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Review of New S-5 K-16LS Kit

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andrejg,

If you are using SS rectification you might try a snubber (10nF cap in series with a 10R resistor) across each diode.

The resistor value may need to be adjusted up to achieve best suppression of switching noise.

thanks, i'll look into that. though since i replaced the stock rectifier with four uf4007 diodes and the capacitors with larger ones the hiss is audible only when you're closer than, say, 10cm from the speaker (at a normal listening volume). it is very much audible when the volume is increased to about 50%, but then the music is much too loud to be enjoyable.
 
Tube Rectifier

Here's what I did for tube rectification on my 16ls amp. The rectifier tubes are 6BY5GA television damper diodes. If you choose to go this route with your kit you must replace the first capacitor in your amp with a lower value as the TV damper tubes cannot handle anything over about 50 uF. I paralleled 2 of these tubes for half of a hybrid bridge and used ss diodes for the negative half. This hybrid setup did not drop the voltage too much so the stock power transformer can stay in service. The result is less switching noise and a nice slow ramp up of the B+ instead of blasting cold tubes with the full voltage before they can warm up.

Overall I love the tubes in the back because they look cool and make for great sound.

Just remember, check everything twice. Then check it again because you can't put the smoke back in after it comes out!
 

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caps and tube rectifier

Hi all

QUOTE:
Bigger filter caps (220 uF, 220 uF, 100 uF instead of 220, 100, 22)


so basicly all 100 are replaced with 220 and all 22 with 100?
For the tube rectifier; it doesnt do anything for your sound - it's only for at slow start of the amp tubes?

br. d.loncar
 
S5 16LS Amp Kit

Hello,
I am planning building a S5 Electronics 16LS amplifier. I see it has no Output for headphones. I presently have AKG 600 ohm phones.

Can anyone recommend a headphone amp kit I can add to the 16LS package, perferrably tube type?

Thank you everyone.
 
S5 16LS Amp Kit

Thank you andfejg, for the reply. I have been in contact with Larry at S5 and he recommended I could tap directly in the 16LS " A 220 ohm resistor in series with each speaker out (read wire) to corresponding headset speaker and the common to ground (one of the black wires). You could do this externally or internally to a jack for the head phones. "

How do you (or any other owner) like your 16LS and did you make any changes or additions to improve your perception of the sound quality?

Again thanks.
 
is this a similar design ?
tho it does not come with trafos, I wonder if it would be a good EU-alternative :scratch2:

Dantimax (elektronik) - Tube_pre-_-_poweramps
i've had my eye on their kits for a long time, especially the tube preamps. if you look carefully they have the appropriate transformers for their kits (and a bunch of other stuff) listed in the parts and accessories section. if i had found their site before i found about the k-16ls i would have probably bought their kit. even if just to avoid import taxes and duties (and taxes on shipping costs and taxes on taxes :mad:).
perhaps one day, when money's not so tight :D.

(is it just me or does the thread subscription work in a weird way? i've set it to instant notification, but most of the time i don't receive any notifications?)
 
I just bought and built this kit as well. I built it stock with the exception of using Orange Drops for the coupling caps and putting snubbers across the filament pins of all tubes. I also twisted the filament wires from the power transformer to the baord (as directed in the instructions). This amp sounds great and there is no hum what so ever. I plan on upgrading the OPTs to the EDCOR CXPP25-8-5k and changing out the rectifier to four UF4007 diodes with cap/resistor snubbers across each one. I would also like to try a UL configuration with the new EDCOR OPT - has anyone tried this? HOw did it work?
 
Thank you all for this excellent thread. I have built two amp kits already and just ordered the 16LS today. I'm going to be putting in the larger electrolytic cans (getting quality ones too), doing orange drop caps and the good mica caps. A couple of questions:

1. I am going to be running 4 ohm speakers with this. I hear the output transformers included with the kit are crap. The Edcor iron recommended in this thread is for 8 ohm output. Does anyone have a usable 4 ohm quality transformer for this application?

2. Are there any tube upgrades? Some other beam tetrode that is more powerful or better sounding?

Thanks for your help.

Also - I've been looking at the Edcor CXPP30-MS-5K as a replacement to run 4 ohm speakers, would this work?
 
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The Edcor CXPP30-MS-5K should work fine. On my K16 I upgraded the coupling caps to Orange Drops and the PS caps to JJ caps. I am not sure the ODs helped any but the amp is very quiet with no noise or hum so i am very happy with the power supply. I do not know of any upgrade to the power stage tubes but these in the kit are fine at normal listening volumes. Turn it up however and you will hear the distortion - past 12:00 is not good. Overall it was a good kit to start with but left me looking for more. So now I am in the process of building the Podwatt 2C DIY now. A bit less power in theory but I think it will sound much better when done.

My speakers are Nuance Series 5 units with 89 dB/w sensitivity and the listening area is not large ~120 sq ft.
 
Hi everyone,

I know I'm resurrecting an old thread, but my friend is having issues with his K-16LS amplifier. There is a constant buzz on the left channel -- even if there is no input -- and a slight buzz on the right channel.

I'm fairly familiar with electronics, although my tubes knowledge needs brushing up.
There seems to be a steady buzz out of the left channel. I suspected it was a faulty output transformer, but after swapping it with the right channel, the buzz persisted. However, touching the transformer chassis reduced the buzz.

The next thing I checked was the common grounds, and everything seemed to check out fine. (I didn't do an extensive check, due to time).

Finally, I'd arrived at the input transformer, which is where I'm at now. Is it possible that one of the HV caps (c10, c11) is kaput and is causing the buzz? I haven't tried removing/replacing it yet? I am also hoping to add VoltSecond's mod before the rectifier circuit.

Any help/reading material would be useful and appreciated.
 
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