rabski

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About rabski

  • Rank
    Moderate to fair
  • Birthday Private

Personal Info

  • Location
    Kettering
  • Real Name
    G. Rumpty Git

Wigwam Info

  • Turn Table
    Well (bad) Tempered
  • Tone Arm & Cartridge
    Dynavector XX-2
  • SUT / Phono Stage
    Kairsound SUT
  • Digital Source 1
    Pioneer/Marantz
  • Digital Source 2
    Netbook
  • DAC
    Audiosector/FiiO
  • Integrated Amp
    Leak + others
  • Pre-Amp
    Soon come
  • Power Amp/s
    845 SET / KT88 PP
  • My Speakers
    Living Voice IBX R2
  • Headphones
    AKG
  • Trade Status
    I am not in the Hi-Fi trade

Recent Profile Visitors

3,190 profile views
  1. rabski

    Kegworth 2019 - Suitcase Challenge

    Except for when we're helpless...
  2. rabski

    Can you tell what it is yet?

    Sooner than you know what This one's relatively simple. I did one almost identical last year and it worked nicely, but I gave it to a mate because I already had the Welford at the time. It doesn't drive the tubes too hard. The Va looks high, but so is the cathode voltage in the follower section so the drop across plates isn't that great. With almost all small signal stuff, the 'trick' (as I've been told and subsequently found out the hard way) is to try not to have to elevate the heater above ground to avoid a big voltage gap between cathode and heater. There are various designs around based on an early version of much lauded Japanese pre using a 5687. Elevating the heater has some benefits, but also some downsides. More bits needed for a start. There's enough room in the case to mount a transformer on top and add an EZ81 and caps. I like the idea of a separate supply though. It makes hum reduction much easier. Having more space is always easier and I also want to mess around with some of the daft tubes I've got lying about, so having the flexibility to get a much higher B+ is an advantage. I like big tubes anyway...
  3. rabski

    Can you tell what it is yet?

    Sounding not alf poor
  4. rabski

    Can you tell what it is yet?

    Peter Daniels Audiosector NOS DAC board. It's a classic non-filtering, non oversampling using a TDA1543. The other board is a hacked around Chinese tube buffer, now running a pair of small pentodes. The odd board is a voltage regulator. The tubes are powered a little lower than the ideal anode volts, but it's working far better than I expected for a quick throw together. I need something 'tween the CDP and the 845 because the workshop is covered in the bits of what will soon be a tube pre with a 6922 cathode follower design and a separate tube rectified supply. Unless I change my mind halfway through. With that in mind, I've massively overspecced the power supply. A 330-0-300 transformer and a GZ34 for a 250V B+ is, I know, a bit overkill, but I had the bits lying around, so why not?
  5. rabski

    Calling all Kondo/Living voice officianados

    I hope not, but who knows?
  6. rabski

    Calling all Kondo/Living voice officianados

    There are no special artisan techniques required to cut a cable. I'm not particularly attracted to Samurai swords, but I most certainly would cut a Kondo cable in my workshop. In fact, I have done so a number of times. I am probably not the only one to cut Kondo cable for that matter. I know Kevin uses it in the Olympians. Though I may be wrong, I doubt he sources the precise lengths from Japan for this.
  7. rabski

    Calling all Kondo/Living voice officianados

    A brief look at my profile will show you that I use Living Voice. I have had an M7 here, and some other things that have come to me via Kevin. Nothing has changed, except audio waxes and wanes for all of us in comparison with other necessary expenditure. At the moment, I prefer to get my hands dirty rather than expose my credit cards to further abuse. Needs must.
  8. rabski

    Can you tell what it is yet?

    Nearly. It's currently warming up with 2000 Motels and doing a very decent job of it (hint: Audiosector).
  9. rabski

    Calling all Kondo/Living voice officianados

    I know he does. I know Kevin and Lynn fairly well.
  10. rabski

    Can you tell what it is yet?

    Been clearing out the workshop and found some small cases I'd completely forgotten about. Perfect opportunity to throw some bits together that have been sitting in horrible cases for ages.
  11. rabski

    Audio Note V10 The Preamp kit

    You lucky so and so! Brilliant find that. What a lovely build.
  12. rabski

    Calling all Kondo/Living voice officianados

    Of course you can cut it and treat the ends as described above. How do you think Kondo was able to offer different lengths? "...thermically and mechanically disrupting/shocking the orientation and architecture of of the metallic nuclei in the sea of electrons..." God, I hope you're being humorous.
  13. rabski

    Amp or Valves?

    Running normally, the only illumination from valves is from the heater filament. Apart from directly-heated triode designs, this is almost always a common supply to all the tubes. A bang/pop and sudden change in brightness might suggest a partial short in a heater. If all the tubes are of a similar age and long used, it's just imaginable that this could cause a quick spike in the heater supply that could take out another tube filament. Unlikely, but certainly not impossible. When you say 'brighter' this could be heater filaments, but it could also be from the anode. If you see a blue glow, or the outer metal parts inside the tube are glowing red. Pull the power straight away. A tube will, incidentally, never small burned. Any unusual smell will come from other components when damage has been caused by a tube internally shorting or going into 'runaway'. With regard to autobias, there is true auto autobias and cathode bias. From what I can see, the Prologue is quite rare in that it has 'real' autobias with an adaptive circuit. This should mean that unless there is a fault with the circuit itself, there should never be an issue with different tubes. However, the autobias setting will depend on the type of tubes originally supplied with the amp. It cannot 'know' what power tubes you are using, and will simply auto adjust to the correct bias based on what it was originally set to. As the manual (online) suggests EL34s can be used, it still suggests that they are going to be run a little 'hard'. If a circuit can use EL34, KT88 or KT120, I'd personally prefer to stick with KT88 or KT120. Not the least because from experience with some Jadis in the past, and the odd pair of PP KT88s I have, they sound better anyway. Simple answer as far as I can see is that if it runs properly and sounds fine with the KT120s, then it looks as though the fault is with the EL34s. That's obviously not a guarantee, but a sensible guess. Of course, keep a close eye on it. If there's any sign of one or more of the 120s getting brighter, then have the amp looked at. If it stays 'as is', then either get someone to test the EL34s or bin them.
  14. rabski

    Impedance 4 / 6 /8 ohm question ?

    It also very much depends on the amplifier design. There are no absolute answers, and speakers are always a 'nominal' impedance. The actual load they present to an amplifier will vary depending on frequency primarily. And vary massively. I can think of at least one speaker that presents loads varying from under 2 ohms to nearly 40 ohms depending on frequency. As a rule of thumb, it's best to match quoted nominal impedance with the amplfiers quoted 'ideal' load. If an amplifier is quoted as delivering x watts at x ohms, then the x ohms will generally be it's best match. However, there are few amplifiers quoted at 8 ohms that are going to fall over and die into 4 ohms. If you can find them, look at the more detailed amplifier specifications. They may well quote for example a range of distortion figures (x% at 8 ohms, x% at 4 ohms suggests the amp will have no problems running intyo 4 ohms). For solid state amplifiers, if they are specified at 8 ohms, then running 4 ohm speakers means they will need to provide more current (ohms' law). For most, this is not an issue. If your amplifier has plenty of headroom (more than enough power), then you're unlikely to stress it. I'd only worry if it's marginal in terms of power delivery. The situation is a bit different with valve amplifiers, as there is a 'match' between the speaker and the output transformer. There is almost zero danger of amp damage, but the frequency response can be altered.
  15. rabski

    Jokes, old or new

    And he did! Forgotten actually what a good rock voice he had.