Wednesday, July 14, 2010

5687.. status

After few hours of ‘burning in’ this is what I found.

The microphony of the tube is very tube dependent! I have bought two sets of the 5687 tubes by Tungsol and so far have experienced less ‘microphony’ in one than the other one!

Somehow AC heaters induces more hum, as such DC heating is more favourable.

I have stopped playing with it and waiting for the dual 50uF+50uF which was originally specified to arrived. There is this low AC humming which I suspect coming from the B+ voltage as I have used a substitute caps of 20uF instead of the 50uF originally specified. I was desperate and need to get it running before deciding to get the expensive stuffs or not. The dual cap was bought from ebay and could take anything form 7-14 days to arrive. Item was bought last week..

Till then..

Friday, July 9, 2010


Had the opportunity awhile back to audition the infamous F5, 25W+25W pure Class A power amp in my system. It's DIYed by a fellow forummer. I bought the PCBs.. wonder if I should build one.
Here the pix:

If you're looking for a kickass Class A 'heat' monster, this is it! For Class A purist only. Should be able to satisfy full range lovers. Unfortunately at higher than 'normal' listening levels, my RTL3 is gasping for more 'air'..the 'thirst' that only the Technics that I have can satisfy... 'nuff said.

Wednesday, July 7, 2010

The good news and some 'bad' news..

Okay, the good news is, I have completed the tube preamp, hurrah!!! That was about a a week ago.
It was worth the wait (and the agony of waiting)! The preamp was connected to a discrete 40 watter (nicked name,D'Bomb) and the sound is simply marvellous albeit some issue which is irritating me right now.

One, I have humming issues, then buzzing then 'crackling' issues.. After much googling and reading more about tube amp designs.. I managed to solve the buzzing by opting to use DC heater as opposed to AC heaters. BTW, I have read and done all the do's and don'ts about tube amps building thingy, like wires crossing at 90 degrees etc.
The humming and 'crackling' although very soft and only audible when I am not playing anything, it is just 'psychological annoying'... Since I used some 'alternate' (read cheap and what is avail.) parts to what was being specified in the original design, now that I have heard how good it is and believing that there is a potential for it to become 'better'), I think it's worthwhile to invest in quality/premium parts and I have decided to buy the 'good stuffs' online.. I also found the TUNGSOL 5687 is kinda 'microphony' and it is known for that! There are other drop in replacement for this 5687 but I would not do it till further listening. Since this is my first tube project, I just want to have some experience and maybe moving on to other popular tubes. More updates later..

The casing used (like a metal pizza box) was bought cheaply from a manufacturer excess stock meant for something else.. hehe

Pic shown the preamp during the 'wet-run'. Speakers used was the Gale 3030 floorstander and I could not believe the amount of good solid bass coming out!

Saturday, June 26, 2010

A quickie- yes a short update

Its been awhile, I know. I have eventually received the last components about two weeks ago. They're the hard to find, 7 pin mini sockets! Now I actually have ALL the required parts including the casing for the preamp but whats holding me?
After looking at the project writeup and inputs from DIYers that had built the preamp, it looks like I have to use a good grade audio caps for the amp if I want it to perform.. it's gonna costs for sure but might as well do it right, right?
Hence I decided to hold it out a little bit longer till I acquire those parts...

Saturday, February 13, 2010

5687 preamp progress...

Took deliveries of two major components:

The main power tranny.. specially ordered that took about 4 days.

One of the two 30H@100mA chokes that is required for the B+ supply. Took delivery about 2 days ago from my usual supplier..

The only thing I am short of now is the tube sockets, a 7 and 9 pin but a friend has a set and will get that soon from him.. Then I can start to build this long awaited project..

Thursday, January 21, 2010

Cables,interconnects,plugs,sockets, do they make any difference?

This has been going on for ages! Some are a believer and spend a lot of 'mullahs' investing into the above tweaking and squeezing to get the last ounce/gram of 'perfection'.. I am not going to prove it or otherwise but of late I see no harm in  investing a few 'mullahs' just to see(hear) if there are differences.. I use differences here they may not amount to improvements at all! Any changes that satisfy my sonic needs will be classified as improvements..

I started awhile back by using/making my own speaker cables.. a really heavy gaged 14AWG conductor cables.. with a good high quality banana plugs I have compared with a commercial branded speaker cables.. I liked mine best!

