The normal unamplified Line Out of the CT2860 is noticable more noisy then that of the CT2800.
I found that the raw output lines of the CT2860 Vibra chipset go tot a 8 leg TDA8199 chip. Which is told to be a "Stereo Amplifier And DC Volume Control For TV". This chip is not found on the CT2800.
I don't know yet if this thing is always between the line-out of the CT2860, but if so it would mean there is no pure Line Out on this card. But either single or double Amplified.. That is bad. The TDA8199 has a volume control input which is routed to a pin on the Jumper block J5 nearest C93...

The sticker on the back of this card says this card is a HP part, as in Hewlett Packard maybe.

Edit: I traced the amplified output, pretty sure it is going through both amplifiers, so double the noise.
Also I traced the Line Out, it is going through the small amplifier too.

gerwin wrote:

The normal unamplified Line Out of the CT2860 is noticable more noisy then that of the CT2800. I found that the raw output line […]
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The normal unamplified Line Out of the CT2860 is noticable more noisy then that of the CT2800.
I found that the raw output lines of the CT2860 Vibra chipset go tot a 8 leg TDA8199 chip. Which is told to be a "Stereo Amplifier And DC Volume Control For TV". This chip is not found on the CT2800.
I don't know yet if this thing is always between the line-out of the CT2860, but if so it would mean there is no pure Line Out on this card. But either single or double Amplified.. That is bad. The TDA8199 has a volume control input which is routed to a pin on the Jumper block J5 nearest C93...

The sticker on the back of this card says this card is a HP part, as in Hewlett Packard maybe.

Edit: I traced the amplified output, pretty sure it is going through both amplifiers, so double the noise.

Can you bypass it?

sliderider wrote:

Can you bypass it?

Yes I tried that. First by cutting the power to the first Amp. But after that I decided to totally remove the first Amp from the card. Either way the noise was much less and the card still works.

Still it gives a bit more 'computer' noises then the CT2800. So I will try to bridge it better.

The way it is now the noise floors of both cards are the same. 😀
Except there is one problem remaining with the CT2860: When an effect is played sometimes a slight ringing sound remains afterwards. Audible when setting the volume loud. The ringing can only be stopped by playing another sound.

I don't know how to improve on this.

I give up on this one, The random high pitch ringing is coming from the Vibra 16S chip itself. So maybe another CT2860 can easily be fixed, but not this one.

Attached an image of the jumper block present on another HP card (CT2970). It is similar to the CT2860 jumper block. It is for a front panel connector.

I have two CT2860 cards, and both of them have a pretty audible level of noise.

Mau1wurf1977 wrote:

I have two CT2860 cards, and both of them have a pretty audible level of noise.

Yes, I actually borrowed the photo that you made of the card for this topic.

gerwin wrote:

I give up on this one, The random high pitch ringing is coming from the Vibra 16S chip itself. So maybe another CT2860 can easily be fixed, but not this one.

Hmm the CT2800 sometimes has this problem too. I hear high pitch noises after digital samples are played in certain games: Comanche to some extend, but more obviously in Star Control 1 and Tyrian.

Edit: maybe it is because these games detect the wrong IRQ

Edit2: With Star control 1 it was General Midi making the noise. Tyrian remains quite troublesome with the Vibra16 (at IRQ 7): instant high pitch whistles.
The CT2800 actually has the same high pitch whistles problem as the CT2860, but so far I noticed it a little less on the CT2800. As tested with System Shock.

So I tested it again today and I fear I must conclude the following.

The AWE 64 (Gold) Card has no problem playing digital samples. (has someone ever gotten this thing on IRQ7 though?)

The praised SB Vibra 16S (CT2800, CT2860 etc) actually has two hanging note problems: the well known problem with the General Midi interface and a less obvious hanging note problem when playing digital effects.
After a sample is played, at random there is a chance of a high pitch whistle. This noise can be heard with headphones. It is not loud. It remains until a new sample is played. The noise originates from the unamplified Voice/Digital effects channel.
The most effected game is Tyrian, which is not enjoyable for me this way, but it also includes the Miles driver games such as System Shock. These other games I played for long without noticing the issue.

I've played Tyrian on my CT2800 and I don't remember having this problem. I'd sometimes get a stuck note after exiting a game but I'd never notice one during - unless I was using General MIDI.
I don't have the CT2800 in my 486 any more so I can't test it right now but has anyone else noticed this?

gerwin wrote:

The AWE 64 (Gold) Card has no problem playing digital samples. (has someone ever gotten this thing on IRQ7 though?)

