DIY Audio Projects Forum
 NEW  Matt presents bias and operation data for the 6V6 tube in SE operation - 6V6 Single-Ended (SE) Ultra Linear (UL) Bias Optimization.

DIY Audio Projects Forum

Welcome to the DIY Audio Projects Message Forum. Use these forums to discuss Hi-Fi audio and to share your DIY Audio Projects. Registration is free and required to post messages and view the file attachments. Registration will only take a minute and registered users do not see any advertisements. After you have completed the online registration process, check your email (including spam/junk folder) for the verification email to activate your account. New members are under moderation - so your posts will not be visible until approved by a moderator. See the Read Me 1st, Forum RULES and Forum FAQ to get started on the forum.

It is currently 20 Oct 2018, 11:22

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 35 posts ]  Go to page 1, 2, 3, 4  Next
Author Message
PostPosted: 08 Sep 2013, 21:11 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 4945
Location: Australia
Never sip wine and troll eBay. I purchased this kit while checking out other components on eBay. As you can see the brd. is about the same length as my pliers. The kit is all you get for your $48 and you need to add, power tranni, heat sink, case etc. The 6N3 works in differential mode with the +\- 45V from the PS. All PS parts are on the cct. brd. and speaker protection is included.

Not a kit for the beginner with the BOP and the sketchy schematic not always agreeing. Very small solder pads and lots of parts make the assembly of the brd. taxing. The amp should produce better than 80W pc and I will be using two power trannies in parallel to supply enough current at the required voltage. Why two I hear you ask and not one? Because I could purchase these trannies from work at staff prices but they were not up to the current required so two will give me a 320W tranni supply. More than enough capacity at a fraction the price of a single tranni if I had to source it else where.

The enclosure is a 2U 19" rack mount. The HS I also got from work just fits in. I will use a small mains filter and have three selectable RCA inputs.
Attachment:
CctBrd.jpg


This post has a file attachment. Please login or register to access it. Only Registered Members may view attached files.


_________________
Projects: "Lagoon" - tube preamp with cathode follower | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "retro-Hiraga" - Jean Hiraga Le Monster
Website: retro-thermionic


Top
 Profile  
 
PostPosted: 26 Sep 2013, 03:32 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 4945
Location: Australia
Completed the amp after suffering a few bouts of builders constipation. Sounds fine so far but I have just realized I can't use my stereo sub-woofers which were usually split off from the preamp. This being an integrated amp with no preamp split off. I may look to run the subbies from the speaker terminals. I am expecting a little more base here and my 2-awys go easily to 50hz so I may miss nothing.

Very pleased with the build both inside and out. Im getting neater in my very old age. Three switchable inputs on the back and 80 RMS pc makes this an easy to live with integrated.

Name of the amp you ask: "Number 9". You have to think Woodstock double LP to work this one out. Any clues?
Attachment:
cctbrd.jpg
Attachment:
Inside.jpg
Attachment:
Number 9.jpg
Attachment:
Number 9Rear.jpg


This post has a file attachment. Please login or register to access it. Only Registered Members may view attached files.


_________________
Projects: "Lagoon" - tube preamp with cathode follower | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "retro-Hiraga" - Jean Hiraga Le Monster
Website: retro-thermionic


Top
 Profile  
 
PostPosted: 26 Sep 2013, 07:36 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 4945
Location: Australia
if you are looking to purchase the brd. it is from findhifi : http://www.ebay.com.au/itm/Tube-6N3-Preamp-TDA7294-Power-Amplifier-Kit-DIY-80W-x2-/121063467216?pt=AU_Electronics_Audio_Amplifiers&hash=item1c2ff1e8d0

_________________
Projects: "Lagoon" - tube preamp with cathode follower | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "retro-Hiraga" - Jean Hiraga Le Monster
Website: retro-thermionic


Top
 Profile  
 
PostPosted: 26 Sep 2013, 17:02 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 4945
Location: Australia
As always the first few hours on any amp never reveals the true character of the sound. After about two hours the amp started to perform. Initially it was very grainy and a little harsh sounding but a few hours in the music started to flow better. Where my tubes amps reveal triangles, tambourines, bells and chimes beautifully these were a little more hidden and not as well defined. Violins sounded good, raw and earthy but just some of the more delicate sounds, which my tube amps reproduce with easy, appear a hidden. It's early days so things may well change over the next 50 hours or so.

_________________
Projects: "Lagoon" - tube preamp with cathode follower | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "retro-Hiraga" - Jean Hiraga Le Monster
Website: retro-thermionic


Top
 Profile  
 
PostPosted: 27 Sep 2013, 21:30 
Offline
Project Author
User avatar

Joined: 04 Jun 2008, 20:59
Posts: 3814
Location: Arizona, USA
Hi Mark, Nice build. With more wine the sound will improve without having to wait 50 hours. :D On the eBay bit... been there and done that. Sometimes it works out well, and then.....


