ckrtech Posted November 27, 2017 Share Posted November 27, 2017 Hey guys - Made an S-Video cable for my system, and the audio seems a bit loud overall. Is the sound line level at the DIN output? Quote Link to comment Share on other sites More sharing options...
sup8pdct Posted November 27, 2017 Share Posted November 27, 2017 Supposed to be 75 ohm resister on main board but i dont think it is. Wouldn't worry about it to much tho. James Quote Link to comment Share on other sites More sharing options...
TheTIGuy Posted November 27, 2017 Share Posted November 27, 2017 (edited) "I'm sorry; the number you have reached is not in service, or temporarily disconnected. The number you have reached is not in service at this time. This is a recording." Edited November 27, 2017 by TheTIGuy Quote Link to comment Share on other sites More sharing options...
1050 Posted November 28, 2017 Share Posted November 28, 2017 If you mean designed to be in compliance with other audio devices that use standardized line level inputs and outputs, then probably not even a consideration done by Atari. So just attenuate it to your liking and then it will be. Just guessing here but maybe try 500 ohm shunt to ground and if still too loud then lower the ohm rating for the next attempt. Exact ohm rating won't usually be in decades so just something close that's available to you would work. 470 ohm for example would be a fine place to start with. https://www.amazon.com/Decade-Resistance-Box/dp/B00ALLDB86 One of these decade boxes would help find the proper resistance a bit faster? I got mine off eBay a long time ago for a little less but they are not there anymore and the atlanta-robotics site seems to be offline so there may be a chance that the cheap way can't even be had anymore. Resistor substitution box is another search term to use if this method appeals to you over just pick one and try it method. IIRC line level is standardized to be 600 ohm impedance so 75 ohm attempt by Atari shows the level of detail that made it to the design board - in other words nada. They didn't care enough to even look it up. More foggy recollections 1 V maximum peak to peak at 600 ohms? Quote Link to comment Share on other sites More sharing options...
ckrtech Posted November 29, 2017 Author Share Posted November 29, 2017 Hmm. Interesting. I have an audio switchbox (homemade) to switch between two inputs (normally two modern computers) as well as two outputs (computer speakers and 64ohm headphones). The Atari seems a bit hot as barely a small increase in volume from 0 results in a rather sudden "appearance" of boomy sound. So, I figured the Atari output its audio with a bit more oomph - possibly due to the hardware (built-in speakers in a monitor?) of the time. IIRC line level is standardized to be 600 ohm impedanceso 75 ohm attempt by Atari shows the level of detailthat made it to the design board - in other words nada.They didn't care enough to even look it up. More foggyrecollections 1 V maximum peak to peak at 600 ohms? And that 75 ohm resistor was apparently supposed to be on the main board but isn't if I am properly reading what sup8pdct wrote. I suppose I could look into generating a tone from the Atari and hook it up to an oscilloscope, etc., etc., (would be my first time messing with sound on a scope, actually)., but I am more likely to throw some resistance at it. I thought perhaps some of the Atari mod guys might know the proper/relative values offhand. Quote Link to comment Share on other sites More sharing options...
1050 Posted November 29, 2017 Share Posted November 29, 2017 Hmm. Interesting. Uh huh (the hell you say, tee he he he) I have an audio switchbox (homemade) to switch between two inputs (normally two modern computers) as well as two outputs (computer speakers and 64ohm headphones). The Atari seems a bit hot as barely a small increase in volume from 0 results in a rather sudden "appearance" of boomy sound. Can we be sure that the sudden appearance of boom isn't due to Fletcher Munson curves designed into your rendering equipment though? Just a possibility I'm throwing in the air to see if you'll shoot at it or not. In my experience they shouldn't have made the Fletcher Munson volume control as set by some arbitrary tap point because it's wrong where it's placed and it's not adjustable when it needs to be. Needs both amount of boost applied and where to apply it. First one is simple, another volume control added, the second issue will never be as easily solved as the first. I'm constantly needing to tweak mine depending on the source and even content, so I assume 'engineers' are tweaking it before it's even laid down for my consumption too. The result can then only be crazy making for the consumer. So, I figured the Atari output its audio with a bit more oomph - possibly due to the hardware (built-in speakers in a monitor?) of the time. And that 75 ohm resistor was apparently supposed to be on the main board but isn't if I am properly reading what sup8pdct wrote. Negative on the first one would be my stance, we are lucky they put in composite video out and I've never had a religious experience rocking to the tunes on a color TV that was most of the time the viewer for Atari back in the day. I do remember the experience of 'stereo' as implemented by TVs back in the day, their artificially recreated right channel seemed to come from about 30 feet away which cause me to holler at the cat to get off the counter so many times when the cat was somewhere else entirely. Poor cat had to live with insane people yelling at her for things she wasn't doing. No wonder she never paid us much attention. Can't know because I'm not him, but I'm assuming he was thinking about the RF side where audio is combined with the video signal coming out. That's a wrong design point issue too, but not this one. Looking it up myself just now to know what line level actually is shows several opinions on the subject with the main takeaway being that it's not a matched system as RF lines should be, but the mismatch is there on purpose to maintain fidelity as the primary issue. Output around 100 ohm, input around 1K ohm with no spec talked about as to voltage level but I have seen 1 volt listed on the back of a Sony minidisc player/recorder for example. They did mention 600 ohms but that was the first thing tossed into the hamper after they stuck a knife into matching lines are required for audio frequencies deal. Lot of murder and mayhem in general and no small small amount of conflicting opinions too. I suppose I could look into generating a tone from the Atari and hook it up to an oscilloscope, etc., etc., (would be my first time messing with sound on a scope, actually)., but I am more likely to throw some resistance at it. I thought perhaps some of the Atari mod guys might know the proper/relative values offhand. You are the very first by my count to even approach the Line Level subject from an audiophile's viewpoint. I would expect the output to vary from machine to machine so much that you'll need to cook up another matching network for every one have in your stable too. I've taken to calling my homemade A-B switch, a breakout box because it has so many talents. But they used to be called A-B switches where you only had two choices of two inputs A or B and a single output. Mine is still single output but does have a return loop using the front to back fader so that I can boost a weak source if need be. Recording jacks on all inputs with a chicken head four channel selector on one side and TV input on the other. Has simplified my life by a vast amount where I used to have to find and untangle all those lines to hook them up manually. Jeebus, what a Godsend. Knowing what I know about it, throwing some resistors at it is by far the better way to go and don't be surprised when you need to throw some more at it later either. Quote Link to comment Share on other sites More sharing options...
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