Yes, but I had to disable the parallel port in the BIOS. Otherwise it detects it and won't allow you to set IRQ7.

CTCU that is...

but why would anyone want to use IRQ7 anyway?

I believe that there are certain games that are hard coded to use IRQ7 as that was the default IRQ for Sound Blasters prior to SB16. I can't think of any of the top of my head though. The vast majority would let you pick and choose in their setup or just check the BLASTER variable.

Its also possible that you want multiple sound cards in the same machine especially if you are playing with GM devices. So you'd njeed to juggle IRQs, IO ports and DMA's.

IRQ 7 is the classic Soundblaster standard, later it was changed to 5 because of the printer using 7 too. I stuck to 7 somehow.

Mau1wurf1977 wrote:

CTCU that is...

CTCU requires dos 6.22 or lower, I need a bootdisk. Does CTCU just edit ctpnp.cfg or does it write to an EEPROM on the card? I can edit ctpnp.cfg myself, but it does not make a difference.

I was being silly, the Printer port was still on IRQ 7. Now I disabled the printer port and reserved IRQ 5 for legacy ISA, the AWE64 moves to IRQ 7. I now use CTCM with the /T paramater to initialize it in DOS 7.10.

In my retro system I now have these soundcards Installed.
- AWE64Gold for Digital/Voice (and the EMU synth as a bonus)
- Vibra 16S for OPL3 and the waveblaster header and for mixing all sound sources, including the PC speaker.
- Roland MPU-401AT card
- Midi Daughterboard on Vibra's header with stereo reverser and midi-input pin bypassed to the Roland card.

Reasons:
- AWE64 FM music is based on the undesired CQM.
- Vibra 16S Digital/Voice has a whistle problem.
- MPU on the AWE64 works horribly with TIE fighter Collectors CD?
- I cannot initialize the MPU on the Vibra when the AWE64 is installed.
- Almost all daughterboard host cards (including the Roland, excluding the Vibra) "clip" the analog output of my favorite daughterboard, to a certain degree.
- I wanted to use the AWE64 card as the mixer, but somehow the music did not come out enjoyable, maybe the bass/treble settings were acting up.

All three ISA slots occupied and the DB sticking out on top. Well I am both satisfied that it works 100% now, but I am also a bit disappointed at all the hardware required to get this error-free sound functionality, the way DosBox does. Well almost, because there is no proper SBPro compatibility with the above setup, just SB and SB16. The noice floor is acceptable now, not good but fair. Tested game compatibility so far is 100% 😀.

Next week I am gonna put in a CMI8330 soundcard on its own, and see how it compares.

no offense, but I personally think the endeavor to get an AWE64 to work in IRQ 7 is pointless and silly... if you have any of the old 1989ish games that needs IRQ 7, it'll probably not even work right with that system anyway because it's much faster... making IRQ 7 "compatibility" a moot point

TheMAN wrote:

no offense, but I personally think the endeavor to get an AWE64 to work in IRQ 7 is pointless and silly... if you have any of the old 1989ish games that needs IRQ 7, it'll probably not even work right with that system anyway because it's much faster... making IRQ 7 "compatibility" a moot point

Not true. Later systems can be "downclocked" so they run at a speed acceptable for older games. In that case, putting the AWE64 on IRQ7 may have some value.

Well I is not that I advise other people to go to IRQ 7, it is merely that all DOS games here are tested and pre-configured for 7, and zipped up like that too. And I don't feel like changing that to 5 because of a soundcard being stubborn.

This system is running at 150MHz by default, and I use Throttle as a slowdown tool.

are these dutch games or the US made games that were famous around the world?
just wondering because I NEVER had any issues with old games working with IRQ 5 with my SB16, or even my AWE32... neither one were PnP though... this was way back in the 90s, not in any recent years... my retrobox still hasn't been resurrected yet.... hardware all intact and working, but OS be broke! 🤣 yes, I'm so lazy 😁
the oldest games I played were from 1991, so....

TheMAN wrote:

are these dutch games or the US made games that were famous around the world?
just wondering because I NEVER had any issues with old games working with IRQ 5 with my SB16, or even my AWE32... neither one were PnP though... this was way back in the 90s, not in any recent years... my retrobox still hasn't been resurrected yet.... hardware all intact and working, but OS be broke! 🤣 yes, I'm so lazy 😁
the oldest games I played were from 1991, so....

He does mention the use of zip files, which might indicate he stored digital copies that way