almikel

Members
  • Content count

    1,732
  • Joined

  • Last visited

About almikel

  • Rank
    Member

Uncategorized

  • Location
    Brisbane
  • Country
    Australia
  • First Name
    Mike

Display Name History

  1. Hi Jimmy, I'll likely get flamed, but bias will always impact this sort of test. To provide a similar example, I downloaded the same track in 3 different formats, 320 MP3, 16 bit 44.1, and 24 bit 96K. I listened to them over and over and heard a major difference, especially between MP3 and 24/96, and was gobsmacked my friends couldn't hear the same difference - until I handed them the remote. I was unable to reliably tell the difference when they changed the format. I'm not saying there wasn't a difference between your Hugo and the iPhone, just that bias has a big impact on results. cheers mike
  2. You didn't add the to that post - scanned a few posts and noticed Zaphod's post a page back on DACS, so I assume you meant, "DACs likely make a difference, but it could be chasing the last few %"?? Everything obviously makes a difference, including amps, but in my experience things that process/convert audio (eg turntables/ADCs/DACs/Speakers) have more chance of negatively impacting the sound. This basically covers "transducers" that convert a signal from 1 form to another, including the digital/analog conversion even though it remains an electrical signal. IMHO the ADC/DAC process is harder to implement well compared to amplification...I'm not saying good amplification is trivial though! More important is the Speaker/Headphone transducer trying to process an electrical signal into an acoustic output...and the room of course, but that doesn't apply to Cans. I'm sure under critical listening conditions you can hear differences between well designed amps - which is "better" will be subjective. In my particular audio journey I've built my system around "reasonable" electronics with more focus on the speakers and the room. I don't have much experience with headphones, but with speakers in a room, IMHO placement/treatment and EQ will affect the "in room" sound way more profoundly than the amp, assuming the amp is well designed and operating within its limitations. cheers Mke
  3. Aechmea has said it numerous times before, and I agree - Speaker Boundary Interference Response (SBIR) is often a bigger issue than modal behaviour. this advice will help to identify if that dip is room or position related (ie modal or SBIR), or something else (eg crossover). For mid-bass drivers I like to keep them close to the floor to avoid "ground bounce" SBIR issues, but subs go where they need to go to achieve the best room response. Ken Tripp (a member here on SNA) has a great SBIR calculator http://tripp.com.au/sbir.htm If you move the sub around, and the frequency of the dip changes, then the dip is likely SBIR related. If the frequency stays the same, it's likely modal, unless that happens to be the Xover pt between mains and sub. I'm not familiar with the AS-EQ1 - but these days the DSP is pretty clever (mostly ) - so probably not Xover or phase related. I don't let my DEQX decide on much in the bottom end - I prefer to do a manual setup based on measurements, then measure again and tweak - but that's just me. Ignoring all of my post above, if you install superchunks in all 4 corners it will clean up the mid bass markedly and make a big difference to the "in room" sound. Below 100Hz, in my room which has a lot of absorption, I've found EQ to be very effective, as long as you're not trying to "fix" Xover/phase issues between mains and sub, or SBIR issues. Modal "peaks" below 100Hz respond very well to EQ, so do shallow dips - don't attempt to EQ deep dips. if you want to shoot for the best room response, I'd recommend the following reading: Paul Spencer's Bass integration guide part 1 of 3 linked below http://www.hifizine.com/2011/06/bass-integration-guide-part-1/ And the Acoustic Frontiers Measurement Standards Guideline http://www.acousticfrontiers.com/wp-content/uploads/2011/10/acoustic_measurement_standards.pdf Consider the Acoustic Frontiers' paper as the "Gold Standard" target - but don't get disillusioned if your room doesn't meet it - even after treatment - my room doesn't meet their spec and I've got a fair bit of treatment and EQ in a lightly constructed room. That said, the bass response in my room is better than any other space I've critically listened to (in a domestic stereo environment). Once you hear a room with the bass under control - you can't go back... ...be careful - you may find the sound in cinemas (bars/nightclubs/concerts) just doesn't cut it anymore ... ...but the upside is you can't wipe the grin off your face every time you crank the stereo in your own room! cheers Mike
  4. 600mm wide superchunks floor to ceiling in all 4 corners will make a significant difference. As mentioned above, if going with superchunks, normal fluffy batts cut into triangles 600mm wide on the hypotenuse stacked floor to ceiling will work well. That's lots of cuts to make. As much as I hate fibreglass, they will be easier to cut neatly compared with poly. That said, fluffy poly is easier to cut than Polymax XHD (and way cheaper). Buy a bag of Greenstuf Poly batts for approx $35 and try different cutting methods. A quick calc shows the sides of the right angle triangle with 600mm hypotenuse are 424mm, so the 430mm wide batts would be perfect. You can even get rolls that are 430mm wide like this http://buybuildingsupplies.com.au/r20-underfloor-insulation-116m-430mm-roll-pack-p-28424.html that link there is a minimum order though - but that was 1 Google search Mike
  5. Looks like you have 1 sub already from the frequency response Have you tried different sub positions for that suckout? Also try some phase adjustment on the sub assuming it has some. Definitely not saying don't go multiple subs - just that you may be able to get a better result with what you have now. cheers Mike
  6. I doubt such a narrow Q dip is audible (the one around 160Hz) the broad dip around 55Hz would be
  7. For anyone wondering what a "Superchunk" trap is, it's a corner straddling trap with the triangular gap behind filled in with absorption. They work very well even with fluffy insulation if large enough, as any distance off a boundary velocity is >0. Mike
