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Everything posted by peniku8

  1. Running your amp channels in series (bridged basically) is cool and all, but does anyone have experience with running them in parallel? From a technical point of view, the amp with the higher output voltage will try to drive the amp with the lower voltage, so they should be matched as closely as possible when operating in parallel mode. To my understanding, having dissimilar voltages on a BTL setup only reduces the overall voltage swing, so we're not going at full power. In bridged mode operation, the two amps will both see half of the impedance, as voltage is doubled. In parallel mode, the amps will see double the impedance, as current is doubled, which would, for example, make driving the 1 Ohm IPAL a lot easier. Also, you could couple 4 amps like this, which would provide double voltage and double current to the loudspeaker while keeping impedance (and damping factor) the same. To go even deeper, to my knowledge the output transistors on an amplifier operate in parallel(?), so adding a second output stage might be similar to adding more transitors. Would it be possible to build an infinitely powerful amp with just adding more paralleled transitors? Crown's old Macrotech amps have a parallel feature, which expects you to run a jumper wire from 1+ to 2+ on the output side.
  2. Gotta say I'm impressed that these amps sustain more power than what they're rated for. Especially the naming scheme threw me off. Being used to other manufacturer namings I'd expect the 4-300 to burst 4x300W into 4R, but instead it does 4x400W into 8 and 4x600W into 4. The soft limiter is a nice feature for a non-dsp amp, as I think it's better than hard clipping. Gonna sell it for 250 bucks, as I have no use for it anymore. Very nice amp for the money.
  3. t.amp TSA4-300 Frequency response: Vmax(RMS): 66,9V Idle power draw: 95W Efficiency: 80% at around 500W output, gradually drops to 60% at 4KW output. Highest observed amperage readout: 17A (@230V) Mains connection is a C14, which is rated at 10A. Resettable fuse triggered during 4x8 and 4x4 tests. Long term power output tapers down to about half the numbers seen here. Amp goes into protect after about 90s during any 4 Ohm test. 4x4 triggers the fuse after 15 seconds. Fans are temperature controlled and have 2 speeds. Soft limiter is quick and reliable. Can't be bypassed. I couldn't get the amp to hard-clip, except for a few ms at the beginning of a test. Single Channel 1x8Ω - 475W @1khz 1x4Ω - 682W @1khz 1x2Ω - 278W @1khz Dual Channel 2x8Ω - 2x450W @1khz 2x4Ω - 2x698W @1khz 2x2Ω - 2x237W @1khz Quad Channel 4x8Ω - 4x392W @1khz 4x4Ω - 4x594W @1khz
  4. t.amp TSA-1400 Frequency response: Vmax(RMS): 68,9V Idle power draw: 25W Efficiency into 8R and 4R: 80-85% Efficiency into 2R: 70-75% Highest observed amperage readout: 14,8A (@232V) Mains connection is a C14, which is rated at 10A. There should be an S10 fuse inside. Started smoking 20 seconds into the 2x2 test. Test aborted, no damage. Amp is fan modded, but the part where the smoke came from is isolated from the air flow. Fans are temperature controlled and have 3 speeds. Fan speed lowers when amp is under heavy load (Voltage sag from PSU). Soft limiter is quick and reliable. Can't be bypassed. I couldn't get the amp to hard-clip, except for a few ms at the beginning of a test. Single Channel 1x8Ω - 502W @1khz 1x4Ω - 904W @1khz 1x2Ω - 1460W @1khz Dual Channel 2x8Ω - 2x463W @1khz 2x4Ω - 2x799W @1khz 2x2Ω - 2x1231W @1khz
  5. If your ports run along a side wall you can add anywhere from half to a full port width to the length. I've even had a case where I had to add 1.5x the port width to its length, but that was a spline shaped port. One of my designs has the port opening about twice its width from the rear wall. I had to add 80% of the width to get to the actual tuning in hornresp. Stuffing isn't too popular in PA subs as you might lose 1-2db. The l.acoustics KS28 for example isn't even lined with foam or anything. They have good limiters in their system amps which prevent the subs from being overdriven, so they don't really need to mask distortion near or even above Xmax, which you might reach without a properly matched dsp.
  6. You're meant to keep the port end away from the wall it is facing, which would be the rear wall in the cases you listed. Proximity to the side walls doesn't really matter. Stuffing your box reduces distortion and mechanical noise at the cost of output. Both seem to be rather small, so it's up to taste. If you have resonance issues in large back chambers, the filling can mitigate that, but you'll need a lot of it. That means in bandwidth resonances, so any dimension above 1/4 of the wavelength. That's 85cm or 2.8' at 100Hz. Keep the filling away from the port so that it can 'breathe'. Wave your fingers close to your mouth and blow. What you hear is what objects to do airflow, noise wise.
