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1st tube project, tubalizer?

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Recently i decided to make an iPod amp and became interested in tubes. I am planning to power the preamp & amp off a single 12v sla battery, if I used a tubalizer, would i be able to power both the tubalizer and power amp form the same battery.
Also, if anyone has any suggestions regarding amps it would really help(i wouldnt mind making a tube power amp but a bit hard with only 12v), i am using 2*10watt rms 8ohm speakers.

thanks
 

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Tubalizer is a dud

See this thread
http://www.diyaudio.com/forums/showthread.php?s=&threadid=89195&highlight=

A search will turn up a couple of other threads on this dubious device.

Basically its a dud. Tell us what you are trying to do, that is, are you just looking for something to go between your ipod and a Solid Stae Amp to give it a bit of tube warmth? or what?

Then we can give you some advise on alternatives.

Cheers,
Ian
 
Hi Luke.
I drew the schematic (I am S3) that you posted and I've recently found an error in it. I can't remember exactly what it was but I can check it later. PM me if you're in a hurry!

I only noticed when I removed all the electrolytics to upgrade it to 24V operation. Sorry for any confusion. It was my first tube 'project' also.

I wouldn't like to discourage anyone from making one. I had major problems with mine but I have heard of some people enjoying them. I'd definitely keep mine (running on 24V) for musical instrument use. It's more of an effects unit than a piece of Hi-Fi kit IMHO. I increased the voltage from 12 - 24V and that prevented the clipping I was experiencing but the sound was just very vague. My system is ruthlessly accurate (bright, detailed and fast transient response) in the mids and treble and the tubalizer just smeared everything. But .... I did get that valve 'psychoacoustic' effect that melts your heart. The trade off just wasn't worth it with the tubalizer.

Also notice that most of the negativity about the tubalizer is from me! and that others are usually saying that it shouldn't work on 12v and that it is very expensive to buy (considering the parts cost to DIY).

Alastair E's low voltage design is too easy to ignore and great fun. I have made a few but have never tried it with the valve that he recommends. It's in the same thread as the tubalizer stuff.

The 24V Aikido gets very good press and is definitely next on my 'hitlist'. Quite importantly for some (and me) boards are available to buy. I haven't heard it myself though.

Cheers,
Martin:)
 
I have tried the design I outlined in those threads, with the 9V batt, but instead of in the 'earthy/cathode circuits, I put it in series with the anode circuits. I have some small glass wire-ended (6C3B-V) valves that do need that little extra before they perform, although some examples work well at just 12V

The ECC88 or 6DJ8 works very well, but of all the valves Ive tried, I like the 7586 Nuvistor in this amp at 12V. The Russian 6C51H-B versions I have sound just great and are not microphonic (Yet!)--Got them cheap on fleabay....

Basically although you are still using a 12V supply, the additional batt in series with the 12V supply raises the 12v to 20 odd volts, for the anode circuit to great effect More headroom and a little more 'dynamic' The 9V batt should last well, as only a couple of mA drain for a two-channel 'stereo' pre-amp (The Heaters are supplied directly from the 12V 'main' supply) My current bread-board (Single-channel) has been powered continuously for around a week or so now, and the 9v batt still reads 8.5V....:D

The 12V is supplied by a golf-cart SLA on 'mantainence' or float charge;)
 
thanks for all the help i checked out ebay and found this---

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=160132788718

is that what im looking for? (dont want to spend 20 dollars on dud)

Also, i was wondering if there would be a specific way to power/wire all of the amps from the one battery --

2x tubalizers(alistairs design(with 9v battery)
1x ipod(into a 7805 regulator
2x amps still undecided on amps (please suggest one(10wrms 8ohm load)
 
Yup, thats the 6DJ8 or ECC88 valve. If at all possible, I would try and get new/NOS rather than used valves for this low-volts work, as you need as much emission as possible....

A valve with several hundred hours on it may still work and be well within spec at 150-200V but may be very weak at low volts...Just a thought....Maybe Im wrong...

Shouldnt be much of a problem running the valve stages and the ipod off common supplies with appropriate volt reg for ipod and maybe heaters too....



:cool:
 
6H8C Russian 6SN7 Analogue...

I have several of these valves, and found them pretty good...

They worked well in the scheme I posted and at just 12V....(Well, 13.6 lead-acid on charge...) Cheap and cheerful, these Russians are fairly good performers generally and great value for money!

All according to your set-up, the gain you need, and the signal level, you may well not need the extra 9V batt in the anode-circuit. It makes life easier if you dont have the extra batt, but I suggest you try it both ways and see if there are any noticable changes to the sound using Your Ipod and Your amp etc.

For my application, a cheapie MP3 player, the '12V tube-amp' then into a Tripath TA2020, for the car I can get away with no extra batt, but when running the 12V tube amp into my OTL, during experimentation I definately found I needed the extra headroom, as my OTL needs just a little extra input for full output (Its overall gain was set with a pre-amp input in mind)...But its still pretty good at normal listening-levels

Experimentation is the name of the game....What works in my set-up may not be 'perfect' for yours but hey, At 12V, you can mess about 'live' and not risk life or limb!.....:D
 
i breadboarded the circuit (the tubes took a while to get) it makes the signal sound alot better, but i did get different voltages compared to your readouts (my battery wasnt on charge, only putting out around 13v) i got--

1--0.25v
2--8.41v
3--0.55v
4--3.93v
5--12.00v
6--4.34v

the circuit works but i thought i should check
thanks for all the help
any things i should note when mounting?

luke
 
is there any way in particular i should connect the ground points to each other, and then to the signal and other amp??

what sort of circuit board would produce best quality,
i have heaps of normal blank copper boards and those boards with the pre-punched holes and copper circles around each hole.
 
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