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Reference tube amp kit, <20 watts for under $1,000?

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Hi, I'm looking for a reference-grade tube amplifier kit to go with my soon-to-arrive TDA1543 Russian DAC kit.

Has anyone got suggestions?

I don't feel up to building an amp from scrach and would much prefer a kit form.

I don't need much power, 5-10 watts would be great, but 35 watts WOULD be nice if I could get it as I'm using Sanyo bass-reflex speaker enclosures.
 
reference grade amp mated to sanyo bass reflex speakers.

mmmm

Unhelpful I know, but still.

OK rethink. To be helpful.

Ditch the speakers and find something easy to drive with a relatively flat impedance curve. No amount of reference this or studio quality that with or without gold plated doodads will overcome a speaker with an impedance curve that looks like a topgraphical map of a Pyraneean mountain pass
 
reference grade amp mated to sanyo bass reflex speakers.

mmmm

Unhelpful I know, but still.

OK rethink. To be helpful.

Ditch the speakers and find something easy to drive with a relatively flat impedance curve. No amount of reference this or studio quality that with or without gold plated doodads will overcome a speaker with an impedance curve that looks like a topgraphical map of a Pyraneean mountain pass


Yeah I'm listening to them now and they sound absolutely dreadful and muddled, their only redeeming quality is the bass response, but that is fixed by a 12" sealed subwoofer underneath my desk here.

Moderator: Please delete thread, i'm going to go and look for some decent speaker drivers and make my own speakers.
 
You'll still need a nice amp after you make yuor speakers and George Anderson has a proven circuit in his 15W/CH PP EL84 Amp done on a PCB board for $35 or with parts to populate the board for a total of $100.

You pick your Output Transformers according to your budget, but remember the quality is what makes the sonics on a tube amp. You also have to purchase a suitable PS Trans, tubes and a suitable enclosure or diy a chassis.

He has a form on this site also with a long thread on it.

Dave Gillespie's EFB mod is recommended for most any EL84/6V6/7591/7868 PP amp for improved sonics and output tube life.

Info over at diytube under improved performance for the SCA35/ST-35 amp and also over @ audiokarma in the Fisher form for under the SA-101 PP EL84 amp rebuild by Dave with the EFB II mod on it.


Anyway diy will make it all affordable and easy to troubleshoot down the road.

Hope that helps!

Randy
 
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"Reference" and under $1000, don't (IMO) mix. OTOH, you can do a very good amp, with several different models as the point of departure, for $500 or less. Other posters have mentioned some good options. I'll grind my own axe and suggest an "El Cheapo" built with Dynaclone Z565 O/P trafos and triode/UL mode selection switches. That would yield "6" and "12" WPC, respectively.

BTW, is there a Triad Magnetics distributor in "Oz"? With the exception of the B- trafo, off the shelf Triad stuff takes care of the power "iron" requirements of "El Cheapo" builders residing in "240" VAC zones.
 

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You'll still need a nice amp after you make yuor speakers and George Anderson has a proven circuit in his 15W/CH PP EL84 Amp done on a PCB board for $35 or with parts to populate the board for a total of $100.

You pick your Output Transformers according to your budget, but remember the quality is what makes the sonics on a tube amp. You also have to purchase a suitable PS Trans, tubes and a suitable enclosure or diy a chassis.

Hope that helps!

Randy

Yes I found out about one EL84 amp yesterday and I took one look at the sticker price and bolted, this PCB style seems much more interesting.

I do want to cut corners anywhere I can because the chassis for me is going to be a huge expense, I can however get ahold of NOS tubes of any brand like no tomorrow (at special request from an uncle who has a huge collection), on the basis of a 'gift'.

I'm buying a USB to I2S transport this fortnight coming up and after thatn I will have to start saving up some cash for a pair of Frugel Horn Mk3 flat packs then, in about a months time or so, I might be able to buy a couple of components, get a piece of wood from Bunnings (hardware store), and start an upside down tube project.

Lets get this thing all down on wood first before I start hacking at an expensive chassis.
 
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"Reference" and under $1000, don't (IMO) mix. OTOH, you can do a very good amp, with several different models as the point of departure, for $500 or less. Other posters have mentioned some good options. I'll grind my own axe and suggest an "El Cheapo" built with Dynaclone Z565 O/P trafos and triode/UL mode selection switches. That would yield "6" and "12" WPC, respectively.

That sounds fine except I'm not confident enough to be doing point to point wiring at this point, even though I can drill the holes fine and put in plugs, wire up mains safely, I'm not confident enough to be laying out and preparing an entire amplifier's wiring from whats in my head atm, so a PCB 'turnkey' solution sounds more enticing to me at the moment, hence the original posts title of needing a 'kit'.

I was restoring my Marantz 2275, and I'm by no means abandoning it, but if I'm going to be going with Frugel-Horns later down the track then there is really not much point to spending $200 on the Marantz in capacitors and restoring it at this time as the Frugel-Horns will be my /only/ speakers in the house, and there is no way I'm hooking up them to a 2275 that can do 85wpc..