Good listening
Bruce

_________________
Some of my DIY Tube Amplifier Projects:


Top
 Profile  
 
PostPosted: 27 Sep 2013, 21:39 
Offline

Joined: 20 Sep 2008, 19:49
Posts: 171
Location: Montreal, Canada
Very nice build Mark. It's easy to get tempted with e-bay...

May I ask you where you get these beautiful engraved nameplate, these really add to the look of all your build. Do you engrave the text yourself. Great job as always.

I heard that the 7293 sound quite nice, I didn't know about the 7294.

Rgds,
Iso

_________________
DIY SS Amp : LM3875 GC | TA2024 | TA2020 (AMP-6) | TA2022 | Amp Camp Amp | JLH
DIY Tube Amp : RH84 SE | 6V6 SET | 13FD7 SET (Chinook) | 807 UL SE | 6BQ5 Class A PP UL | 6LR8 SE
DIY Spkrs : Cyburgs Needle | MLTL (FE206E) | CSS EL70 BR | Open Baffle (Alpha 15A + FE206En) (in process...)
DIY Pre-Amp : MooseFET.
To come : MLTL (CSS enabled EL70) + more tube amp...


Top
 Profile  
 
PostPosted: 27 Sep 2013, 21:55 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 4945
Location: Australia
Isophon wrote:
Very nice build Mark. It's easy to get tempted with e-bay...

May I ask you where you get these beautiful engraved nameplate, these really add to the look of all your build. Do you engrave the text yourself. Great job as always.

I heard that the 7293 sound quite nice, I didn't know about the 7294.

Rgds,
Iso

I got friendly with the local engraver Geoff. I had trained his predecessor to produce exactly what I wanted in a name plate then he left the business. It took sometime before Geoff really got up to speed but now he likes doing my plates and does a fantastic job. We have become good friends. He only charges me $20 a plate regardless of what I want on it. But I buy about one or more a month from him. I print on paper what I want and take a photo with my phone camera. I SMS this to him and he tells me when I can pick it up. Usually only takes a day. He does them all by hand and a lot are quite stylish. The plates are solid brass with a sticky back.

Bruce: Most of the time the eBay purchases work out well. If I had of thought about the amp kit I may not have bought it. It was an impulse purchase but the amp sound very good so I'm happy. The amp has plenty of power and plays very loud with no stain. I get more congestion from the speakers but only when playing real loud. I have two friends with Quad speakers. It should drive them easy.

_________________
Projects: "Lagoon" - tube preamp with cathode follower | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "retro-Hiraga" - Jean Hiraga Le Monster
Website: retro-thermionic


Top
 Profile  
 
PostPosted: 01 Oct 2013, 08:59 
Offline

Joined: 05 Jun 2012, 13:10
Posts: 196
Location: Darboy, WI, USA
Neat project Mark.

Do you get those enclosures cheap at work? They are a pretty neat way to get something less bespoke/ more incognito looking. I like it.

_________________
Thanks,
Ross in Wisconsin


Top
 Profile  
 
PostPosted: 01 Oct 2013, 17:37 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 4945
Location: Australia
RossD wrote:
Neat project Mark.

Do you get those enclosures cheap at work? They are a pretty neat way to get something less bespoke/ more incognito looking. I like it.

Retail they are $AU109 but with staff discount they are a lot cheaper. These days they are really nice looking. Stippled charcoal though they are labeled black.

_________________
Projects: "Lagoon" - tube preamp with cathode follower | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "retro-Hiraga" - Jean Hiraga Le Monster
Website: retro-thermionic


Top
 Profile  
 
PostPosted: 01 Oct 2013, 18:45 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 4945
Location: Australia
It's nice to be able to lift an amp which doesn't try to rip your arms out of their sockets. I took Number 9 to Dave's place to drive his 400lb 6 foot dual 12" woofer Osborn's. They are really quiet efficient, up around the 92db mark. Dave's CD player\preamp is a La Fontaine, shockingly expensive, with a tube driver stage.

Number 9 drove the speakers with extreme ease and very deep and full bodied bass. Strangely the amp appeared to take an hour to warm up before both of us were really digging it!

Dave started the afternoon with his new 250W RMS pc bipolar SS amp. Number 9 couldn't match it in all-out bass aggression but if you had only heard Number 9 first you wouldn't know it. But when it came to mids and highs Number 9 was (to me) a clear winner. Dave's 250W monoblocks just didn't seam to have any finesse. A great Rock amp but when it came to Classical or vocals it was far too grainy, too course and (to me) unbearable.

10 out of 10 Number 9.

_________________
Projects: "Lagoon" - tube preamp with cathode follower | "retro-Oatley 6J6" - 6J6 push-pull headphone amp with OPTs | "retro-Hiraga" - Jean Hiraga Le Monster
Website: retro-thermionic


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 35 posts ]  Go to page 1, 2, 3, 4  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 9 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
DIY Tube Projects :: DIY Tube Amp Kits :: DIY Speaker Projects :: DIY Solid State Projects :: DIY IC / Op-amp Projects :: DIY Phono Projects :: DIY Cable Projects :: Hi-Fi Audio Schematics
© diyAudioProjects.com - Terms of Service - Privacy Policy