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Apple IIGS Stereo Sound Card - Interest?

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Drew

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Oct 30, 2009, 7:16:57 PM10/30/09
to
Hi,

I have been working on reproducing the TDX Stereo Sound card using the
FAQ information as well as the slight modification using a quad amp as
already outlined by Polymorph.

My next stage is to get from breadboard and on to PCB in some form via
copper board etc. I am contemplating taking this further and actually
to get this fabricated and offer them back to the community at cost
for component and manufacture etc (i am not doing this to make money
lol). I still have things to sort out in terms of cable placements
etc, but i want to gauge interest if anyone would actually be after
one. I kinda reckon it will come to something like £30 - £40 for a
card....not really sure tbh.

If anyone is interested drop me a reply so i can see if its really
worth me getting them made etc.

If anyone has any other improvements to the TDX/Polymorph version then
drop me a note and I will try and encompass it into the card.

You can follow my progress at http://drewbiegs.blogspot.com

Cheers
Drew

Toinet

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Oct 31, 2009, 4:43:47 AM10/31/09
to
On 31 oct, 00:16, Drew <goggled...@gmail.com> wrote:
> If anyone is interested drop me a reply so i can see if its really
> worth me getting them made etc.
>

Count me in, Drew.

antoine

Drew

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Oct 31, 2009, 5:47:30 AM10/31/09
to

Kool, That is one :).

One thing i am having trouble deciding how much effort to put into is
getting the audio cable to the back of the computer. In fact the cable
bit and the audio connector is easy. I am struggling to find a plate
to mount on to the rear of the case. Anyone have any ideas of where i
can get a plate from? I haven't spent that much time looking as
currently i am going to just mount the 3.5mm jack to the card to get
the initial card done, but thought i would ask to see if anyone knows
an off the shelf part :).

Cheers
Drew

Mike

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Oct 31, 2009, 9:52:07 AM10/31/09
to
On Sat, 31 Oct 2009 02:47:30 -0700 (PDT), Drew <goggl...@gmail.com>
wrote:

Count me in, too!

- Mike

sicklittlemonkey

unread,
Oct 31, 2009, 11:49:18 AM10/31/09
to
On Oct 31, 8:16 am, Drew <goggled...@gmail.com> wrote:
> If anyone has any other improvements to the TDX/Polymorph version then
> drop me a note and I will try and encompass it into the card.
>
> You can follow my progress athttp://drewbiegs.blogspot.com

Drew, I had a quick look but couldn't tell:
Are you planning for this to occupy a slot?

Interested, but would prefer that it didn't occupy a slot.

Cheers,
Nick.

Drew

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Oct 31, 2009, 12:41:17 PM10/31/09
to

Hi,

I haven't quite decided yet what to do. My initial idea was a slot
based card, but the more i think of this i might offer the card in two
variations with modular audio outputs as well. I.e a slot based card
and a no slot based card (In the testing of the breadboard all i did
was to wire directly in to the -5 and +5 of the power connector so in
theory i could use a piggyback connecter) all using the same
fundamental circuit. I will have a better idea of what is realistic
once i have a prototyope completed and tested in the next 2 weeks or
so to make sure all sounds clear and no issues come out in the chip
placement.

Once i get idea of cost to actually make the boards, I will post back
estimated costs. At the moment the component cost is only ~£9

Drew

td...@apple2.info

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Oct 31, 2009, 12:44:15 PM10/31/09
to
Perhaps .. there's some interest in these things, too ..

http://17500mph.com/photos?g2_itemId=193

Garberstreet Electronics

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Oct 31, 2009, 2:43:23 PM10/31/09
to

<td...@apple2.info> wrote in message news:9ee7e7ad-3d6a-
4772-b4e6-a...@b2g2000yqi.googlegroups.com...
> Perhaps .. there's some interest in these things, too ..
>
> http://17500mph.com/photos?g2_itemId=193

Well, that would depend on what they are, wouldn't it? ;-)

Bill Garber of Garberstreet Electronics
http://www.garberstreet.com


atfphot...@gmail.com

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Oct 31, 2009, 4:00:54 PM10/31/09
to

Cool blog, Drew!

