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Are there any Sega pinballsound improvement kits made ?

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bpositive

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Dec 25, 2009, 4:11:14 PM12/25/09
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Greetings and happy holidays. I am getting some service time in with
the big snow we have had in Va. Was going thru some of my Sega games.
Star wars trilogy used as this example. By design the game has only
one backbox speaker. RGB post by Orin Day states they removed some of
the components from the sound board and went to one speaker to cut
costs. My machine has bad cabinet speaker. I was wondering if anyone
has come out with a kit to improve overall sound package for these
games. Pinball pro speakers avaible , would someone have comment on
weather they are worth the money? Is there a sound card redesigned
with the circuit avaible to run a second backbox speaker ? If not
could a earlier or later board be retrofitted for this application ?
TIA for the input. Shane

Captain Neo

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Dec 25, 2009, 8:39:07 PM12/25/09
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My SST has the same sound system your SW has. I replaced all the
speakers from parts-express.com. Put 2 4" mini woofers in teh backbox
with an L pad, and standard 8" in the cabinet. cost me about $40
total and sounds awesome now. Actually has bass and doesn't sound
tinny.

bpositive

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Dec 25, 2009, 10:26:07 PM12/25/09
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Did you have to modify the sound card for the added speaker? Would you
have the item numbers you bought from parts express? Thanks Shane

Brad

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Dec 25, 2009, 11:01:02 PM12/25/09
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Neo, you are too advanced for some of us.

A. What is an L pad
B. Did you do any other changes or are both speakers just playing the
same channel and sounds?
C. Any part numbers would be great.

bpositive

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Dec 26, 2009, 10:14:03 AM12/26/09
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Definitely lots of speakers on that sight to choose from. Would
someone know the wattage output from the sound circuit boards (star
war trilogy,SST,Viper ) ? Is the output the same for all of these
games ? Thanks again for the follow up information. Shane

paragon66x

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Dec 26, 2009, 8:48:44 PM12/26/09
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Neo - please post a parts list if you would. Many of us out here that
would like to follow suit. John

kreed

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Dec 26, 2009, 9:27:13 PM12/26/09
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an L pad is basically a high wattage potentiometer (like a rotary
volume control, but high power) that you insert in speaker lines to
reduce volume.

It is a variable resistor, designed in such a way as to maintain the
load across the amplifier regardless of the position of the level it
is adjusted to.

Another similar unit is the T pad, but not used much these days.
Here is an article on the various "pads" used in audio.

http://www.uneeda-audio.com/pads/


In this case it would have been done as one speaker was probably more
efficient than the other (IE: louder), and its volume has to be
reduced so that its the same from both.

AS for your original question, you could try adding the components to
the board for the extra channel, but there is NO guarantee that there
would be any audio output available from the microprocessor system to
drive it.

Even if the software had been designed to produce stereo sound, and
then the bean counters decided to cut one channel and make it mono -
they could either have changed the software to output the audio in
mono to the exisiting channel, or could have put a jumper on the board
to divert both channels to the one amplifier.

If they did the jumper, then you could install the extra components
and remove the jumper, you might then get the stereo sound.

If it was made mono in software, short of building some sort of
"stereo simulator" (used to pop up in electronics hobby magazines
years back but haven't seen one of these in many years) or you are
stuffed.


bpositive

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Dec 26, 2009, 10:58:34 PM12/26/09
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Good info on the pads themselves . I would like to see a circuit
diagram . Where the L pad is used is unclear. Would it be in series on
the cabinet or the new set of two backbox speakers. Always something
to learn. Thanks again Shane

Brad

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Dec 26, 2009, 11:06:20 PM12/26/09
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Great post here. I'm hoping we can have all of the details on here
since this is probably a pretty common thought to those who own these
games. And exactly how everything is all hooked up would be
beneficial. BRad

kreed

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Dec 26, 2009, 11:25:06 PM12/26/09
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you would use it on whatever speaker was too loud in comparison to the
other.

In this case it would likely be the backbox speaker. The under
cabinet speaker (lower frequency) would lose much of its sound energy
in relation to anyone standing in the normal playing position - as its
pointing to the floor which is probably carpeted and absorbs sound, as
well as away from the listener, and the mid/high (if in the headbox
facing forward) are in an optimum listening position, pointing
straight at the player. These will sound a lot "louder" and will need
their volume to be reduced.

The manufacturer probably specified speakers that were well matched to
avoid these problems.

If you are putting in aftermarket speakers, especially if adding a
second speaker in the headbox for "stereo" - these probably would not
be matched, and could be unequal volume. The L pad is used to reduce
the volume of the most efficient speaker(s) in order that it matches
the other. Failure to do this would result in too much treble, or too
much bass depending on which speaker is more efficient than the other.

You put the L pad in the line to the speaker (s) in question, and
adjust it for a good sound balance that you find the most pleasant.


When buying an L pad, there should be instructions enclosed on how to
wire it into the speaker in question.

If you have wire wound resistors (say 5W or more) lying around in your
junk box, you could "roll your own" fixed attenuator (instead of the L
pad) with a bit of mucking around.

If you have an assortment of 5w resistors, you could experiment with
them to get the required sound level.

Captain Neo

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Dec 27, 2009, 2:07:30 PM12/27/09
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The Lpad is used for the top back box speakers. You have to put both
speakers in series as the components on your board for the 3rd speaker
have been eliminated from the board due to cost cuts.

The Lpad reduces the volume for the top backbox speakers. Hence, you
can turn up the volume a lot more without making the whole game loud
and increasing the cabinet bass volume. Giving that ummph, you want in
the cabinet.

Also, the 4" woofers in the backbox help eliminate a lot of that tinny
sound that SST has. my SST sounds awesome now and 1000x's better.

bpositive

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Dec 28, 2009, 6:34:24 AM12/28/09
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Neo Thanks for the update. If you can visit the speaker site can you
tell us which of the many speaker choices worked for you. Did you
purchase the L pad there as well? Thanks again! Shane

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