Jump to content
The Klipsch Audio Community


  • Content Count

  • Joined

  • Last visited

Community Reputation

67 Excellent

About karlson3

  • Rank
    Forum Veteran

Recent Profile Visitors

1875 profile views
  1. PRV's D270PH-S - rated for a 500Hz crossover. $35. (Horn on data sheet not identified) This might be nice for the diy-er on a budget who wants to make La Scala or Cornwall type. https://prvaudio.com/wp-content/uploads/2019/08/PRV-Audio-D270Ph-S-Datasheet.pdf
  2. A question, lets say I wish to emulate (in the simplest "passive" fashion) a SE tube amp's major response and Z-out characteristics with a cheap TPA3116D2 amp - what might the network look like? Could it be as simple as an air core inductor with some resistance? I don't have a ciruit modeler to look at Z-out vs F plus the learning curve now might be tough. There used to be a program called ACNAP which could use simplified transconductance models rather than curves to roughly approximate a tube amp with output transformer Z-out. It would be interesting to hear how close - or far away the hacked cheap amp would perform vs the tube unit. I have a cheaper version of the Breeze - -$25 shipped from Amazon with 14.5V 4.5A power supply - only used so far with headphones where it does a very good job. Its binding posts look very delicate. I've not opened it. The somewhat lower voltage supply might help it live if caps aren't great.
  3. Jeff, might this be done successfully (noting limitations) on a smaller scale with a 6BQ5? FWIW I'd guess a tube driving a MOSFET (like the Bravo/Indeed headphone amps but with real voltage swing vs starved anode area swing) might (???) be better on the cheap than a poorly executed PP tube amp. I dumped my EAR 509s in the 80's as felt they made Ivan Kozlovsky sound "old" ( he was 70 at the time of that recording - lol) GREAT build - neat report.
  4. cool - - ( but I mainly watch movies from early talkie - 1940's and don't like CGI - only suitmation Godzilla 4 me) don't know if the hornresp model I grabbed from AVS is the production model but here how it goes with one 21" driver - -efficiency where it peaks around 80Hz ~"60%" I tried downscaling it x 0.71 for my Stereo Integrity 15 but the peaking area looked too sharp. It should be nice. Input at tuning for 28.3v midband input is around `1200 watts Here's a comparison between the Devastator and a THTLP which is just about half its size (2 pi and no eq/highpass on either)
  5. The L-pad should sound good enough and add some flexibility if the speaker is moved - - just mark its level position(s). The tweeter could be placed "back" in the plane of the midrange driver. If so then use felt or perhaps carpet on top of your 811 horn to reduce reflections. Here's an L-pad calculator https://www.diyaudioandvideo.com/Calculator/DriverAttenuationLPadCircuit/ say you wish to attenuate your 811 by 3dB - then enter the nominal impedance of your driver and the amount of attenuation (and a wattage - if interested) Then the calulator will show the series and parallel ("shunt") resistors plus the power the driver receives. For instance when 16 ohms and 3 dB attenuation are entered, the calculator shows the values below. One would use typically whatever 5% value is closest. With the adjustable pad you can dial the amount of attenation in by experiment then if wanting to make a fixed L-pad, measure the pad's series and parallel resistance with a multimeter and find which fixed resistors to purchase.
  6. how about putting a 16 ohm L-pad "before" your driver/horn combo? You could take an adjustable L-pad and find a setting which sounds / measures right to you then replace the series and shunt Rs with fixed resistors of decent quality. (811 and 511 make good midhorns)
  7. I'm going to take just a guess - that a number of "high end" tube amplifier products were/are the result of listening rather than following exact rules of the longest AC loadlines and best-positioned operating points per Radiotron manual vs tube characteristics and that perhaps ARC, and Quicksilver have done this practice and certainly Bruce Moore and Scott Frankland. (It would be good to have a scope to hunt down potential oscillation problems - my 8417/417A tube sure oscillated enough to block the signal) I once had a modified Dyna Stereo 70 which had probably been modified per Eisenson's "TU-BE OR NOT TU-BE" and for some reason it would LF "motorboat" on a box speaker - but would play on the resistive Magneplanars. Some designers seem not to be so fixated on things. Grommes designer Al Hart in a note to me