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davewantsmoore

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About davewantsmoore

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    Log! It's big, it's heavy, it's wood.
  • Birthday October 16

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    Hobart
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  1. USB cable build

    No, it's the impedance of each pin which should be terminated to 90o.
  2. Deep End DIY - My first speaker project

    Understood - I did not say, or mean to infer that there was any smoothing involved.... I am talking about the frequency resolution (the number of data points per Hz). Higher would show the dips more accurately. The SPL measurement error is potentially a consideration. <0.5db can be measurement error (it's worth investigating in your setup, anyways). The higher damping of the driver looks good, although it's good to begin without these issues (and not having mechanical damping added to remove them). Point being. I wouldn't stress too much about this. More importantly is the implementation of the filters to achieve the crossover, and how the driver and summed responses look in the listening position, and all that.
  3. What are the best RIAA capacitors?

    The best capacitor is no capacitor
  4. Deep End DIY - My first speaker project

    Some may be tempted to dismiss this as semantics, but these are not peaks. They're cancallations (at ~210Hz and its harmonics). If you had a higher frequency resolution, you could see they extend much lower (in theory, to zero - representing a complete interference cancellation). I would surmise they are larger in the gold line becuase this stuffing is less absorbent than the other type of stuff (?!). In a super-high performance system they are definitely worth considering .... although the dB scale belies their size
  5. Deep End DIY - My first speaker project

    Check the ohm scale on his chart and your chart There is no more energy. It is just the dimensions wrt to the wavelengths. Looks to be like a filter with ~6dB/octave attenuation in the passband will do the trick well to EQ the driver ... as for the "crossover", you'll need to see your next driver up before you can think about that.
  6. Deep End DIY - My first speaker project

    You should choose a frequency where you know that each have the same output (low frequency). Doing it at 100Hz makes the chart v.difficult to interpret.
  7. Deep End DIY - My first speaker project

    Yeah, sounds like go lower in density. Something around 10kg/m^3 The shape of your enclosure becomes relevant as you go up to non-subwoofer frequencies .... and the enclosure is a bad shape. So it will be a battle. Align them at the lowest frequencies. (Hint: It didn't give you more bass output) I don't really see how a port will solve any of the wiggles being discussed here (like you say, it's the shape of the enclosure) ..... I see the merits of ports being only where you absolutely need the extra efficiency gain. This system absolutely doesn't with 16 drivers planned. Nah. If you were going to move to a BR design, then it would be important to actually design a properly working port. Simply opening the back would make it a dipole, which would mean less bass .... and a dipole peak to worry about - the two way that is deal with are, either EQ (incompatible with Ant goal), and not using the enclosure above that dipole peak frequency (also incompatible with Ant goal).
  8. Hobart GTG late september EOI

    Put me on the list. I'll have to confirm closer to the time
  9. Deep End DIY - My first speaker project

    I don't know what type of stuffing you used (sorry if I missed that post) Seems like it might be quite dense? (EDIT: I just caught up, and it seems you confirmed that) You really do want to get all the 'unpexedcted wiggles' out of the impedance curve of a driver. I wouldn't bother too much with listening tests as they really don't provide reliable information for a number of reasons. Aside from that, you'll find that the biggest most critical aspect of the subwoofer performance is where it is placed in the room. It's not a "bad idea" .... but the question is why are you doing it? Adding large and expensive components between the driver and amp can only hurt - so what are you trying to achieve by changing the impedance seen by the amplifier? If it's "to make the crossover components work as expected" .... then you can factor the impedance trap into the crossover design ..... I'd be a bit anti passive speaker level filters at these frequencies regardless though. That's a generalisation based on typical value amplifiers which aren't designed for low impedances.
  10. F1 2017

    You really seem to be mixing up the roles of the stewards and the FIA judiciary. Vettel action (steering in to another car, when there was no corner or other reason) was very dangerous. The stewards made the correct call IMHO. Whether he meant to do it, or not .... was not considered as a factor, as it could not be under the rules of F1. It's very simple.
  11. F1 2017

    Those types of incidents are typically 'racing incidents' as nobody could realistically see them coming, or have enough time to do anything to avoid, etc. Eg. two cars ending up trying to share the same piece of track, due to decision made by both drivers. Seb OTOH, steered into someone dangerously. He should have known it was dangerous, and he shouldn't have DONE it. See here how whether he actually MEANT to steer in, isn't a factor in anything. He doesn't get to claim "oh it was an accident" as a defence.... and others don't get to claim "he did it on purpose" as strengthening the penalty. That's how the rules of the sport work. Yes, the difference between dangerous and deliberate could be seen as semantic, or pedantic ..... but, that's how rules work. If you're making the claim that the stewards used some other rule book to adjudicate this incident ..... then you've got a long hill to climb. If you're just trying to push the point that you think that Seb did it on purpose ..... then sure. I reckon there's a real majority of people out there who would agree with that on some level. OTOH, a FIA tribuneral (if convened, which they've chosen not to) .... would be allowed to take all sorts of things into account. They could look at the telemetry and say "we think you did this on purpose" ..... and they could use what he said after the race regarding the incident, as a factor, etc. etc.
  12. F1 2017

    Oh, I see. It's pretty hard to be conclusive about that, of course .... but the steering in looked to be a deliberate action. Was making contact deliberate? Who knows? It would be surprising to me either way .... if contact was a mistake (a mistake of this nature is surprising to me), or if deliberate (he shouldn't be this silly). Anyways.... my only point was that talk of stewards and deliberate in same sentence is nonsense - becuase it makes no difference. Any claim otherwise is to claim stewards did no adjudicate within the rules.... which is a super bold claim. Are you making that claim? I would have like to see the FIA refer it to the judges for a hearing later on (even if the judges rule he doesn't need a sanction) .... to simply let it go looks bad IMO.
  13. F1 2017

    No it isn't. Just repeating it and repeating it doesn't make it so. The RULES don't work like that. So if it was like you say, then they all should be sacked..... It was judged on how dangerous it was, becuase that is what the rules say. Yes, poorish choice of wording on my part.... the FIA looked at it (as they do everything), and decided that no further action was required. No further action being charges, and trial with FIA judges, etc. (ie. a big arsed investigation into vettels 'behaviour').
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