ATF

atfphot...@gmail.com

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Oct 31, 2009, 4:01:53 PM10/31/09
to
On Oct 31, 12:44 pm, td...@apple2.info wrote:
> Perhaps .. there's some interest in these things, too ..
>
> http://17500mph.com/photos?g2_itemId=193

A daft question?

What are they?

Haha..

ATF

Polymorph

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Oct 31, 2009, 5:52:36 PM10/31/09
to

I always planned to make a run of these things too, except I never
managed to find the time. I am considering making another one for the
kids IIgs though, but if your price is right (and if I'm feeling
particularly lazy), I might even buy one of yours. Alternatively, I
might go into competition with you... lol :-)

Maybe you could record something from the IIgs using the TDX and
compare the output to mine. The easiest way to do this is to blug the
output of the TDX into the line-in of a PC (or Mac) and record it
using whatever software you use to record sounds. I have mine
installed in a ROM3 IIgs, so I may get cleaner audio if yours in a
ROM01. But I have a ROM01 here I could hook up too, if required. I
actually have my IIgs permanently hooked up to the line-in of my
desktop so that it pipes through my Logitech 5.1 speakers (albeit only
in stereo). It sounds awesome!

I changed my board (ages ago now) to have the 3.5mm jack mounted to
the back of the case as opposed to directly on the card like it is in
the pics on my site. I hacked an old PC slot cover (the metal thingy
you use to cover unused slots) and screwed it into an unused slot
opening on the IIgs. But this just rounds out the real "hacker" look
to mine. I'm guessing you will want something with a tad more
polish. ;-)

BTW, as a comparison, I remember mine costing around AUS$20 for the
components, when assembled on a prototype board. So I expect a
professionally done PCB would cost quite a bit more.

Anyway, good luck! I look forward to seeing the end result.

Cheers,
Mike

http://apple2.sytes.net/

Poster

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Oct 31, 2009, 6:43:59 PM10/31/09
to
In article
<937897db-561e-4a38...@w19g2000yqk.googlegroups.com>,
Drew <goggl...@gmail.com> wrote:

I'm interested also.

--
Poster

www.intaligo.com I6 libraries, doom metal, Building
sturmdrangif.wordpress.com Game development blog / IF commentary
Seasons: fall '09 -- One-man projects are prone to delays.

Mike Spurgeon

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Oct 31, 2009, 8:35:43 PM10/31/09
to
Garberstreet Electronics wrote:
>
> <td...@apple2.info> wrote in message news:9ee7e7ad-3d6a-
> 4772-b4e6-a...@b2g2000yqi.googlegroups.com...
>> Perhaps .. there's some interest in these things, too ..
>>
>> http://17500mph.com/photos?g2_itemId=193
>
> Well, that would depend on what they are, wouldn't it?

Quite a few were explained in the headers...

Michael J. Mahon

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Oct 31, 2009, 10:33:32 PM10/31/09
to
Polymorph wrote:

> I changed my board (ages ago now) to have the 3.5mm jack mounted to
> the back of the case as opposed to directly on the card like it is in
> the pics on my site. I hacked an old PC slot cover (the metal thingy
> you use to cover unused slots) and screwed it into an unused slot
> opening on the IIgs. But this just rounds out the real "hacker" look
> to mine. I'm guessing you will want something with a tad more
> polish. ;-)

I usually drill/cut a hole in a plastic slot cover for the NadaNet
adapter's RCA socket. It has some "flex", but if you're careful
and don't plug and unplug a lot, it works just fine and looks good.

-michael

NadaNet 3.0 for Apple II parallel computing!
Home page: http://home.comcast.net/~mjmahon/

"The wastebasket is our most important design
tool--and it's seriously underused."

magnusfalkirk

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Oct 31, 2009, 10:55:23 PM10/31/09
to

Drew,

depending on the cost I'd be interested in one.

Dean

sfahey

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Oct 31, 2009, 11:42:28 PM10/31/09
to Toinet
To: Toinet
Re: Re: Apple IIGS Stereo Sound Card - Interest?
By: Toinet to comp.sys.apple2 on Sat Oct 31 2009 01:43 am

I'd like to know more.