seemed glad to see tubes dead and happy with an op amp RIAA stage with global feedback. Stu Hegeman in later years had a similar preamp. (I'm sure the HAPI is about forgotten vs his Citation I & IV tube units) I like to see those who are passionate and experiment (Jeff included) The Japanese "Ultra-Fi" movement several decades ago imo was a very good thing for those who love horn loudspeakers. Jeff could easily throw high H chokes on the chassis, series pass regulators, big caps - - but apparently has found something which works better for his* sense of how music should sound. (* people don't hear/perceive things the same) FWIW I've heard "a little" hum from commercial tube (and solid state) amps in my lifetime. Audio - like other hobbys, politics, religion, can bring out strong opinions. Maybe its best to use that phrase - "lets agree to disagree" .
  8. certainly impressive and the gorgeous case must aid in reducing sensitivity to microphonics. I've heard (and owned) a few preamps through the years including Bruce Moore stuff, Tube God's NB1, P-F, Theta, etc. and some homemade stuff. Although loop feedback isn't popular, it might be fun to do a Stu Hegeman tribute with cascade feedback pair driving passive RIAA per Citation I and IV, but throw out the 1000 contacts and superfluous stage stuff. I like the idea and sound (and idea) of an anode - follower with low gain vs cathode follower. My fingers/hands are numb these days and doubt if could solder for more than a few minutes. I've got a mu-follower RIAA preamp (lumped passive RIAA) w. stepped attenuator laying on the floor gathering dust. It needs some caps soldered and coin cell batteries for one stage's bias.
  9. I've had only 2 hr sleep so mighta botched something - here's power response of a Kappa12C in LS vs K33E and vs a JBL M151 guitar 15. I'd have to have a single segment expansion to get the directivity Do PWK's bifucated folds tend to be able to go higher for a given bulk horn than single path?
  10. for horns - Danley and his MEH provided one of the best leaps in SQ. For the capable DIYer and amplifier above flea power, that's one way to go. (is there a good and available substitute for the little MISCO sealed back mids ?)
  11. re: liquid rubber dip - that does sound like a better idea as rope putty eventually dries out - if there is a significant peak then that's good to LC(R) trap as seen the magnitude pretty high and peak that forms an interference source with the tweeter ( unless you like the sound - lol)
  12. I've never had LS (do have Khorns + H1) - seems to me the original with capacitors which flavor it best to one's taste (perhaps on the budget, KBG, MBGO or decent motor run poly battery biased) when fed with a good source (for me - no op amp in the DAC or preamp) would be about as good as it gets. FWIW I would want no particle board, and prefer stiffness from bracing rather than thick walls. K400 (and 700) seem to do better with rope putty than 511B. Also - if there happens to be a peak in the upper range of the midhorn/driver combo and there's no midrange lowpass L , it would not hurt to apply the old "p-filter" trap using RTA or repeated sweeps to properly center the LCR filter. K55v was a pretty good driver overall. Its discouraging to see new chunky compression drivers in the $100-$150 range but none to do the work and lower range needed in the classic Klipsch midrange horn setup. What the world needs is a great $100 phenolic 1 inch (and larger) format horn driver. (I remember when High Fidelity published their A447 review ) Here's that review:
  13. here's ~ a Mini - Punch sim with Delta Pro12 450 (and compared to LS/K33E) It probably would be better to seek a driver with higher Re if using with low/zero global feedback tube amps. Bet it can sound real good on vocals if everything else is matched up well. The second sim is the Mini Punch with back chamber sealed and set the same volume (~58 liters) as the stock La Scala. Sealed MP
  14. the DJK (RIP) vented La Scala mod if adding about 2 cubic foot to the back chamber and tuning to ~33Hz should look pretty much like the sim below. A final qts of ~0.31 for the woofer after inductor DCR and amplifier source impedance are factored would fit the 6th order reflex treatment closer.
  15. (I've got a Dixielander with mouse eaten 8 - it won't take a 10 plus the back chamber is vented) it takes good skill to do a Classic's throat (my hands are numb and couldn't do it when young) FWIW - a comparison between 0.83 scale Classic with Delta 12 Pro 450A and La Scala with K33E spec
  • Create New...