  8. Hi I13, Ultratel would work fine as it's easy to cut - Polymax XHD would work fine also but way harder to cut for superchunks. Mineral Wool would work fine also, but I've never mucked with it - so I can't comment on local availability. Fluffy (ordinary thermal batts) works fine for superchunks also. Are you happy to use fibreglass and cover them? - if so then use the cheapest 'glass batts you can find. If you want to use Poly then the cheapest poly batts you can find - but as above Poly is much harder to cut. With enough of it, fluffy works at least as well or better than the "acoustic" products - it depends on how much room real estate you want to give up. There's a strong correlation between the "acoustic" properties and the heat "insulation" properties for thermal insulation products. The key metric for both is the Gas Flow Resistivity - unfortunately not usually quoted in the specs. For similarly sized superchunks (say 1m wide, floor to ceiling), I'd expect there'd be some performance advantage in using Ultratel/Polymax XHD compared with fluffy - but not much. Fluffy is way cheaper (fibreglass or poly).for superchunks. cheers Mike
  9. when applying room treatments I just ignore resonances at 50/100Hz that don't decay - they're always power supply/earth loop related, and hardest to pin down in active setups with many amps. This is a whole different topic to room treatment, but IMHO only needs to be addressed if you can hear the hum at the listening position Mike
  10. 3+3+3+2 = Scumbags amps clearly go to 11 !!!! for those that may have got confused with the maths dB = 10 log (p1/p2) 3dB is approx double the power - 10^0.3=1.995 10dB is exactly 10 x the power - 10^1=10
  11. nice result 10dB boost requires 10x more power not 4x roughly double the power for each 3dB cheers Mike
  12. In a previous era where recordings were done with minimal mikes, you got a proper sense of space and depth on a recording, and on playback could "place" a particular instrument within the sound field. With modern recordings there's a tendency to "close mike" everything, and any "image" is artificial and created by the producer using pan potting etc - an example is if your room is wide, the piano appears as wide as your room... I hate it when they close mike the piano and the low notes come from 1 speaker and the high notes the other. I would say this is less natural sounding than any EQ applied during playback. Only my opinion, but good imaging starts during the recording process, and can be wrecked way before it gets to the CD, Vinyl, or whatever medium - and the concept of a "Sound Stage", where you could close your eyes and hear the singer at the front, instruments beside and behind the singer have largely disappeared due to close miking - capturing the depth of a sound stage - placing instruments on a stage front to back, doesn't work with close miking. It hasn't been my experience that mucking with playback EQ changes left to right placement of instruments or the overall image. Not sure what you mean by degradation? - all filters have impact including linear phase filters (no free lunch) - whether it's audible is the question. Linear phase filters introduce "pre ringing" - you start to hear the drum hit before the drum hit - a non-causal effect which is quite un-natural.. Most auditory things in nature are causal - something happens and you hear it. I'm not saying linear filters are bad, just that all filters have compromises. The steeper the filter the more they ring (resonate) - for linear filters this is both pre and post ringing, for non-linear filters this is only post ringing. - the energy in the ringing will be the same for equivalent filters - just that a linear phase filter will share the energy on both sides of Time = 0, a non linear filter has all ringing energy at Time > 0 Tone controls will experience the same thing - phase impact and ringing will depend on how much EQ is applied. The ringing of any filter is best observed in the impulse response. All filters ring Linear phase filters have pre-ringing and post-ringing Non-linear phase filters only have post ringing IMHO EQ is a great tool if used well - but it's effects and limitations should be understood. Linear Phase EQ isn't better or worse than minimum phase/parametric EQ, and neither is evil, unless poorly applied. Properly applied EQ could help imaging if correcting a room issue. Mike
  13. But I would challenge that the sound engineer is closely listening to the imaging changes based on tweaks to EQ. Having sat next to a sound engineer tweaking EQ, levels, thresholds on limiters etc etc for hours ad nauseum on a single track - they're not listening for very subtle changes in imaging. Perhaps the mastering engineer on a Pink Floyd or Roger Water's album is - but they'd be deliberately adjusting imaging via more EQ/panning etc). @Zaphod Beeblebrox as you know every system has significant phase shift - especially multi way speakers with crossovers - including 1st order Xovers (1st order obviously has less phase shift, but other issues). A woofer in a sealed box has phase shift (all drivers do of course - just using the 2nd order high pass of a woofer in a sealed box as an example) . Rooms create their own phase shift. Any deviation from a flat FR has phase shift You can clearly hear changes in phase impacting imaging - but does EQ created phase shift always impact imaging negatively or is it just different? A room created peak in FR causes phase issues - and treatment only goes so far. Applying parametric EQ to pull out a room peak (assuming minimum phase) will fix amplitude and phase to align more closely with the recording. Has the EQ negatively impacted imaging? A speaker that rises in the top end (and has a corresponding phase error) that you tweak with EQ to provide a flat response - have you wrecked or fixed the imaging? The heathens that think a room curve is a good thing, and apply a curve that slowly shelves downwards from 100Hz or wherever - is their imaging destroyed? As per your maxim on priorities, "room, room, room, then speakers etc", you can never replicate what the mastering engineer was listening to in the studio. EQ changes the sound - obviously - but I haven't experienced the negative impacts on imaging that you describe. Mike
  14. different topology amps have a different Power Supply Rejection Ratio (PSRR). mike
  15. Likely power supply noise rectified to 100Hz Mike