I have made my own digital coax cables for my CD transport.. mini-to-mini cables for my headamp and headphones.. to name but a few.. but I want to draw your attention to my latest findings..

Based on some discussions in an audio thread in a local forum, I invested in a high quality MK 3-pin plug. The fuse is silver plated so are the fuse holders.. the wires in the plug are held by very solid binding posts!

I wasn't expecting much but the first half hour I begin to detect a very minor changes... microdynamics has 'improved' somewhat.. the low end is well rounded and the mid bass was really in focus! Midband/range is slightly projected and its kinda rough and edgy with a rough edge.. top end was some what well define but still within control.. as the minutes and hours ticked by, the rough edges has been trimmed somewhat.. I noticed the PRAT has somewhat picked up.. and I am not used to such a high speed.... I like my music slow and mellow..

Still in the mood of 'fine tuning', I took out the silver plated bussman fuse and replaced it with a 'no-name' fuse.. To my amazement, that has somewhat tamed the midband, polished and pushed back a little bit of the midband projection, still I am not satisfied... bear in mind, I am a bass head and liked my music relaxed.
The source of my music was my favourite CD: Sadao Watanabe- How's Everything. LIVE at Budokan. I have been listening to this album since 1980, and believe me I know every beat/note in every song! A SONY CD player was used feeding my DIY STK hybrid amp, powering my favourite speakers of all time, RTL3 made by TDL Electronics. A transmission line speakers that I am in love with and never looked back since!
Reviews here: RTL3 Review

I am going to give it a few hours to 'settle down' and may look into changing the 'normal' mains cable into something that was recommended in the threads..

Will update soon... Happy listening guys!

Saturday, January 2, 2010

Vinyl deep cleaning, using woodglue - The process.

The woodglue is applied using the flexible spatula provided. I poured about 1/2 cup worth of woodglue and while the turntable is spinning, evenly spread out the glue as seen. Honestly it's kinda thick, I should be using less woodglue as this would aid faster drying/curing... since this is the first time, its okay.. we learn from experience.. ;)

The processed vinyl is place on a stand and left on the dining table with the ceiling fan switched on, to further expedite the drying process. Since this will take a few good hours dependent on the thickness of the woodclue, I did this just after dinner, anticipating that the woodglue should be dry in the morning... 

This is what I found in the morning! From apaque thick white covering it became 'hard' and translucent layer, ready to be peeled.. The trick here is to use your finger nails and pushed the layer at the edge, it should peel easily..

There you go, what did I tell ya?! Start peeling from the edge and work your way to the center... then work your way circumferentially... simple! ;)

As you can see the woodglue layer is very flexible, its neither soft or hard. Almost there and I can see that the vinyl surface has transformed.. like its brand new!!!

Voila! A spanking 'new' vinyl is in my hand ready to be tested/played! A quick test on the turntable revealed a much quiter surface noise, very minimal pops/crackles/etc... The stylus is left clean as opposed to be full of gooey/gunk/whatnots after a few turns..

Now you're ready to do the other side!!!


Very effective in deep cleaning very dirty vinyls.. I found later if you were to initially wet the surface then apply the woodglue, it is more penetrative.. the woodglue that I used was water soluble...
You can also treat the vinyl with isophrophyl alcohol.. this is preferable if the surface is 'oily' and would aid the woodglue in going into the grooves...

Its a lengthy labourous process.
Labourous as the application need to be done manually and carefully. I suggest you try it out on old unuseable vinyls to get the hang of it before venturing on your precious vinyls.
Lengthy because it'll take a while for the woodglue to cure/dry, again depending on the amount being used and the type of woodglue being used. The one that I used take between 4-6 hours before it's 'peelable'...

Warning. Do this at your own risk. So far I had a 100% success rate and you should be able to. Good luck and have fun! I did...!

Happy New Year 2010!

Friday, January 1, 2010

New year resolution? Yeah right!

Here are kinda shortlist of what I am intending to do..

1. The 'lawn mower'(nick named by one of my forumer friend, thanks. Thats whats friends do...) aka know as Dunlop Systemdek will be getting the long awaited tonearm, offered by a close forumer friend. Its the RB300! After all these years (I remembered like 1988!) the Systemdek will be resurrected!

2. I have to find time and obviously the parts required to build up the tube preamp. Posted earlier I have bought 2 sets of tubes.. time to warm up the iron...

See? I told you it was short!.... LOL!

Happy New Year 2010!

Wishing everyone and may the new year bring joy, happiness and prosperity!