Sean Fahey
www.a2central.com
bbs.a2central.com

Drew

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Nov 1, 2009, 3:47:50 AM11/1/09
to

> I'd like to know more.
>
> Sean Faheywww.a2central.com

Hi,

Well i am in really early stages and will have more of an idea of what
i can achieve once i move on to a copper board. I have lots of ideas
on how to do things, but my end goal will be to try get the end
product looking professional. Though i will have to put the components
on myself i hope for the board, cables and connectors to all look as
if it was a real off the shelf product :) .

I will updating my blog as i go along, so check it to see where i am.
I don't have a completion date yet though.

Drew

nyder

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Nov 1, 2009, 5:04:37 AM11/1/09
to
Sorry if this is easy found info, but can somone explain to us newbs
what the benefits of this is?

I know the GS can produce stereo sound, and I know it only has a mono
output.

Does alot of programs support stereo sound?

And what exactly are you doing? It's obvious it's more then making a
secondary jack for stereo, and I'd like to know what exactly your
doing, just for the learning factor.

thanks

Drew

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Nov 1, 2009, 5:33:50 AM11/1/09
to

Hi,

Well what i am doing is nothing new and I am only putting something
together that other people have already worked on. The Apple IIGS
Hardware Reference book has a rough outline on what is required to
allow the IIGS to output Stereo sound and in 1992 Jeff Hurlburt
produced a circuit diagram of what would be required which you can see
in the A2 FAQ (http://home.swbell.net/rubywand/Csa2SOUND.html).

Polymorph used a quad amp rather than the two TL082 as you can see
from his website http://www.cirruscomms.com.au/~mike_stephens/apple2/TDX_Stereo_Card/index.html
and i am using the TL084NI in the card i am producing. This means the
board only requires two ICs the demultiplexer and the amps (within one
package).

If you read the FAQ that should outline what is actually going on.

Hope that makes it clearer :-) and there are plenty of games that
support stereo sound.

Drew

Polymorph

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Nov 1, 2009, 5:50:52 AM11/1/09
to

The IIgs has a socket on the motherboard that provides access to the
stereo signals (well actually, more than this but I digress). However,
a circuit like the TDX board is required to separate and amplify the
audio signals so that they are ready for listening - this is where
IIgs stereo boards come in. And yes, a lot of IIgs programs *do*
produce stereo sound. I would say many (most?) games do, and most
(all?) of the specific IIgs music creation applications do. Hooking a
IIgs up to decent speakers also helps, but if you use the mono plug
you most likely will only get audio from one speaker.

I would certainly recommend anyone to add a stereo board to their IIgs
if they really want to witness what the 'S' in IIgs really stands
for... :-)

Cheers,
Mike

macdog

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Nov 1, 2009, 7:18:37 AM11/1/09
to

> If anyone is interested drop me a reply so i can see if its really
> worth me getting them made etc.


I'd be interested.

Jamie.

Bill Buckels

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Nov 1, 2009, 9:02:49 AM11/1/09
to

"Drew" <goggl...@gmail.com> wrote:
> I kinda reckon it will come to something like �30 - �40 for a card....

Hi Drew,

Count me in.

Also I wouldn't expect you to be able keep the cost that low although I have
every confidence that you will do your best:)

Regards,

Bill


Michael J. Mahon

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Nov 1, 2009, 3:39:25 PM11/1/09
to

Since a stereo demultiplexer simply puts all the even-numbered
Ensoniq channels on one side and all the odd-numbered channels on
the other side, any program that uses more than one oscillator will
produce stereo sound.

A smaller number of programs will have consciously assigned instruments
to even or odd oscillators to produce _intentional_ stereo sound.

Toinet

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Nov 2, 2009, 2:15:26 AM11/2/09
to
Hi Drew,

Will your board allow sound input as well as sound output? I mean
"numérisation du son" (sound digitization)

antoine

Bill Buckels

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Nov 2, 2009, 4:52:04 AM11/2/09
to

"Toinet" <antoine...@laposte.net> wrote:

>Will your board allow sound input as well as sound output? I mean

>"num�risation du son" (sound digitization)

Hi Tony,

That would be good if Drew's board provided recording as well as playback
functionality. (i.e. ADC input as well as DAC output).

