VOGONS


OPL2LPT

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Reply 360 of 566, by jaZz_KCS

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derSammler wrote:
noop wrote:

Also, the output seems to be quite noisy if powered via USB. Is that normal?

Most likely due to ripple pickup. Had that too. Better connect a power bank or a separate USB power supply.

Also if you encounter weird sounds, try hitting the "reset" button on the device close to the parallel connector.
Sometimes after booting and/or connecting the power source there are interferences, especially when powering from the same machine. Try using the reset button (on the OPL2LPT) when everything is running.

Also my chip is working and has yellowish text markings as well. Maybe the white one is a plagiate ?

Reply 361 of 566, by dJOS

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noop wrote:

Also, the output seems to be quite noisy if powered via USB. Is that normal?

Get a decent quality USB power brick like a genuine Apple unit, they are very low noise and produce very clean sound.

The impossible often has a kind of integrity which the merely improbable lacks.

Reply 362 of 566, by derSammler

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Really? Looking at the reviews at e.g. Amazon, they don't be that good. Not for the price Apple asks for them anyway. Any cheap one for 5 bucks will do, as all that matters here is not having common ground with the PC the OPL2LPT is connected to.

ps: you may edit your post and correct spelling, as you literally say that the Apple USB power brick produces very clean sound. I don't think that's what you wanted to say. 😉

Reply 363 of 566, by dJOS

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derSammler wrote:

Really? Looking at the reviews at e.g. Amazon, they don't be that good. Not for the price Apple asks for anyway.

ps: you may edit your post and correct spelling, as you literally say that the Apple USB power brick produces very clean sound. I don't think that's what you wanted to say. 😉

The electronic engineers I know all rate the Apple design as not skimping on quality. I'm mainly referring to older style larger heavy units, not the newer super small ones as TBH I haven't investigated those.

P.s. If you read my comment in context its meaning is clear.

The impossible often has a kind of integrity which the merely improbable lacks.

Reply 364 of 566, by noop

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derSammler wrote:
noop wrote:

Also, the output seems to be quite noisy if powered via USB. Is that normal?

Most likely due to ripple pickup. Had that too. Better connect a power bank or a separate USB power supply.

Actually, the greatest amount of the noise was only generated before the initialization of OPL2 chip by a software (not by test app, which is rather rudimentary), or when headphones were connected. When connected to external audio interface, and initialized by an app through the Adlib emulator, noise levels are ok, lower than quantization noises from Yamaha DAC.
Honestly, I doubt headphone amp was necessary at all, considering how badly it sounds on my 32 Ohm Sony earplugs (powering headphone amps from noisy 5V source is a serious challenge and LM386/LM358 are not exactly Hi-Fi parts).
But overall, I'm very satisfied. Just wish I hadn't spent many hours trying to debug various problems caused by broken YM3812 chip.

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Reply 365 of 566, by noop

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dJOS wrote:
noop wrote:

Also, the output seems to be quite noisy if powered via USB. Is that normal?

Get a decent quality USB power brick like a genuine Apple unit, they are very low noise and produce very clean sound.

I used iPad 10W PSU, except it could actually be a counterfeit. I have two of those and to find which one is genuine you need a magnifying glass. The fake one is not bad though, but the maximum current is slightly lower. Too bad my genuine Apple cables and adapters are gradually getting lost (or even stolen) and they are too expensive to buy separately. Knockoff ones can be hilariously bad. "Amazon basic" stuff seem to be ok though.

Reply 366 of 566, by dreamblaster

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hi,
if you think some chip is broken, just pm me with your address
I will send you a new one
no problem

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 367 of 566, by Megadisk

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Is the OPL2LPT supposed to be somewhat quiet? For example, no matter if I turn the board volume pot all the way, when using external speakers they have to be amplified otherwise the sound is almost non-existent.

Reply 368 of 566, by dreamblaster

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the OPL2LPT output is basically a line out, so you need amplified speakers.
You can also connect headphones, with my sennheiser hd555 it sound great.
This is not intended to connect speakers directly without amplification

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 370 of 566, by noop

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dreamblaster wrote:
hi, if you think some chip is broken, just pm me with your address I will send you a new one no problem […]
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hi,
if you think some chip is broken, just pm me with your address
I will send you a new one
no problem

Okay, just wanted to hear some advice, in the case anybody else encountered this. I'll probably also make a post with photos and recordings.
Maybe I could damage it with static, but did the testing like described, without the chip first and only inserted it at the last moment.
It sometimes produces a bunch of noises almost at random, wasn't working on one of my laptops regardless of port settings and only played a few notes before fading to silence on another system(neded reset to work again). Just replacing it fixed all the problems.

Reply 371 of 566, by dreamblaster

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the OPL2LPT 3d printed COLOR cases arrived, they look and feel beautiful !!

opl2lpt.jpg
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I received some requests to print for you too.
If you are interested, you can pm me, and I will have them printed for you, and will include the matching nuts and bolts (this is M2.5)
15 euro for the multicolor version.
12 euro for the single color version.
6 euro shipping (you can combine with other items from serdashop.com, just pm me).

Please let me know before january 26th, I will then order the new prints (also for myself).

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 372 of 566, by dJOS

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noop wrote:
dJOS wrote:
noop wrote:

Also, the output seems to be quite noisy if powered via USB. Is that normal?

Get a decent quality USB power brick like a genuine Apple unit, they are very low noise and produce very clean sound.

I used iPad 10W PSU, except it could actually be a counterfeit. I have two of those and to find which one is genuine you need a magnifying glass. The fake one is not bad though, but the maximum current is slightly lower. Too bad my genuine Apple cables and adapters are gradually getting lost (or even stolen) and they are too expensive to buy separately. Knockoff ones can be hilariously bad. "Amazon basic" stuff seem to be ok though.

If I get a chance I'll fire up my oscilloscope and capture some traces from a compact Apple brick and the older largerApple brick.

The impossible often has a kind of integrity which the merely improbable lacks.

Reply 374 of 566, by dreamblaster

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derSammler wrote:

Got my case today. Had to modify it a bit, as the volume knob did not fit, but it's fine otherwise. 😀

is that glow in the dark plastic ?

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 376 of 566, by dreamblaster

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derSammler wrote:

No, but slighly transparent so the LED will make it glow quite nicely.

nice!

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 377 of 566, by dreamblaster

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here's the STL file for the OPL2LPT with text logo on it.

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Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !

Reply 378 of 566, by datajake1999

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Will the OPL2LPT work on a modern computer with a parallel port? If so, how can I test the device on a modern version of windows?
I am planning to get a parallel port add-on card for my custom built PC, so I want to know if the OPL2LPT works on modern systems before I buy anything.

Reply 379 of 566, by dreamblaster

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datajake1999 wrote:

Will the OPL2LPT work on a modern computer with a parallel port? If so, how can I test the device on a modern version of windows?
I am planning to get a parallel port add-on card for my custom built PC, so I want to know if the OPL2LPT works on modern systems before I buy anything.

Yes, that can work, there are several possibilities :
I am running this on a corei7 with pci express parallel port card, running dos in virtual box : download/file.php?id=41049
Scali hacked dosbox to make it work (see earlier in this thread)
and finally Phil just ran it with straight hardcore on DOS on a core i7 : https://youtu.be/iPVqAvgGbWo

Visit http://www.serdashop.com for retro sound cards, video converters, ...
DreamBlaster X2, S2, S2P, HDD Clicker, ... many projects !
New X2GS SE & X16GS sound card : https://www.serdashop.com/X2GS-SE ,
Thanks for your support !