Καλησπέρα,
Issue no.1 : Your queries are very interesting. I see that maria_gr has suggested amongst others "The Olympians", "Pasxalis", Kazantzidis etc...Sure, they are oldies and very popular oldies. However, your friend's father is likely to go further back in time. I have four names of artists for you. The reason I chose them is that you mention something about him playing the guitar and being conservative. In my perception, a 70 year old person that plays the guitar and is quite conservative
MUST HAVE BEEN LISTENING to folks like Toni Maroudas (Tόνυ Μαρούδας), Nick Gounaris (Νίκος Γούναρης) and Fotis Polymeris (Φώτης Πολυμέρης). They fit the profile of conservative, retro artists that liked the guitar and used to gather around the "Plaka" area in Athens, a quite famous place for artists gatherings and still nice-ish today. Fish also for the "Katsamba brothers" (αδερφοί Κατσάμπα), very skilled singers and guitar players of the time, with Cinematographic participation (as Azimut suggested) that are actually from my home city!!!
You know, I could be wayyyyy off in my suggestion, but I bet that at least one of these names is going to make him very excited and must be in his original collection. I would be willing to bet money on that.
Issue no.2: Talking about old discs here are some answers:
1)OCDR stands for Over-sampling and Comparison Digital Restoration. It is an entire range of procedures where sound is recorded from special turntables or tape players, gets digitized and all the "scratch and rumble" phenomena are extracted by means of special computer software to make crystal clear sound that closely matches the original to the greatest possible extent.
2)An OCDR certified studio is one that contains equipment to perform not only the recording and processing, but also the treatment of the original analog media in order to maximize the effectiveness of an OCDR recording. So, a media specialist will examine the condition of a disk or tape, will judge if surface work is needed prior to the recording and will quarantee the optimal removal of dust and other substances that might interfer with the quality of sound. This is actually the most expensive step.
3)Your friend's father was right when he does not trust third party solutions. DO NOT apply anything on the media surface. There are some anti-static solutions that could prevent the depositing of dust particles, but any other chemical (aceton, chlorine, benzin) could damage them. If you decide to restore them, leave the process to a specialist and I assure you the chemicals used are not widely available in the market.
4)I have sent you details of an OCDR enabled studio in Athens in a private message. I used to work there, and they do a good job as they have been a subcontractor of the Greek Broadcasting Corporation (ΕΡΤ) archive, the largest archive of Greek music. You can safely trust them. Prices vary. As a sample, they might ask anything from 25 - 30 pounds for LPs (33 1/2, 45ers) up to 150 pounds for older 78 rpm "Shellac" gramophone records that are broken in pieces . You can ask them for a better price if you have many disks and they are usually reasonable to respond. Use my name to them as a reference
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