Bill


Drew

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Nov 2, 2009, 5:49:34 AM11/2/09
to
On 2 Nov, 09:52, "Bill Buckels" <bbuck...@mts.net> wrote:

> "Toinet" <antoine.vig...@laposte.net> wrote:
> >Will your board allow sound input as well as sound output? I mean
> >"numérisation du son" (sound digitization)

>
> Hi Tony,
>
> That would be good if Drew's board provided recording as well as playback
> functionality. (i.e. ADC input as well as DAC output).
>
> Bill

Hi,

At the moment it will be output only. I have thought about input, and
i 'might' look at this at a later date. This is all new to me and am
keen to get something produced and then look at how i can improve
things maybe on a version 2.0 board, but to be honest if i was going
to do the input i would need lots of help from the group :).

Drew

sfahey

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Nov 2, 2009, 9:25:40 AM11/2/09
to Drew
To: Drew

Re: Re: Apple IIGS Stereo Sound Card - Interest?
By: Drew to comp.sys.apple2 on Mon Nov 02 2009 02:49 am

> to do the input i would need lots of help from the group :).

Drew, is this project a "more the merrier" or do you want to keep it on CSA2
only for now? If you were considering putting these together, and making a
little $$$ for your trouble, I can put something on A2C but it might mean a lot
more interest than you're ready for. <shrug> You're blog has been in our
recommended blog list for several weeks so maybe it won't matter.

Sean Fahey
www.a2central.com
bbs.a2central.com

Drew

unread,
Nov 2, 2009, 9:56:30 AM11/2/09
to
On 2 Nov, 14:25, "sfahey" <sfa...@a2central.com.remove-4rb-this>
wrote:

Well at the moment, best to keep it just to CSA2 until i have
prototype board done. Once i really know the effort to put these
together happy for the world to know lol. Thanks for putting me on the
recommend blog list :)...btw its Drewbie GS ;)....not the greatest
name i know lol

Drew

sfahey

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Nov 2, 2009, 11:29:44 AM11/2/09
to Drew
To: Drew
Re: Re: Apple IIGS Stereo Sound Card - Interest?
By: Drew to comp.sys.apple2 on Mon Nov 02 2009 06:56 am

> recommend blog list :)...btw its Drewbie GS ;)....not the greatest
> name i know lol

Doh! OK, I've changed it. I usually put people's real names with their blogs
so they are credited. I won't post anything until you're ready and want me to.

Sean Fahey
www.a2central.com
bbs.a2central.com

Michael J. Mahon

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Nov 2, 2009, 12:34:18 PM11/2/09
to
Drew wrote:
> On 2 Nov, 09:52, "Bill Buckels" <bbuck...@mts.net> wrote:
>> "Toinet" <antoine.vig...@laposte.net> wrote:
>>> Will your board allow sound input as well as sound output? I mean
>>> "num�risation du son" (sound digitization)

>> Hi Tony,
>>
>> That would be good if Drew's board provided recording as well as playback
>> functionality. (i.e. ADC input as well as DAC output).
>>
>> Bill
>
> Hi,
>
> At the moment it will be output only. I have thought about input, and
> i 'might' look at this at a later date. This is all new to me and am
> keen to get something produced and then look at how i can improve
> things maybe on a version 2.0 board, but to be honest if i was going
> to do the input i would need lots of help from the group :).

Since the Ensoniq ADC input (mono) is on the same connector as the
multiplexed outputs, you already have access to the input.

All that's needed is suitable amplification for your intended input
(required for a microphone input) plus an anti-aliasing low-pass
filter--probably another two op-amps as active filters.

The net impact to the bill of materials would be another two
or three op-amps (in one chip), about a dozen passives (resistors
and capacitors), and an input jack--plus a gain control if one is
not available off-card.

If a low-level (microphone) input is provided, some care should
be exercised in laying out the card to avoid noise pickup.

