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Post by seroxatmad on Sept 16, 2008 19:50:35 GMT
Hi
I am thinking of buying a little dot III off ebay. Anyone got comments on it! It will be interesting to compare to my Millet Max and Kumiza amps.
John
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Post by sometrolls2 on Sept 17, 2008 4:22:50 GMT
Have you given the Kumisa a JLH and discrete opamp yet?
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Post by seroxatmad on Sept 17, 2008 4:27:05 GMT
Hi
The kumiza only has a OP amp for the DC servo.
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Post by sometrolls2 on Sept 17, 2008 13:39:03 GMT
The people that make the Burson opamps are about to release a new revision to their model above the Burson one, and release an even better model. Being the OEM they charge a lot less than Burson and do a handy extension lead. www.audio-gd.com/enweb/pro/diy/OPA.htmAdding one of these to the Kumisa or Jaycar is the cheapest route to a discrete amp. Ebay has had cheap stepped attenuators. I'd max out a DIY solid state before buying a new tube amp.
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Post by prawn on Oct 8, 2008 12:36:12 GMT
Sorry I can't comment on the Little Dot but I do have a Kumisa amp in my arsenal which has benefitted from following - in order of perceived improvement; 1. Replace output devices (BD139 with MJE243 and BD140 with MJE 253) This has stiffened up the bottom registers subtly but noticeably and eradicated some of the clinical sting I asssociate with the old BD series. This mod works well with the old WNA amps if any are still in use. 2. Fit a stepped attenuator - normally I don't like these with opamp based amps with their high input impedances since RF is more readily dumped into the rest of the amp (there's a hell of a lot of wiring in some of these attenuators which act like an RF aerial). The lowered input impedance of the discrete devices in the Kumisa doesn't seem to attract this effect. 3. Fit some decent heat sinks to the output devices and increase the bias by about 50%. The additional sweetness in sound is noticeable. 4. Add a simple Zener network at the output jack - there have been reports of HF oscillation in some setups. I haven't got a 'scope but there seems to be a slight audible improvement in the treble region. 5. Lose the bipolar caps C19 through to C24. Ti's site explains how - this is a worthwhile tweak if you haven't done it. 6. Put the tranny in another enclosure if possible. No less than PRR on another forum suggests that the opamp servos in these sort of amps may have a bearing on the sound but I haven't got the inclination to fiddle about in this respect. I bloody hate opamp rolling! Best of wishes mate!
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