  7. I'm using a Stairville PD-332 Power Distributor, which provides me with basic voltage and current readouts. It's probably not the most accurate but it works well enough to approximate the data I'm after (idle power draw and efficiency under heavy load). Being able to check on the voltage sag is also useful. And the fact that I have the breaker right where I can reset it quickly is nice with bigger amps.
  8. Will post the results of the other amps I have soon and add other frequency tests when I have the time to do those. All test durations will now be ~12s so I have enough material for my 10 second window. The Sanway delivers solid power and I think it blowing up and tripping my 230/16 breaker constantly wouldn't have happened with actual music content. The 10KW spikes will thou. I'm not a generator expert, but I've been told it's not good for them. Anyways, next amp on the list is super famous in Germany and that for a reason as I found out.
  9. Sanway FP-13000 (MKI) Vmax(RMS): 134,9V No frequency response since it blew up. It's +-1db from 3,5Hz to 44khz. Idle power draw: 115W Efficiency at 4KW output: 78% Highest observed amperage readout: 48A (@231V) Blew up after 90 seconds of 4KW output. PSU broken, power input board damaged, internal fuses on the amp stage damaged. Soft limiter was non-functional. It just clips the waveform. VPL kicks in at 188V, hence the lower ratings into 8 and 4 Ohm. I'll check if I can adjust that internally when I manage to bring the amp back to life. Single Channel 1x8Ω - 2075W @1khz 1x4Ω - 3964W @1khz 1x2Ω - 7197W @1khz
  10. I use EqualizerAPO to calibrate systems in rooms which don‘t have outboard dsp. You can export txt files from the Equalizer in REW and import those to APO, it‘s great. I‘m running the cheapest 12“ Klipsch sub as backup subwoofer and it‘s pretty much flat in my room down to 20Hz or so. It will compress quickly, but if you only want moderate listening levels it would be fine I guess.
  11. Small update from my side: I was very eager on posting results here but the blown amp has demotivated me to the part that I went on to finish other projects first. So now I have a vacuum hold down on my CNC. And about the broken amp, the replacement power input board arrived and it blew up as well. Means the PSU is broken, which will run me about 300$ probably. Good thing is that I've watched a movie with one of the spare amps I had in the store and the clip lights didn't even light up once. I didn't change the settings and volume matched everything properly. Means I can now run the quieter amp (fan noise) with much lower idle power draw without any performance penalties. The spare amp does like 2000W total, which is fine with the SKHorn as efficient bass maker and the BOSS platform as efficient TR maker. Now that I think back about the times that I had the bridged clone amp on the SKHorn and this bridged amp on the TR I realize how overkill it was. I watch my movies at -10MV with the EQ at +15db at 20Hz. No dynamic EQ. Will post the first test results some time next week I guess, I will add different frequency tests when I have the time to do those.
  12. Nice bot there. @MemXI love anything that distributes weight across your body evenly, like a good backpack would. I use round slings to move heavy stuff. I built the SKHorn in the basement so I had to move it up a staircase. There is a motorized crane above it, which is good for payloads up to 5000lbs, so I didn't have to worry about it, but moving large MDF sheets has proven to work really well with a round sling over the shoulder, like you'd carry a bag. I moved a 100lbs sheet of MDF like that with ease (with a friend ofc). Straps especially help with unwieldy things like big subs with no handles 🙃 Just secure it well so that it doesn't slip off. You don't want a 150lbs sub to become loose halfway up the stairs. Especially not if you're the person further down the staircase.
  13. Yea if I had no budget concerns I would've put a dozen RF19's in the room already. After thinking about it again, the 21DS115 might not be such a bad choice after all. Its distortion is super gross under free air conditions, which means they're not useful for IB or large sealed cabs. But since I'd have to go with tiny cabs anyways (similar to Ricci's test cube), that could make it work quite nicely. I will think about it the next time I'm dropping an order at B&C. Prices went through the roof now because of the crisis, so I'd wait at least another year anyways. I'll be going through an interesting passage of life soon so I don't even know if I'll be able to keep anything above my 12" sub with me over the next couple years. I think all apps are good for sealed enclosures. I've used winisd in the past, but nowadays I just use hornresp for basically anything since I'm familiar with it. The programs are basically just limited in how many parameters you can list. WinIsd doesn't model horns at all afaik and hornresp is limited to 4 segments, which makes it hard to do complex horn folds or even compound horns.
