Jump to content

grendel23

Regulars
  • Posts

    79
  • Joined

  • Last visited

Posts posted by grendel23

  1. 1 hour ago, Mikekid said:

    Who the heck remembers exactly what their system sounded like weeks/months ago?

    When I bought RF7-IIIs and a RC64-III I at first thought they were somewhat harsh. I played pink noise through the mains while I was at work for several days and tried them again and they were smoother. To check if the speakers were changing or my ears were becoming used to the sound, I compared the mains with the center channel. After perhaps 100 hours the RF7-IIIs were noticeably more mellow than the RC64-III. I then ran the center on pink noise for several days and then the center and the mains sounded the same. I suspect the woofers were becoming more efficient once the suspension loosened up.

    If I didn't have a reference to compare, I would have doubted whether the change was real, but after hearing a comparison in real time, I was convinced.

    • Like 2
  2. 13 hours ago, Islander said:

     

    It seems to me that the more capable tweeter would be the better choice, since it would be more likely to be operating in its most linear range.  Since it would be operating with less strain, it would be more likely to be able to provide accurate reproduction of the signal it gets.

    Before I bought AXI2050s I was running 3 way using DE10s with LMAHLs for high frequencies. These sounded very good.

    Once I put the Celestion drivers on my K-402s, I went to two way. The AXI2050s sounded better to me.

    • Like 5
  3. 4 hours ago, henry4841 said:

    My sweet spot for SS is 25 watts.

    I am running a 25wpc Pass design class A amp on K-402s with Axi2050 drivers. For horn loaded speakers I find that to be enough.

    The original ask was for direct radiator bass. On those speakers I have found I prefer amps with deep current reserves. Especially where the impedance dips well below 4 ohms.

    • Like 2
  4. I owned RF-7IIIs. I had them on an amp that would deliver 600wpc at 8 ohms.

    They didn't audibly distort even when the clip lights were blinking. My ears couldn't take more than a few seconds of that and the speakers wouldn't survive long either, but it was very impressive.

    If you listen to music without much bass at normal volume, these would be happy with 50wpc, but why get these speakers unless you can feed them properly? I would invest in a good 200wpc amp.

    • Like 1
  5. When I had RF7IIIs, I was running a QSC PLX 1804, 600 WPC into 8 ohms. I could play Daft Punk and use all of the available power, (clip lights blinking).

    The speakers just kept getting louder, no breakup or noticeable distortion.

    I don't know if they would have held up long at this level, but it was impressive to start "Human After All" for guests at bowel loosening volume.

    I agree that 100 WPC is more than enough for normal listening, but once in a while...

  6. In the plant where I work (controls engineer) we braze propane cylinders together. We apply a braze paste of copper powder in a liquid carrier to the seam.

    They are then put through a furnace with a reducing atmosphere at 2000F. Part of our quality control after brazing is to pressurize samples until failure. The steel fails before the brazed joint.

  7. On 8/25/2022 at 9:57 PM, Blackcat said:

    Class-A  for the sweet top end though not SET with Class-AB for the base for a tight bottom end?

    I have K-402s with AXI2050 drivers. I have tried Class D, Class AB, Class H, chip amps, tube monoblocks with push pull KT120s, 300B SET, and Pass design Class A.

    I am running the class A amp on the AXI2050s. To me it has the best dynamics and the most natural sound. I am running Class H (AB with a fancy power supply) on the bass.

    • Like 4
  8. 22 hours ago, Dr Morbius said:

    So grendel, how do you adjust the line voltage from your outlet to your amp? 120 volts is fine for me, not 128 or whatever.

     

    I wired a 12v transformer in a buck configuration. If you use a variac, it has to be rated for the entire load. A bucking transformer only needs to be rated for the percentage of the voltage reduced (or boosted). So a 1KVA 120VAC load with a 12VAC buck or boost only needs a 100VA transformer.

    This is much cheaper than a decent variac.

    I used a center tapped transformer with a DPDT switch so I could switch between 6 and 12 volt reduction.

    If you do this, add a fuse, size the transformer conservatively and make sure there is enough cooling.

    • Like 1
×
×
  • Create New...