Drew

unread,
Nov 23, 2009, 4:20:47 PM11/23/09
to
On 2 Nov, 17:34, "Michael J. Mahon" <mjma...@aol.com> wrote:
> Drew wrote:
> > On 2 Nov, 09:52, "Bill Buckels" <bbuck...@mts.net> wrote:
> >> "Toinet" <antoine.vig...@laposte.net> wrote:
> >>> Will your board allow sound input as well as sound output? I mean
> >>> "numérisation du son" (sound digitization)

Hi,

I have completed the prototype card (http://drewbiegs.blogspot.com),
but seems the hiss that was on the breadboard is on the real card as
well, specifically on the right speaker. I was wondering if anyone had
some suggestions on a good starting point? possibly the layout of the
board, but I am not expert on what can cause issues with audio on
PCB...

Any help would be appreciated :)

Drew

Steve

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Nov 23, 2009, 6:41:56 PM11/23/09
to

Hi Drew,

Nice looking card! The fabricator has done a great job on the matt
green.

As for noise, I usually find power is a key contributor for noise.
Some low noise linear regulators (10uV/RMS) with high PSRR can really
make a difference, especially if you have stage gains around 20db and
above. Its amazing how much supply noise gets amplified up into the
output. Killing it at the source is easier than removing it from the
output.

Do you know for sure its white noise? (hiss) - is there any sign of
digital noise? When the floppy drive operates, do you notice any
change in the noise level for example?

steve

> Drew- Hide quoted text -
>
> - Show quoted text -

Toinet

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Nov 23, 2009, 7:35:47 PM11/23/09
to

Good job Drew,
Keep up the good work.
I have no HW skills, I let others help you.
antoine

Drew

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Nov 24, 2009, 2:54:19 AM11/24/09
to
> Hi Drew,
>
> Nice looking card! The fabricator has done a great job on the matt
> green.

Thanks :-), shame it didn't work properly first go :(, but all part of
the fun :-)

> As for noise, I usually find power is a key contributor for noise.
> Some low noise linear regulators (10uV/RMS) with high PSRR can really
> make a difference, especially if you have stage gains around 20db and
> above. Its amazing how much supply noise gets amplified up into the
> output. Killing it at the source is easier than removing it from the
> output

Do you add the linear regs to the board itself ?

> Do you know for sure its white noise? (hiss) - is there any sign of
> digital noise? When the floppy drive operates, do you notice any
> change in the noise level for example?

Tonight I am going to connect a floppy drive and see if that adds
noise, and also switch the outputs of left and right from the MC1402B
chip to see if the white noise follows. If it does then at least i can
eliminate half the circuit i.e the TL084 Amp part. I still have the
bread board made up, so at least i have something to play with still.

Also going to run through the circuit to see if i can see any obvious
issues.

Thanks
Drew

Michael J. Mahon

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Nov 24, 2009, 3:48:31 AM11/24/09
to
Drew wrote:
>>Hi Drew,
>>
>>Nice looking card! The fabricator has done a great job on the matt
>>green.
>
>
> Thanks :-), shame it didn't work properly first go :(, but all part of
> the fun :-)
>
>
>>As for noise, I usually find power is a key contributor for noise.
>>Some low noise linear regulators (10uV/RMS) with high PSRR can really
>>make a difference, especially if you have stage gains around 20db and
>>above. Its amazing how much supply noise gets amplified up into the
>>output. Killing it at the source is easier than removing it from the
>>output

Amen.

> Do you add the linear regs to the board itself ?

Right. You can regulate +12 down to, say, +9 (and -12 down to -9
if you need a negative supply, too).

I fully agree with Steve. For the AppleCrate II audio mixer, I
actually double-regulated +12 down to +5 for the audio stages,
and it eliminated the rampant digital "hash" on the Apple power.

>>Do you know for sure its white noise? (hiss) - is there any sign of
>>digital noise? When the floppy drive operates, do you notice any
>>change in the noise level for example?
>
>
> Tonight I am going to connect a floppy drive and see if that adds
> noise, and also switch the outputs of left and right from the MC1402B
> chip to see if the white noise follows. If it does then at least i can
> eliminate half the circuit i.e the TL084 Amp part. I still have the
> bread board made up, so at least i have something to play with still.