  14. I was also thinking of adding some sealed cabs to compliment the skhorn below 20hz, but I can‘t find any useful drivers with a lot of displacement and strong motor for an undersized cabinet within a reasonable budget. And to match the skhorn it would probably take like a dozen sealed cabs idk. I can get the 21ds115 really cheap but its distortion below 15hz is appaling for that use. Alibaba seems to be a decent option, but then you notice the 250$ shipping cost per driver...
  15. Please do two 6 driver cubes with those Daytons. I want to see that! DO stands for dual opposed.
  16. If you look at the native frequency response of two extremely popular bass drum mics (mostly used for live events) that question will likely be answered: Audix D6: Shure Beta52A: I like to have two high shelves on my mixing desk for the kick drum, one centered at 1-2khz and one around 4-6khz, which I can individually boost to colour the sound to my liking. Sometimes a broad boost around 1.5-2khz can be very pleasant with extremely muffled kick drums aka Evans emad style. The Shure Beta91 has a dip switch, which basically is a cut around 400Hz (~two octaves effective range). Studio mics generally tend to be more flat, to leave it neutral for the engineer to work with, but most of the midrange will be scooped to make room for other stuff in the mix. That'll be extremely busy if you add an orchestra to a band, or generally have a lot going on (Fallujah - Starlit Path as extreme example). Neuman U47: Keep in mind that mics used for live settings are usually cardioid mics. These don't care much about room resonances. Most 'mud' you'll be fighting will be instruments competing for the same frequency range. Or for example sustained instruments leaving no room for transients in a certain frequency area. If the room is small enough to cause resonance problems in the low mid range, you'll be fighting much much bigger problems anyways (stage bleed). @kipman725Are you sure about the Q of 4? I'd go as far as saying that a change like that will be inaudible to most. Maybe the guy in the PDF mixed up bandwidth with Q there. Agreed, it's most important to learn to interpret what you're hearing. Some people reading such a guide might not even be able to identify a certain problem as "muddy" and try to fix it by breaking something else. I know that from experience, done that long ago when I 'followed' a Yamaha sheet on how to mix. I'd boost all guitars at 2khz no matter what. Today I basically cut all guitars at 2khz because the presence region delivered by amps sounds good with a guitar cab, but not good when you mic said cab and amplify it through the PA. If you cut the presence region you can make the guitars louder without them being ear-piercing, which helps a lot in busy rock/metal mixes.
  17. I love that PDF, it's comedic and informative at the same time! "Do not confuse any other frequency with kick, it is 91Hz" lol! "The first things you need are some familiar test tracks that you have played on a variety of different systems." I'd like to add: the more spectral content the track has at any given time, the better. Aka "Apocalyptic Feasting" by Brain Drill. Venues and Hosts will love you when you blast that song for soundcheck. I also see RTA mentioned quite often, but never that you'd supposed to send the return of a measurement mic into one. I don't like equal loudness contours, as it's based on sine waves and research using bandpassed noise have yielded different results. He also takes a very different approach to handling equal loudness contours. Instead of always trying to achieve a flatter reproduction depending on the listening level (like what the dynamic EQ function on AVRs does, which I absolutely hate), he makes the listening experience at high levels sound like you'd percieve lower SPL levels, which is kinda the approach I'm also taking (and basically the opposite of the AVR approach, which basically makes high SPL listening even mode midrange/lower treble centered).
  18. @SME I had live bands in mind with the 60Hz kick drum range. Studio recordings are very different from live acts. They'll still vary ofc, as not every instrument is the same, but typically the kick lands in the 45-70Hz range. Also keep in mind that the signal processing chain (including the mic) will result in the 100-1000Hz decade being attenuated quite a lot in most modern mixes. It doesn't sit in the mix very well. Yes a natural Jazz recording will likely differ, but anything I've ever experienced live (be it cover music or the actual acts from Robbie Williams, Pink Floyd, Queen, Iron Maiden, Judas Priest and dozens of other Metal bands) followed that principle. I also agree that a wide range rattles the chest, but I disagree that quality of tactile bass is tied so linear frequency response. I get the feeling that TR is tied to voltage sensitivity more than the actual FR. So yes, in perfect free field conditions the TR might track the FR while both are linear, but in a room where you start cutting the modes, the frequency range that gets less cuts will feel more pronounced in TR. I cut more between 10-60Hz than I do above and I get the feeling that the range that I do less cuts in feels more pronounced in TR, even if the FR is linear. Could also very well just be the resonance frequncies of my couch or my own body, who knows! I mainly use Waves' RBass to generate sub-harmonics in the studio. That plugin is pure magic and I love it! When I notice the lack of bass in an instrument during soundcheck of a live show, I often just send it into my suboctaver channel, which does exactly what it sounds like: it doubles the signal once octave lower, which goes through a LPF to not interfer with the original sound too much. I basically always use it when the drummer is playing a Cajon instead of a full sized kick drum. The band I'm "touring" with has a Cajon that kicks at 90Hz. The suboctaver adds a nice fat 45Hz to it and oh boy is it nice! Even the band basically immediately started questioning me about it after the first gig about how I made the kick so massive, it's great.