BTW, is there a Triad Magnetics distributor in "Oz"? With the exception of the B- trafo, off the shelf Triad stuff takes care of the power "iron" requirements of "El Cheapo" builders residing in "240" VAC zones.

Yes there is, I'm led to believe, digikey.com.au, but they will charge me $34 flatrate in postage for any item, from one capacitor to $200 worth, that might be worth considering.

Antek transformers however are a cheap place for me, I bought a 600wv 2x18v toroidal and never used it.

I've got a power transformer arriving today from home which has been sitting on the shelf for the last 10 years, I'll take a photo of it and post it here sometime today.
 
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I built the Elekit TU-879S ($589/kit) a little over a year ago. We've been using it in our family room since then. It's worked perfectly and sounds beautiful. I upgraded the coupling caps and the potentiometer and that improved on its already great sound. Hard to beat, considering the low cost, high quality fit and finish and excellent instructions. It has two source inputs and its own volume control, so you can use it directly with your sources. I later built an Elekit TU-875 preamplifier ($445/kit), which I like to use in front of the TU-879S, mostly because it provides a phono stage, but also because it plumps the sound a bit in a way that I like.

Associated equipment:

Speakers: Zu Audio Omen
Preamplifier: Elekit TU-875
Turntable: AR Turntable
Transport: Squeezebox Touch
DAC: Wyred4Sound MDAC
 
That sounds great and looks like just what I need.

I've been waiting 7 years to build an amplifier with a 6L6 & KT88 for a tube, and this might be what I'm looking for.

Except.. its a 120v mains unit, and I just sold a really excellent 200VA stepdown transformer *rollseyes*
 
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freax: Post in the Elekit Forum here at diyAudio about a 220V transformer. I think Victor can supply those as an option when you buy the kit. In fact, I think they come with 220V transformers by default and he has to swap them out for a 120v unit for North America. Just ask...he's very helpful.

Good Luck! The Elekits are easy and fun to build and sound great. Excellent value for the money.
 
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RE EL84 PP kit types:
You could use the Dynaco Z-565 output transformers from Triode Electronics @ $85 ea and the PS trans for $65 Tubes would be under $100 with JJ EL84's which are tough and would work well on most EL84 PP amps.

If you don't want to make your own chassis you could also use their chassis and complete ST-35 kit. It would also be a nice 17W/CH amp with the EFB mod mentioned.

Pete Millets Amp could be made to work with affordable Edcor PS and Chokes for the PS . It would give a very useful amount of power at close to 30W/CH

Just research the forms for more info. Google can be great. As for a diy chassis , use aluminium as it's easy to work with and put on a a simple wood base. Hammond also makes chassis with optional wood sides.

Just that the extra power will give you more headroom with more speakers. SE can suit different music than PP also.

Randy
 
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RE EL84 PP kit types:
You could use the Dynaco Z-565 output transformers from Triode Electronics @ $85 ea and the PS trans for $65 Tubes would be under $100 with JJ EL84's which are tough and would work well on most EL84 PP amps.

If you don't want to make your own chassis you could also use their chassis and complete ST-35 kit. It would also be a nice 17W/CH amp with the EFB mod mentioned.

Hmm if I do it I'd have to get the supplied chassis, something more fun than sweating over a hot power drill and lots of metal shavings.

The ST-70 kit looks very nice.

Hmm, I'll take a look at their site and think about it. Thanks for the heads up.
 
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beykQ.gif

Hmm

I do love the 12AU7...

Tho I might have to make a Bridge rectifier adapter to swap out the [FONT=Arial, Helvetica]5AR4 if I don't like the sound with my type of music. (Fast paced)

Or even better install a switch inorder to switch between the two types, Silicon & Tube Rectifiers.

A nice read: http://www.tnt-audio.com/ampli/dynaco2e.html

[/FONT]

  • DriverBoard : newEF86
  • CapBoard : ST70Capupgrade
  • PowerTransformer : Export 120/240VAC (PA521)(+$35.00)
  • OutputTransformers : Standard (A470 x 2)
  • Caps : Xicon
  • Tubes : With Tubes (+$129.95)
  • Chassis : TriodeChassis
  • Wire : Cloth Pushback
  • Kit/Built : Kit
Subtotal: $864.90
Shipping: $265.00
Tax: $0.00
Total: $1,129.90


Just so you ladies know who your sugar daddy is...

 
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The ST-120 looks even better....

tubes4hifi amplifier KITs page

Does anyone have a cheaper source?, I would really like to get underneath that $1,000 radar.

Might have to settle for the ST-35 anyway though because of power consumption issues :p

But my musical tastes beg for more power.

I can probably source a 5AR4 from my uncle... might even be a Mullard, a 12AU7 I've got in my back pocket, several infact, now I just need a pair of EF86's... then to buy a quad match set of JJ EL34's..

That right there would save me $129.95 now and make me spend $60 later on...

I don't really like JJ's anyway, I'd prefer EH tubes, dunno why I just like the funny looking face on the boxes/tubes.
 
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