull off a remastering job. One must also credit the purchasing majority that doesn't really care.
I have one serious complaint against the ‘Legends’ series of music compilations. I feel that by adding reverb, the digitized songs on these CDs lost their rich depth of original vocals and acoustic orchestration. They sound hollow!
You are right in your observation. But the reverb effect was added to nullify the hiss and scratchy sounds of old records. That does muffle the sound a bit but the general public seemed to have liked the sound! Perhaps the connoisseurs might feel differently about it.
Earlier in the interview, Kohli talks about Tere Bagair (I have taken the liberty of emphasising the portions of interest for you, O patient reader)
Now the new album- 'Tere Bagair' (released by Yashraj Music) will present all the ten songs from 'Treasure Unrevealed' in full, extended versions and it will also have five more tracks originally recorded by Madan Mohan. This album will be a treat not only for the fans of Madan Mohan but also for the fans of singers like Lata, Asha, Rafi and Kishore because they will get an opportunity to experience many original Madan Mohan recordings in their favourite singer's voice. Moreover these songs were previously either unreleased or inaccessible. Even those listeners who had already heard 'Treasure revealed' would find many new things in 'Tere Bagair'. The recording quality of the album is excellent since the master tapes have been used to reproduce the songs. In some songs, I have re-recorded the tabla tracks and added some harp sounds but even that is done in such a way that it would perfectly fit in the sound of the 60s, when those songs were originally recorded.
You can't compare 'Tere Bagair' to 'Veer Zaara' because ' Tere Bagair' is an album of out and out Madan Mohan originals whereas in 'Veer Zaara', his tunes were modified to suit the times and also the film's requirements.
This, ladies and gentlemen, is a man of commerce talking.