And what did we buy today?

I hooked the Minimus 7's up last night and also found the tweeters too harsh for listening to music. I tried three different Lepai chip amps and two different 12 volt wall wart supplies, all with similar results. The 7's might be just the ticket for finding aliasing in my digital synthesizer experiments, but I am going to try the Cerwin Vegas before going much further down this road. Everything sounds great with a pair of budget Sennheisers plugged directly into the Focusrite Scarlett.
 
i always suspect, that tweeters, are not so much to blame,

as the crossover capacitor, that is causing the real problem.

electrolytic capacitors, generate distortion.

plastic are generally much preferred, for low distortion.

night and day difference


got 20, polypropylene 4.7uf caps for $16us specifically for the Minimus 7s
 

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i always suspect, that tweeters, are not so much to blame, as the crossover capacitor, that is causing the real problem.

electrolytic capacitors, generate distortion. plastic are generally much preferred, for low distortion.
I swapped the Cerwin Vegas into the setup and they do sound much better. They are however three times the size of the 7's. This is probably the first time they have been used in 30 to 40 years and I have never been inside them. Any electrolytic inside these are probably dried out, so I may crack them open for a cap swap.
 

kodabmx

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2011-10-31 1:00 am
Toronto
I got an alignment protractor/stroboscope mat for my TT.

I had aligned it with a universal arc protractor for Technics 1200's (which I thought were the same overhang/offset as my Toshiba - ooops) and it was not bad, but after aligning to the protractor Stevenson, there is far less sibilance.

For those who want a great sounding TT setup without bankruptcy, get a Stanton 680 cart (or Pickering XV-15) and use an LP gear vivid line stylus. For ~200$ you get the sound quality of a 2M black.
 
Nice! That interior looks great. So how does the Burmester sound?
Sounds better than any BOSE, HK, B&W, etc. I've heard recently... especially when I retune the exhaust from sport+ to comfort :-; ;).. the strong suit seems to be great spatial focus, plus the ability to shift things around extensively. Bass is surprisingly deep and clean, given there is no true subwoofer.
 

kodabmx

Member
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2011-10-31 1:00 am
Toronto
Arrow decided to basically give away the VPT12-13300 (~12$USD) that I use pairs of for OPTs so I bought eight of them! Anyone need an amp for a good price? My savings is your savings.

I also bought a couple of styli for the phono cart, a set of 6550 for an amp I will try to sell, and a few other things...
 
Nice. FYI I've been running 12GE5 in triode 320V B+ 60mA per tube 24/7 for weeks now. No issues. Basically any sweep tube connected as triode in this set up won't run away in my experience. I use an autobiasing board though (AB-4).
The 6GE5 is a 6DQ6B in a Compactron bottle without a plate cap. The 6GF5 is the same tube with its plate wings clipped enough that it can be stuffed in a skinny Compactron bottle. Being old school sweep tubes, you can probably get away with running then in triode at 320 volts. I have a small board that runs the skinny 6GF5's in UNSET/CED mode for 80 WPC on 500 volts. There is no plate glow after 10 minutes of full power sine waves. Many years ago I tested some E130L's into some dumpster toroid OPT's. The smaller toroids gave out before the tubes did, so I plan to try the E130L's and some NIB 17DQ6's that I have with these transformers. Of course, I have lots of bigger tubes to fry too.
 

kodabmx

Member
Paid Member
2011-10-31 1:00 am
Toronto
I've had two tubes melt down. A 36LW6 and a 6P45S. The 36LW6 still works I think, the 6P45S cracked. Both times the problem wasn't runaway but a faulty grid connection. In any case, I have built a PPP 6P45S amp running into 1k3 load that will do 113W at 30Hz :) 320V, 120mA... They are nice in the winter when I want to heat the room :D
 
A little of this and a little of that, like three 1590BB boxes, some foot switches to go with them. Just a bit earlier a bunch of 100K pots, some more knobs, a PT2399 echo board to go with a lo-fi noise thing more my grandson. (The rest is MFOS' WSG that I got from a fella. He had made a noise-thing with a Grits-something pedal unit.)
Then I am waiting for a bunch of 10K potentiometers, phenolic resin boards so I can restore/rebuild my Priboi amp, and ordered various components in order to start building the Transcendent T2000 synthesizer, as I got the PCBs just after Xmas.