Good plan! Stereo circuits really help with substitution. ;-)

> Also going to run through the circuit to see if i can see any obvious
> issues.

A good indicator that the noise is coming in on the power rails
is to bridge a large electrolytic from the supply rail to ground
(or both if bipolar) very near the audio stages. If you hear a
significant reduction in noise, the power is likely the problem
and regulating down is a good fix.

Another possibility is high frequency oscillation. High-speed
opamps can be unstable if they are not properly bypassed and
compensated. This can be a little trickier to find without an
oscilloscope. A low-pass filter will help here (as would slower
opamps ;-). Also note that an electrolytic bypass does not replace
a ceramic 0.1uF bypass at high frequencies--use both.

BTW, you need a low-pass to eliminate any frequencies above
half the sampling frequency, since they are noise. (My ears
have enough mileage on them that they low-pass everything, but
your's are probably in better shape. ;-)

In addition to an opamp buffer stage, a two-pole active low-pass
filter (plus a single RC pole) will help clean things up.

-michael

NadaNet and AppleCrate II: parallel computing for Apple II computers!
Home page: http://home.comcast.net/~mjmahon

Drew

unread,
Nov 24, 2009, 4:15:43 AM11/24/09
to

Wow...think most of that went way over my head lol. Thanks Michael
will digest all that tonight :).

I do really appreicate everyone's help on this and hopefully this is
just small stumbling block.

Cheers
Drew

Drew

unread,
Nov 24, 2009, 9:22:47 AM11/24/09
to
I was looking at another example Stereo card that was published in a
french magasine, and interestingly their design places an OP-Amp
(LM318) between J25-3 (waveOut) and the MC1402B and a SN7407 hex
buffer between J25-4/6 and the MC1402B IC...sounds like they did this
to clean up the signle before being split out.

Drew


Drew

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Nov 24, 2009, 12:55:48 PM11/24/09
to

Hi, me again :)

Right i attached a floppy drive and using the drive whilst listening
to sound didn't make any difference to the white noise. I switched
round the output from the MC1402B (demux) and the white noise shifted
from right to left. This i would say eliminates the OpAmp TL084 imo.

I am at the moment just attaching a standard pair of headphones to
test with as don't actually have any powered speakers and the line in
to my pc doesnt seem to want to work lol (headphones work fine on
iphone...so don't suspect the headphones). I do have another pair of
better headphones that have a volume control and it would seem that
they don't have the white noise, well it doesn't seem so obvious.

Is it possible that though the card is outputting whitenoise that
certain speakers/headphones will take out the white noise?

Cheers
Drew

Michael J. Mahon

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Nov 24, 2009, 2:01:06 PM11/24/09
to
Drew wrote:
> On 24 Nov, 14:22, Drew <goggled...@gmail.com> wrote:
>
>>I was looking at another example Stereo card that was published in a
>>french magasine, and interestingly their design places an OP-Amp
>>(LM318) between J25-3 (waveOut) and the MC1402B and a SN7407 hex
>>buffer between J25-4/6 and the MC1402B IC...sounds like they did this
>>to clean up the signle before being split out.

Any noise on the +5 supplying the Ensoniq DOC chip will show up in
the analog output. Presumeably, the ROM 3 audio cleanup addressed
this issue. After the noise is injected, you won't be able to clean
up the part that falls within the audio band, so you can't do better
than the DOC output.

Using an opamp to buffer the DOC analog output prior to demuxing
in the 14052 shouldn't be necessary, and may introduce crosstalk
if the opamp bandwidth is limited.

Similarly, the TTL control signal does not need buffering. Seems
like the French design is a bit over-engineered. ;-)

The 14052 analog switch should not couple power supply noise into
its outputs, so you're good there.

The opamp circuits are also quite good at rejecting power supply
noise (though bypassing is always good), so I don't expect that
to be a problem.

If you were generating the analog inputs on the board, then power
supply noise would be a major factor, but the analog signals are
generated by the DOC, over which you have no control.

