Given the interest in replacement speakers I have a friend over now who is a sound engineer of 30 years. He has worked in uk recording studios, theatre, musical shows round the world. Of my 4 games my 1981 Vector is his favourite, but that is another story.
Note - this is aimed at WPC games and early 1980s solid state Bally games only
I have shown him around my 1981 vector (1 amp channel, 1 x 6.5" cabinet floor speaker), wpc shadow (2 separate amp channels for cabinet floor and backbox speakers, 1 x 6.5" speaker in the cabinet, inbuilt crossover) and wpc tz (single channel amp for cabinet floor and backbox speakers, 1 x 6.5" speaker in cabinet, no crossover)
We tested the sound in all three games with his ears. The simplicity and cost effectiveness of his advice might surprise you, but I am following it
1. The Sony backbox speakers I recommended last week are a no brainier at £10 a pair for dual driver xs-gt1328f. But you should enlarge the right hole to get the best out if them. Remove the filter capacitor on your stock right speaker as this is acting as a crossover and it is not needed with the Sony ones
2. Do not mess about enlarging the cabinet floor speaker hole (5.5") on any of these games. Not worth the effort, mess.
3. Use a direct replacement 6.5" speaker in the cabinet floor, firing through the original 5.5" hole. He thought using an 8" speaker through the 5.5" hole was pointless due to restrictions in the flow of air and may be worse than using a 6.5" right size one down there
4. Do not bother with a crossover on Twilight Zone. Remember that Vector only has one speaker so does not need one. Shadow has a crossover built into the amplifier board. He saw no issue with the cabinet floor speaker paying some treble as well as bass on Twilight Zone
5. Buy the Sony XS-GT1728F. These are also a screaming bargain on eBay at £18 a pair including postage. Argos has incorrectly described the size again! And offers the cheapest price. These are described by Sony as 17cm which is near as dammit 6.5". I do not know whether they are a direct drop in, or whether use of a file may be required to make them fit. But these speakers do offer a lot of mounting holes so I am hopeful it will be very easy to install them. I will let you know as I have just ordered mine. Thesè are from the same range as the 5.25" speakers above. They are dual driver speakers but he saw this as a non issue given the poor speaker location and that it is firing sound into the floor. "So what if some treble is fired at the floor? "As a two way speaker this should have a significant benefit on Vector as the current rubbish speaker is one way
6. Buy a cheap 100 k ohm mono potentiometer (about £1) to balance the backbox and cabinet speakers IF necessary. He just says try without to start with as these speakers are all from the same current Sony range. But, the backbox speakers are less sensitive at 88 db, the cabinet is 91 db. But as the cabinet speaker is pointed at the floor he thinks this may quieter them down that little bit. Obviously no need for the potentiometer in the single speaker vector game
7. Don't bother replacing the skinny original speaker wiring "just use the sh1t that is there" as the amp is old and is running 4 ohm speakers. So a change in speaker wire resistance might have an adverse effect
so an upgraded speaker set for less than £30
Will revert when my cabinet floor speakers arrive and are installed in the three games.
Note - this is aimed at WPC games and early 1980s solid state Bally games only
I have shown him around my 1981 vector (1 amp channel, 1 x 6.5" cabinet floor speaker), wpc shadow (2 separate amp channels for cabinet floor and backbox speakers, 1 x 6.5" speaker in the cabinet, inbuilt crossover) and wpc tz (single channel amp for cabinet floor and backbox speakers, 1 x 6.5" speaker in cabinet, no crossover)
We tested the sound in all three games with his ears. The simplicity and cost effectiveness of his advice might surprise you, but I am following it
1. The Sony backbox speakers I recommended last week are a no brainier at £10 a pair for dual driver xs-gt1328f. But you should enlarge the right hole to get the best out if them. Remove the filter capacitor on your stock right speaker as this is acting as a crossover and it is not needed with the Sony ones
2. Do not mess about enlarging the cabinet floor speaker hole (5.5") on any of these games. Not worth the effort, mess.
3. Use a direct replacement 6.5" speaker in the cabinet floor, firing through the original 5.5" hole. He thought using an 8" speaker through the 5.5" hole was pointless due to restrictions in the flow of air and may be worse than using a 6.5" right size one down there
4. Do not bother with a crossover on Twilight Zone. Remember that Vector only has one speaker so does not need one. Shadow has a crossover built into the amplifier board. He saw no issue with the cabinet floor speaker paying some treble as well as bass on Twilight Zone
5. Buy the Sony XS-GT1728F. These are also a screaming bargain on eBay at £18 a pair including postage. Argos has incorrectly described the size again! And offers the cheapest price. These are described by Sony as 17cm which is near as dammit 6.5". I do not know whether they are a direct drop in, or whether use of a file may be required to make them fit. But these speakers do offer a lot of mounting holes so I am hopeful it will be very easy to install them. I will let you know as I have just ordered mine. Thesè are from the same range as the 5.25" speakers above. They are dual driver speakers but he saw this as a non issue given the poor speaker location and that it is firing sound into the floor. "So what if some treble is fired at the floor? "As a two way speaker this should have a significant benefit on Vector as the current rubbish speaker is one way
6. Buy a cheap 100 k ohm mono potentiometer (about £1) to balance the backbox and cabinet speakers IF necessary. He just says try without to start with as these speakers are all from the same current Sony range. But, the backbox speakers are less sensitive at 88 db, the cabinet is 91 db. But as the cabinet speaker is pointed at the floor he thinks this may quieter them down that little bit. Obviously no need for the potentiometer in the single speaker vector game
7. Don't bother replacing the skinny original speaker wiring "just use the sh1t that is there" as the amp is old and is running 4 ohm speakers. So a change in speaker wire resistance might have an adverse effect
so an upgraded speaker set for less than £30
Will revert when my cabinet floor speakers arrive and are installed in the three games.
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