Search found 56 matches

by grog
Wed Jun 24, 2015 9:09 am
Forum: Everyones Projects
Topic: build log, chinese audionote kit 1, 300b se
Replies: 34
Views: 22606

Re: build log, chinese audionote kit 1, 300b se

to resurrect this thread .... I've been listening to the amp for some time now, and have a really annoying issue i can't trace,,, i have a rustling/crackling noise mostly from the RH channel, I've swapped valves around, and even replaced the EH 6SN7's with US built ones, but to no avail.. looking ca...
by grog
Mon Apr 06, 2015 4:47 pm
Forum: Buying and Selling
Topic: Wanted: 6sn7 just one, for audionote kit 1
Replies: 0
Views: 2214

Wanted: 6sn7 just one, for audionote kit 1

i'm after a 6sn7 to upgrade EH russian valve in there presently.
not after anything mega expensive.
maybe you've got a single valve spare somewhere ?
might also consider a pair of 5687 as well
thanks
george
by grog
Wed Dec 11, 2013 2:10 pm
Forum: Valves
Topic: 5u4gb rattling / rustling from valve itself.
Replies: 3
Views: 4242

after some googling it seems that its not so uncommon for 5u4gb's to rattle. i also noticed that the tx secondary is 100 ohms, this might be a bit low? i found the min resistance for 5u4 (non gb) is 170r. current rectifier is EH, options are, add series resistors, 39r to each anode, or new rectifier...
by grog
Tue Dec 10, 2013 2:52 pm
Forum: Valves
Topic: 5u4gb rattling / rustling from valve itself.
Replies: 3
Views: 4242

5u4gb rattling / rustling from valve itself.

i powered up the kit1 tonight, all seems ok, voltages all near enough. only problem is a rattling/rustling/tinkling from the rectifier itself. it's the same sound as light bulbs sometimes make when they are on their way out. should i be concerned? it's audible from near the amp but i'd describe it a...
by grog
Thu Dec 05, 2013 9:13 am
Forum: Everyones Projects
Topic: build log, chinese audionote kit 1, 300b se
Replies: 34
Views: 22606

ok, thanks, this is for the input tubes, (6.3v) but still only 0.4w, i'll throw them in, i was just hoping to avoid a few more components, schematic here for easy ref. http://www.4tubes.com/SCHEMATICS/BY-BRAND/Audio-Note/Kit1/kit1-psu.gif http://www.audiofil.net/data/upload/20090315_102640_kit1-audi...
by grog
Thu Dec 05, 2013 3:02 am
Forum: Everyones Projects
Topic: build log, chinese audionote kit 1, 300b se
Replies: 34
Views: 22606

yes- -i should use the 100r resistors as a virtual center point?
or
yes- - just connect one side of the heaters to the elevated voltage (or gnd on the other tube)
by grog
Wed Dec 04, 2013 4:43 am
Forum: Headphones
Topic: Suggestions for a headphone amp
Replies: 0
Views: 8248

Suggestions for a headphone amp

now the 300b amp is nearing completion, i'm thinking of the next project as always! i currently have a hybrid 'starving Student' amp using Ecc82 and FET class A buffer. the next one needs to: A) sound better than the SSHA, B) be all valve.. of course, C) driver most headphones including low impedanc...
by grog
Wed Dec 04, 2013 4:13 am
Forum: Speakers
Topic: Tall Narrow Multi-driver Speaker Design
Replies: 22
Views: 13463

for interest there are a couple of nice new drivers for line sources, one is 40mm chassis size, the other 59mm, http://www.tymphany.com/files/TC5FB00-08%20Preliminary%20spec%20sheet%20Rve1_0%20%20%2020121126.pdf http://www.tymphany.com/files/TA6FC00-04%20Spec%20Sheet%20Rev%203_0%202013-1-14.pdf i'd ...
by grog
Wed Dec 04, 2013 4:04 am
Forum: Everyones Projects
Topic: build log, chinese audionote kit 1, 300b se
Replies: 34
Views: 22606

pushing on with the build, hopefully complete next week, a few more questions, there is a strange arrangement in the PSU, the outputs for 395 and 375v are from the main B+ via dropping resistors and caps, but the final smoothing cap does not have it's -ve terminal returned to the star earth on the P...
by grog
Tue Nov 26, 2013 2:07 pm
Forum: Everyones Projects
Topic: Ideas For EL34 Pentode Push-Pull Amplifier
Replies: 105
Views: 44704

I've probably missed this somewhere, but which pre amp are you running to get the balanced outs?
by grog
Sat Nov 16, 2013 12:25 pm
Forum: Everyones Projects
Topic: build log, chinese audionote kit 1, 300b se
Replies: 34
Views: 22606

exactly...
just wondering if i should used screened cable to go from driver pcb to 300b grids,
by grog
Sat Nov 16, 2013 9:27 am
Forum: Everyones Projects
Topic: build log, chinese audionote kit 1, 300b se
Replies: 34
Views: 22606

time for an update, work on the amp has been sporadic, too much going on at work at the moment, anyway see some progress pictures below. upgraded copper binding posts, http://gallery.seloc.org/albums/userpics/27715/terminals.jpg assembled boards in place http://gallery.seloc.org/albums/userpics/2771...
by grog
Thu Oct 10, 2013 8:15 am
Forum: Everyones Projects
Topic: Buffer Amp - unity Gain
Replies: 11
Views: 9590

OPA627 perhaps? it's quite good, also consider the Nelson Pass B1 buffer, ridiculously simple, and excellent, i'm using the more complicated DCB1 version with discrete shunt regs and no coupling caps, sounds amazing! circuit below, actually it's not exactly the circuit, but Pass's own schematic comp...
by grog
Fri Sep 13, 2013 3:34 pm
Forum: Buying and Selling
Topic: Wanted: pair of 5687
Replies: 3
Views: 3447

Wanted: pair of 5687

as per title,
looking for a pair of 5687 or equiv.
prefer modest, sensible priced over high cost fancy options.

thanks
by grog
Tue Sep 10, 2013 6:26 am
Forum: Valves
Topic: business trip toUSA, recommend some valves to bring back
Replies: 0
Views: 2285

business trip toUSA, recommend some valves to bring back

as per title, i'ff off to the USA for a few days, i'm thinking of bringing back some audio goodies, typically i can't think of any of those cheap online shops in the US.... so what should i bring back.... i'm thinking of getting a rasberry Pi to turn into a squeezebox thingy. also i'm looking for so...