> Hi, me again :)
>
> Right i attached a floppy drive and using the drive whilst listening
> to sound didn't make any difference to the white noise. I switched
> round the output from the MC1402B (demux) and the white noise shifted
> from right to left. This i would say eliminates the OpAmp TL084 imo.
>
> I am at the moment just attaching a standard pair of headphones to
> test with as don't actually have any powered speakers and the line in
> to my pc doesnt seem to want to work lol (headphones work fine on
> iphone...so don't suspect the headphones). I do have another pair of
> better headphones that have a volume control and it would seem that
> they don't have the white noise, well it doesn't seem so obvious.

Is it just because they are lower volume. or is there a real
difference in just the noise level.

This circuit is not designed to drive headphones of any kind--only
line-level inputs, so that is how you should be doing all your
testing. Old amplified stereo speakers are about $5 at most thrift
stores, and will work fine for testing.

> Is it possible that though the card is outputting whitenoise that
> certain speakers/headphones will take out the white noise?

It is possible that the headphones are causing the driving opamp to
oscillate, and that is showing up as increased noise.

(BTW, after looking at your circuit, I see that you already have
a 2-pole active low-pass filter--the first op amp in each channel,
so don't worry about my previous low-pass comments.)

I expect that everything is going to work fine as soon as you
connect the board to line-level inputs.

Drew

unread,
Nov 24, 2009, 3:27:39 PM11/24/09
to

Hi Michael,

Again thanks for your help :). I just bought a pair of powered
speakers from local supermarket and sounds much better, so much so
that i don't think there is a problem. In fact there is less white
noise than on my audio animator...which i was surprised to see..or
hear rather.

I think the headphones as you said were causing increased noise.

I think the problem is that i am a bit of a perfectionist and also
didn't want people buying the cards to be disappointed.

I would like to make a review board up with one of the remaining cards
(have some things to sort out first though for connectors and it wont
have a back plate at this point) and possible get it sent to someone
to play/test with and give me their opinion and possible compare it to
other cards to see if all is as it should be. If anyone is interested
in doing this drop me a message. I would like the card back, but if
you like it i am sure we can negotiate on the cost if you want to keep
the card (and I will send back plate once i complete them...though
assuming i don't get distracted with integrating a digitiser to
it...lol)

Thanks
Drew

Drew

unread,
Nov 24, 2009, 4:32:57 PM11/24/09
to

Request for testing of review card has been accepted.

Drew

unread,
Dec 4, 2009, 10:53:27 AM12/4/09
to
Hi,

Now that the prototype all works and before i get distracted with
dealing with adding input as well as looking at making a card to go
into the portable GS that is being put together i am thinking of doing
a small run of the version 1.0 card as detailed on my blog
(drewbiegs.blogspot.com and www.drew2gs.com).

Minimum order from the PCB company is 15 cards (well 17 but will keep
a couple spare). If there is enough interest on here to get 15 cards
made I will do a small run. The card will be as pictured on the site
but will have a back plate (just waiting for the metal fabricator to
send me samples).

Cost wise i think i can do it for about £30 + shipping. I think this
translates to $49 + shipping at current exchange rate. This is not a
profit excercise for me.

I have a test card with Antoine at the moment, so wont send any out
until he comes back and says oui :)

If you are interested then please send me an email and when i have 15
people will get them produced. I will have to put them all together,
so you might have to wait a bit.

The cards themselves also have the potential to be slotless as I have
placed mounting holes and a jumper for +5v and -5v to be taken off
somewhere else apart from the A2 slot. Get a box made is on my list,
but included that in the original card design so there options

Regards
Drew

Polymorph

unread,
Dec 4, 2009, 10:09:06 PM12/4/09
to Drew
To: Drew
Drew wrote:

> If you are interested then please send me an email and when i have 15
> people will get them produced. I will have to put them all together,
> so you might have to wait a bit.

Hi Drew,

Would you be interested in supplying a cheaper "kit version" in which
you just ship the components and let the buyer assemble?

Cheers,
Mike

Drew

unread,
Dec 5, 2009, 4:35:05 AM12/5/09
to
On 5 Dec, 03:09, "Polymorph" <polymo...@a2central.com.remove-cdq-this>
wrote:

Hi,

I was thinking about doing that yesterday. I am not adding anything by
making them up. I need to go back to my spreadsheet to work out costs
for stuff to see if i can reduce the cost. The conversion rate for US/
GB isn't great so though £30 sounds alright to me from UK point of
view but US$50 prolly sounds a lot elsewhere.

