DIY Audio Projects Forum
 NEW  Bruce Heran outlines the details and construction of his simple DIY 6DJ8 (ECC88) Tube Hi-Fi Headphone Amplifier Project.

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 01 Aug 2014, 23:27

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 72 posts ]  Go to page Previous  1 ... 4, 5, 6, 7, 8  Next
Author Message
PostPosted: 23 Aug 2011, 14:50 
Offline

Joined: 05 Aug 2011, 15:55
Posts: 15
That actually cleared a lot of things up. It really puts a lot of things in context. Given that I get that now, do you have any specific suggestions for any high sensitivity 2 way bookshelf speakers that are pre built and under $400?


Top
 Profile  
 
PostPosted: 23 Aug 2011, 22:55 
Offline

Joined: 03 Jan 2009, 10:44
Posts: 121
Speaker selection is a totally subjective thing. Your ears are not like anyone else's. I suggest you go to a reputable high end stereo store and listen to different speakers. $400 should take you pretty far for bookends.

If this doesn't appeal to you then go to the speaker forum on this site. Lots of good information there.

Have you decided on the K-12G? If so, you have lots to study and parts to collect if you want to get that build just right...speakers aren't much use without an amp.


Top
 Profile  
 
PostPosted: 24 Aug 2011, 00:26 
Offline

Joined: 05 Aug 2011, 15:55
Posts: 15
I have although I am unsure about that vs. the K - 502. Any huge reasons this would be a better option? Also, could we get together a list of the simplest and easiest and most efficient alterations after market that a beginner would make to either to improve sound quality? Specific values and places to get them would be amazing. Once the final amp is picked I plan to order that and the speakers and post pics as I go! :D


Top
 Profile  
 
PostPosted: 24 Aug 2011, 11:35 
Offline

Joined: 03 Jan 2009, 10:44
Posts: 121
For the K-12G modifications, see the following:
http://diyaudioprojects.com/Tubes/K-12M_bh/

In the projects section there is another report from Gio which I found useful...it's the first project in the tubes section. Be sure to get the report from Voltsecond.

Most everything you need to know (and probably more) can be found in this site, but you'll need to do some digging. Search the forum section and read each thread. Take lots of notes. I got confused once or twice but eventually sorted it all out and am very pleased with the results.

I don't where you're located so suggesting supply sources is difficult. If in the USA, I use Allied Electronics for routine stuff (enclosures, etc.). For tube amp components, I like TubeDepot. They'll have the various capacitors and such you'll need and have really fast shipping. For the suggested upgrades, I doubt Radio Shack will have what you need.


Top
 Profile  
 
PostPosted: 24 Aug 2011, 12:18 
Offline
User avatar

Joined: 05 Nov 2010, 21:07
Posts: 655
Location: South East US - Tennessee
Other sources for US area are:
DigiKey
Mouser Electronics
Antique Electronics Supply

DigiKey and Mouser carry lots of discrete components (resistors, capacitors), cases and the like. They even carry some of the HV transformers and output transformers, but not alot.

Antique Electronics Supply carries a lot of specialty products for tube amp construction / restoration, but they don't have a large selection of anything - about like TubeDepot. I like to shop the two because one may have better pricing than the other.

_________________
The key to a successful build is to keep the smoke IN the circuit.
-Les

Science without religion is lame, religion without science is blind. - Albert Einstien
_________________________________
LM380 Bridged Guitar Amp, Oatley K301 Phono Pre-amp, Oatley K272 Headphone Amp, Tube proto-board
Current project: 6V6 "pseudo Champ" prototype
Still to come (On hold): 6CG7/12AX7 Guitar amp (modified FireFly)


Top
 Profile  
 
PostPosted: 24 Aug 2011, 14:32 
Offline

Joined: 05 Aug 2011, 15:55
Posts: 15
I am pretty settled to actually start ordering and building :D. The K-12G it is. Step 2 is probably ordering Klipsch B-2 or B-3 or RB-61. However, my biggest question is are there any mods that were done to the M model that have been fixed in the design of the G model? For example, I have heard numerous times that the tranfo issue was fixed between the two.


Top
 Profile  
 
PostPosted: 24 Aug 2011, 17:50 
Offline

Joined: 05 Aug 2011, 15:55
Posts: 15
Does the K-502 address any of the issues people are modding the K-12G to fix???

I am wondering if I am better off getting the K-12G and spending the time getting different caps, adding snubbers, changing the tranfo, etc. or just getting the K-502 and maybe changing the pot and just upgrading the caps.

The speakers I am buying to go with this are the Klipsch RB-61's which have high enough sensitivity for me (> 94 dB), especially for a small apartment bedroom.


Top
 Profile  
 
PostPosted: 25 Aug 2011, 12:57 
Offline

Joined: 03 Jan 2009, 10:44
Posts: 121
I think the K-12G transformers are ok. Capacitor upgrades and additions, as well and adding diodes are a good idea for either amp. There's more documentation regarding the K-12 on this site, however, so I'd stick with that one, IMHO.

You can, by the way, get a chassis for the K-12G from the amp's manufacturer:

http://www.s5electronics.com/gcase.html

It includes chassis and vented cage, a big improvement over the plain board.


Top
 Profile  
 
PostPosted: 25 Aug 2011, 16:40 
Offline
Project Author
User avatar

Joined: 04 Jun 2008, 20:59
Posts: 2330
Location: Arizona, USA
Hi, I would get the K-12 as well. I used mine for many hours and it is still operational. The S5 case is really quite nice, not cheap, but well designed and made. But if you are skilled with metal, wood or plastic you can roll you own and personalize it. If I had to choose on thing to do to the K-12 ....that would be replace the standard coupling capacitors with ones of better quality. It made the most noticeable difference in mine. Cleaner B+, better output transformers and other things helped, but not to the same extent. BTW you generally do not need the capacitors at the input stage. So you really only need 4 new ones. None of my equipment have capacitors in that location and all work fine (none of my commercial designs have them either). At one time you used to run into equipment (like CD players and such) that had more than trivial dc potentials mixed in with the output signals and the capacitors would block the dc and prevent problems with the input stage of amplifiers. I have not seen anything in quite some time that has that problem as most manufacturers place capacitors on the output side of the devices to prevent the problems.

Good Listening
Bruce

_________________
Some of my DIY Tube Amplifier Projects:


Top
 Profile  
 
PostPosted: 26 Aug 2011, 00:03 
Offline

Joined: 05 Aug 2011, 15:55
Posts: 15
Two K-501's it is. This will keep stereo separation as well as take care of the tranfo issue.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 72 posts ]  Go to page Previous  1 ... 4, 5, 6, 7, 8  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: Bing [Bot], Google [Bot] and 2 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:  
cron
DIY Tube Projects :: DIY Tube Amp Kits :: DIY Speaker Projects :: DIY Solid State Projects :: DIY IC / Opamp Projects :: DIY Phono Projects :: DIY Cable Projects :: HI-Fi Audio Schematics
© diyAudioProjects.com - Terms of Service - Privacy Policy