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 19 Aug 2018, 10:39

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 14 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: First time DIY tube amp
PostPosted: 26 Jan 2009, 15:05 
Offline

Joined: 26 Jan 2009, 14:21
Posts: 5
Hello. New here. I'd like to get into tubes and spend less money, so DIY seems to be the way to go. I'd like to start with something simple that will produce a decent amount of power. I mean ~10 watts. I know it takes many tubes to produce the wattage of a less costly SS. I like the KT88 SE design. ( http://diyaudioprojects.com/Tubes/KT88/ ) It looks relatively simple, fewer parts means less money, and the KT88/EL34 should produce a nice amount of power. Are there any other design suggestions you guys recommend?


Top
 Profile  
 
PostPosted: 26 Jan 2009, 18:30 
Offline

Joined: 26 Aug 2008, 20:57
Posts: 415
Location: Atlanta
Hey Cloud, welcome over here!

I would highly recommend building a low cost kit prior to stepping into something as big as a KT88 SE amp...why? Because even though it has few parts it has a few parts that are not cheap...Look at over $200 for the transformers alone...

The 6T9 can be built for around $200 and give you a good learning experience.

Alternatively you can take it niiiice and sllloooow on the KT88.

Whatever you decide, best of luck!!


Top
 Profile  
 
PostPosted: 26 Jan 2009, 18:49 
Offline

Joined: 26 Jan 2009, 14:21
Posts: 5
Are you referring to the James 6123H? I saw that they are expensive, but the one's I found don't look like those in the picture. I emailed the guy who made the amp to see about this and asked if he knew of a less expensive alternative.


Top
 Profile  
 
PostPosted: 26 Jan 2009, 19:08 
Offline

Joined: 26 Aug 2008, 20:57
Posts: 415
Location: Atlanta
The top of the line Edcors are $90 a piece and if they are better than the cheapy 30 dollar ones I have then they will be spectacular.


Top
 Profile  
 
PostPosted: 26 Jan 2009, 22:07 
Offline
Editor
User avatar

Joined: 28 May 2008, 21:53
Posts: 4559
Location: Winnipeg, CANADA
There have been a lot who have been happy with that SE KT88. You will want to use good iron which will be the major cost. You can save some using EL34 and a SS power supply.

_________________
[ DIY Mains AC Power Cable Cord ] - [ Gobo LM1875 Amp Kit ] - [ Tang Band D4-1 Horn Speaker Kit ] - [ Monoblock Push-Pull KT88 Tube Amp Kit ]


Top
 Profile  
 
PostPosted: 27 Jan 2009, 16:32 
Offline

Joined: 26 Jan 2009, 14:21
Posts: 5
The OT on this schematic is 5k ohm primary and 8 ohm secondary?

Image


Top
 Profile  
 
PostPosted: 27 Jan 2009, 19:32 
Offline
Editor
User avatar

Joined: 28 May 2008, 21:53
Posts: 4559
Location: Winnipeg, CANADA
CloudStrife, you will want the primary to be 5k. The secondary should match the impedance of your speakers. Another option is to get a audio output transformer that has multiple secondaries (4-8-16 ohms).

_________________
[ DIY Mains AC Power Cable Cord ] - [ Gobo LM1875 Amp Kit ] - [ Tang Band D4-1 Horn Speaker Kit ] - [ Monoblock Push-Pull KT88 Tube Amp Kit ]


Top
 Profile  
 
PostPosted: 27 Jan 2009, 19:41 
Offline
Project Author
User avatar

Joined: 14 Oct 2008, 17:35
Posts: 901
Location: Dartmouth, Nova Scotia
The Hammond units support 16, 8, and 4 ohm taps, but there SE trannies cost over $120 each! :hot:
Unless you have the money, go for it! They are capable of up to 30 watts! :up:

_________________
My Mini 12AU7 Tube Preamp, Pioneer SX-D7000, JVC XL-V221BK, JBL L80T, DCM TF700


Top
 Profile  
 
PostPosted: 27 Jan 2009, 21:04 
Offline

Joined: 26 Jan 2009, 14:21
Posts: 5
Would the same OT function with the modified version of this schematic? (the one listed on the website)


Top
 Profile  
 
PostPosted: 27 Jan 2009, 21:13 
Offline
Editor
User avatar

Joined: 28 May 2008, 21:53
Posts: 4559
Location: Winnipeg, CANADA
CloudStrife wrote:
Would the same OT function with the modified version of this schematic? (the one listed on the website)

It has a tap at 43%.

_________________
[ DIY Mains AC Power Cable Cord ] - [ Gobo LM1875 Amp Kit ] - [ Tang Band D4-1 Horn Speaker Kit ] - [ Monoblock Push-Pull KT88 Tube Amp Kit ]


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 14 posts ]  Go to page 1, 2  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 12 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