ScaleAutoArt
Super Member
I haven't checked the voltage yet because the tube are glowing normally. Should I check it anyway and are there symptoms aside from what you observed on yours before you did the corrections?
Little Bear Tube Phono Pre??
- Thread starter sled108
- Start date
sled108
Super Member
Let it Play like that for now...As long as they Glow Dimly, and the Same...You are Better off than Hitting that 6V4 with 7.3v on the Heaters. The 6.3v is only for the Rectifier...The 15v AC is Rectified to at least 19v DC...Then it's Fed in Series thru the 6N2P's Heaters..
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Interesting...... Got it! Many thanks! I'll post again after mine arrives and I go thru the basic checks. Tom D.
ScaleAutoArt
Super Member
I just complete installing upgraded caps per Sled's suggestions and I am very pleased with the results. Better soundstage and no muddyness. The hum also reduced by at least 50%...not sure why. I also put
damping sheet on the and under the trans.
I recommended making these mods. It is another level.
Now for some tube rolling...after theses caps have some more break in.
Cheers
damping sheet on the and under the trans.
I recommended making these mods. It is another level.
Now for some tube rolling...after theses caps have some more break in.
Cheers
ScaleAutoArt
Super Member
The smaller two were replaced with the Russian paper in oil caps and the other four with the WIMA MPK10 as recommended. Total cost about $14.00! [plus my free soldering skills].
I have 4 matched WIMAs if anyone wants them
I've got one of these things somewhere between here and China! If your caps are available, I'd throw my name in the hat! Hopefully mine will arrive within the next week or so. Seems my pre-amps took about 3 weeks..... so it's now been 2 since ordering this phono pre. Maybe by Friday??? Thanks, Tom D.
ScaleAutoArt
Super Member
PM me and I will arrange to put them in the mail to you. Get a pair of these as well:
http://www.ebay.com/itm/221175218161?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Peter
ScaleAutoArt
Super Member
So...the LB sits on top of the foil and you connect the ground to the foil. Nothing to the LB ground terminal?
BTW...I did reduce the noise with the cap change and damping material. Not sure which did it but it helped. Put rectangles of the sheet on the sides of the trans and on the plexi below.
ScaleAutoArt
Super Member
OK ...sorry if I am a bit slow...so the foil to the LB ground and the TT to the LB ground as well...correct?
Pics when available?
sled108
Super Member
Correct...They both go into the LB's Plunger Ground...
ScaleAutoArt
Super Member
OK...I tried foil first...worked, then just found an old candy tin that's the same size and flipped it over, grounded it. Less hum for sure. A cheap dual purpose isolation base..paint black and fill with sand
Perhaps I am going overboard here!
Perhaps I am going overboard here!
Hello all, please be gentle I hope my question isn't too stupid.
Due to space constraints I use an Aktimate Mini system. http://www.whathifi.com/Review/Epoz-AktiMate-Mini/ I am planning to buy a Pro Ject Debut turntable to link to it and need to buy a phono pre-amp. My initial thoughts are to just go with the Pro Ject phono box but I had a scan of ebay and found the Little Bear (and hence this thread).
I guess my questions are:
a) bearing in mind the system I am linking it to will it offer any benefits?
b) I see you guys are modding yours, how does it run "out of the box". At least initially I wouldn't be carrying out any modifications.
Be interested to hear your opinions. Thanks.
Due to space constraints I use an Aktimate Mini system. http://www.whathifi.com/Review/Epoz-AktiMate-Mini/ I am planning to buy a Pro Ject Debut turntable to link to it and need to buy a phono pre-amp. My initial thoughts are to just go with the Pro Ject phono box but I had a scan of ebay and found the Little Bear (and hence this thread).
I guess my questions are:
a) bearing in mind the system I am linking it to will it offer any benefits?
b) I see you guys are modding yours, how does it run "out of the box". At least initially I wouldn't be carrying out any modifications.
Be interested to hear your opinions. Thanks.
sled108
Super Member
For a Mini System, I would say that you'd be better off with an Art DJ Pre...
ScaleAutoArt
Super Member
Or the Pro-Ject he was thinking of.
sled108
Super Member
Well Now...The Tin Foil might have been Stupid Simple, but I've found a Better Hum Buster...All that you need is the Thinnest Bare Copper Wire...You take around 5' of it and Snug one End under the Back Right Top Plate Nut, then run it around the Front Right Nut and back to the Back Middle Top Nut. Then run it down to the Bottom Allen Bolt, over to the Inside X-Former Bolt then around the Left Bottom Allen Bolt and across to around the Bottom Right side one. From there you just run to Ground with the TT Ground. This is for those of you (Like Me) who don't have a Sweet Cookie Tin handy...There might be Better Patterns...It can be something to Tinker with...