Drew

Drew

unread,
Dec 7, 2009, 1:27:20 PM12/7/09
to
On 5 Dec, 03:09, "Polymorph" <polymo...@a2central.com.remove-cdq-this>
wrote:

Hi Mike did you get my emails?

Drew

Polymorph

unread,
Dec 7, 2009, 5:07:28 PM12/7/09
to

Drew,

I got an email on my a2central account (which I *never* read BTW), but
it didn't seem to want to display correctly (there was no content in
the email).

Please resend to mike dot a dot stephens AT gmail dot com (obviously
cleaning up the obfuscation!).

Cheers,
Mike

sfahey

unread,
Dec 7, 2009, 5:32:05 PM12/7/09
to Polymorph
To: Polymorph

Re: Re: Apple IIGS Stereo Sound Card - Interest?
By: Polymorph to comp.sys.apple2 on Mon Dec 07 2009 02:07 pm


> I got an email on my a2central account (which I *never* read BTW), but
> it didn't seem to want to display correctly (there was no content in
> the email).

Was that while using the HTML side?

Sean Fahey
www.a2central.com
bbs.a2central.com

Saint Isadore Patron Saint of the Internet

unread,
Dec 7, 2009, 6:33:27 PM12/7/09
to

Lots of sound programs and info on my old website.

http://apple2.org.za/gswv/USA2WUG/

Check it all out if you care to and the A2.2000.EZine collection
may also have info etc. of interest to your efforts.

Also http://apple2.org.za/gswv/

has a lot of info and programs on stereo in/out sound, music, etc.
stuff.

Cheers!
Tom

Polymorph

unread,
Dec 8, 2009, 12:36:34 AM12/8/09
to
On Dec 8, 9:32 am, "sfahey" <sfa...@a2central.com.remove-99j-this>
wrote:

Yeah, I tried viewing the email via the HTML interface. Is this a
known issue? As I mentioned, I don't really use this email account,
but I do use a2central as my news server (which I guess is why my
email is being listed as the a2central one).

Cheers,
Mike

sfahey

unread,
Dec 8, 2009, 9:51:08 AM12/8/09
to Polymorph
To: Polymorph
Re: Re: Apple IIGS Stereo Sound Card - Interest?
By: Polymorph to comp.sys.apple2 on Mon Dec 07 2009 09:36 pm


> Yeah, I tried viewing the email via the HTML interface. Is this a
> known issue? As I mentioned, I don't really use this email account,
> but I do use a2central as my news server (which I guess is why my
> email is being listed as the a2central

Yeah, it's a known issue. The BBS tries to be cute about converting the
content to ANSI (showing it's BBS roots). If people use plain text for
e-mail, it seems to work fine, but HTML formatted e-mails are hit and more
often miss.

I don't know if it's going to be fixed in the upcoming release or not. I'll
be upgrading the software and the server hardware when it does come out.

I've also considered dropping the HTML side entirely. It's funky and ugly.

Sean Fahey
www.a2central.com
bbs.a2central.com

D Finnigan

unread,
Dec 8, 2009, 11:14:42 AM12/8/09
to
sfahey wrote:
> To: Polymorph
> Re: Re: Apple IIGS Stereo Sound Card - Interest?
> By: Polymorph to comp.sys.apple2 on Mon Dec 07 2009 09:36 pm
>
>
> > Yeah, I tried viewing the email via the HTML interface. Is this a
> > known issue? As I mentioned, I don't really use this email account,
> > but I do use a2central as my news server (which I guess is why my
> > email is being listed as the a2central
>
> Yeah, it's a known issue. The BBS tries to be cute about converting the
> content to ANSI (showing it's BBS roots). If people use plain text for
> e-mail, it seems to work fine, but HTML formatted e-mails are hit and more
> often miss.
>

Or better yet, tell people to stop sending HTML emails. I have a regular
full-fledged webmail and even I find them annoying, with their insipid
colors and stupid fonts and ridiculous point sizes.

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