  19. I've been to concerts with high volume sustained output between 80-120Hz. These were not the most pleasant concerts I've been to. I generally think that the power requirement below 70Hz will be larger than that of the upper bass range. But I think the octaves of 10Hz would also be interesting as it classifies the bass pretty well imo. 10-20Hz content for the cinema crowd, 20-40Hz as sub-bass and 40-80 as the typical high power bass range for live events. Sub 10Hz requirement seems to become less sought after, now that so many people use low-power TR devices instead of a pile of sealed subs. At least that's my impression on AVS atm. I too used to just turn up the sub channel to get more bass before I knew better. It's an easy way and often the only way with simple analog systems to shape the response. Luckily dsp amps are finding their way into entry level PA systems, which gives newbies a lot more flexibility. I like the noise idea. Most high power amps will generate noticable hissing if you're less than 3m away from the CD (on axis ofc), but it won't be super noticable any further.
  20. @SME The test files will ramp up, but not super hard, but also not as soft as some others do. Probably 6db gain per cycle, REW does 6db gain over 3.5cycles, which is fine for 1khz testing, but might already be an issue with 40hz. I wanted to test 60Hz since that‘s around the center kick drum sound, especially for live music. And I don‘t think 80Hz is too useful/realistic as the crossover point of any live PA will very unlikely be any higher, so 80Hz would already be shared by two amps 50:50 at an example of an 80Hz bw crossover. I think I‘ll do octaves from 60 to 7.5 then. But I don‘t know if I can get useful results that low, we shall see.
  21. I was guessing that if an amp does 20 cycles at 1Khz at a certain power, it would do 1 cycle of 50Hz at the same power. Are amps that bad at keeping up current for longer intervals? I think I'm gonna go with 10s test duration. Even the intense EDM song I looked at had a crest factor of 6-7db. And the dubstep sine waves are usually not full power because some headroom is needed for kicks. And I certainly don't wanna blow up any amps anymore. Especially when I'm testing amps north of 5 grand like that LA8 (although I doubt that that amp would NOT have very good protection circuits). I don't like the CEA-2010 test since it hides the temporal aspect and ties it to the frequency. I will most likely create some custom test files, basically sine waves which ramp up quickly. I can do a visual overlay so you'll see where exactly the amps drops off in output voltage. Also, CEA-2010 does not contain a single full output cycle. Just one peak will be at Vmax and the neighbouring peaks will already be a little quieter. Most amps I've seen have HF protections which mute high output above typically 10k anyways. I don't see why high output at 16k would be useful, as the strongest CDs do like 200W, so even if you have like 2 to 4 of those like in very high power line array elements, you don't need 10KW or anything for that. A scenario like that usually has one amp channel for one speaker. I was thinking about doing octaves in the bass region: 60Hz, 30Hz, 15Hz. Any higher than 60Hz would end up in the typical crossover region, so not super hard on amps typically and any lower than that will probably not be possible for me to get super accurate results for. One can gauge single digit results from the 15Hz performance anyways.
  22. Yea the blue PCB sure looks more modern 😄 I don't know how the FP-13000 (14k)'s internals compare to the 10kQ (which is I guess the amp in this picture since there are 4 amp modules), but to me it seems like at least the Sanway clone (and a few others I've seen) took the 'more is better' approach and squeezed more caps and seemingly slightly larger heatsinks in. What wierded me out was the amp starting to smoke when I had it on for half an hour with the fans disconnected. Seems like the 150W or idle power draw is dissipated around the rectifier area, but I couldn't find where the smoke came from since the case was closed at that time. No visual clue remained.
  23. I have since updated my device OS and that seems to have fixed the issue. All good 🙂
  24. Bending the leads through the holes wouldn‘t be practical for machined assembly, I doubt anybody would do that. Q50 is probably installed on the Fp14000. The FP13000 is exactly the same amp with a few components missing. Probably the transistor there and two caps for the PSU.
  25. One funny thing I‘ve noticed thou was one of the transistors not being soldered to the board. I‘ve corrected that now
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