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 18 Sep 2019, 07:51

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 422 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6 ... 43  Next
Author Message
PostPosted: 28 Feb 2010, 12:25 
Offline
User avatar

Joined: 18 Feb 2010, 10:52
Posts: 86
Location: Menifee, California U.S.A.
Hmm,
Regarding the cap's. It looks like a trade-off.
To tell you the truth I am not sure witch way to go now with this information.
What do you think , any suggestions?
This will be my first kit and I would like the best of all worlds Sound, Quality, and Portability.
And yes I know, from an engineering standpoint. Nothing is free !
I might have to give this one some more thought...


Top
 Profile  
 
PostPosted: 01 Mar 2010, 00:09 
Offline

Joined: 25 Jan 2010, 09:18
Posts: 1
Hi,
Regarding the Caps (you mean the 220 uF right?)

there should be no problem for 12.5 mm, maybe with a bit of leg-bending but should fit quite ok on the 272A in my opinion.

I've changed the resistors to 1% Metal-foil type(after the tubes, because it is not amplified and rather static), installed an OPA2134 and it reduced the background noise. But using them with 32 Ohm headphones there is still some.

So my question would be if Silmics would give another improvement (I also wonder why there even are such big Caps in the Signal Path, maybe someone could give me some info on that)?

Another idea is to apply a higher Voltage to the Opamp to have more choice regarding this part.

Matt


Top
 Profile  
 
PostPosted: 01 Mar 2010, 02:08 
Offline
User avatar

Joined: 01 Mar 2010, 01:29
Posts: 5
Location: NJ, USA
I just put an order in to Oatley through their website for a K272. Reading previous posts, I guess this means that I'll be getting the original kit, not the newly revised one. I emailed paul@oatleyelectronics to ask whether that is the case.

Anyhow, I'm planning to use this device as a pre-amp in my audio system, which consists of an Onkyo DVD receiver/player with 6 pre-outs and 2 integrated amplifiers (Onkyo A-RV401 and Yamaha DSP-E492). While I do already have pre-amps as integrated components, obviously, I wanted to use this DIY preamp to boost the signal going from the DVD receiver to my integrated amps (long story). Will this *tube* preamp be compatible with the rest of my audio components, which are all *solid-state*? Or is this pre-amp intended to drive tube amps only?

Cheers
-Denis


Top
 Profile  
 
PostPosted: 01 Mar 2010, 06:23 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 5134
Location: Australia
Robbie7 wrote:
Do these new kits have a rev. number ?, so when I order the kit I would like to receive the newest kit available :thumbsup: .

Robbie7- I only have the old kits.

Guys - these Kits have put Oatley on the world map. They claim they ship near two kits a day all over the world, particularly Asia!!

Also I have used 470uf low ESR caps on the output with no space issues.

_________________
Projects:"retro2308" - chip based headphone amp | ”Calibre 834” - tube phono MM preamp | ”najah” - Raw 180W Tripath Class D power amp | "Icon" - Shuguang CV-181Z preamp


Top
 Profile  
 
PostPosted: 01 Mar 2010, 07:16 
Offline
User avatar

Joined: 15 Dec 2009, 17:28
Posts: 70
Location: Netherlands
mwhouston wrote:
Guys - these Kits have put Oatley on the world map. They claim they ship near two kits a day all over the world, particularly Asia!!

Stock up on JAN6418 tubes now, before they will be prohibitively expensive! :mrgreen:


Top
 Profile  
 
PostPosted: 01 Mar 2010, 10:35 
Offline
User avatar

Joined: 18 Feb 2010, 10:52
Posts: 86
Location: Menifee, California U.S.A.
Great,
Where can I go to buy it now and extra tubes ?
How many tubes do you suggest for spares, I am thinking (2) ?
I sent the e-mail previously for where to buy with up-graded parts, however I have not received an e-mail on that one, so I have been holding off. It may have been lost in cyber-space.


Last edited by Robbie7 on 01 Mar 2010, 10:52, edited 1 time in total.

Top
 Profile  
 
PostPosted: 01 Mar 2010, 16:09 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 5134
Location: Australia
Robbie7 wrote:
Where can I go to buy it now and extra tubes ?
How many tubes do you suggest for spares, I am thinking (2) ?
I sent the e-mail previously for where to buy with up-graded parts, however I have not received an e-mail on that one, so I have been holding off. It may have been lost in cyber-space.

I have spoken to the owner of Oatley, Branko, about the poor response to international e-mails. A few have bought the kits from me because they couldn't get a response from Oatley. Just keep trying.

I will e-mail Banko directly again to let him know others are trying to contact the company.

_________________
Projects:"retro2308" - chip based headphone amp | ”Calibre 834” - tube phono MM preamp | ”najah” - Raw 180W Tripath Class D power amp | "Icon" - Shuguang CV-181Z preamp


Top
 Profile  
 
PostPosted: 01 Mar 2010, 23:00 
Offline
Editor
User avatar

Joined: 28 May 2008, 21:53
Posts: 4579
Location: Winnipeg, CANADA
matt1234 wrote:
Another idea is to apply a higher Voltage to the Opamp to have more choice regarding this part.

A higher voltage, especially with the OPA chips will help quite a bit. The OPA213x sound good at +/-9V.

deniss wrote:
Will this *tube* preamp be compatible with the rest of my audio components, which are all *solid-state*? Or is this pre-amp intended to drive tube amps only?

Yes. Mark has used the kit as a preamp so he should be able to provide a few comments using it in this role.

_________________
[ 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: 01 Mar 2010, 23:28 
Offline
User avatar

Joined: 18 Feb 2010, 10:52
Posts: 86
Location: Menifee, California U.S.A.
Wow,
That's new information that I have not heard off.
Please post more information !


Top
 Profile  
 
PostPosted: 02 Mar 2010, 01:19 
Offline
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 5134
Location: Australia
Guys, this is where the designer has been quite clever: he uses the opamp chip (unity gain) as a driver. I use the OPA2134s for preamp specific use and the standard chip for HP drivers. The tubes cannot drive so the chip does all the grunt work.

You should have no drive problems regardless of power amp etc.

_________________
Projects:"retro2308" - chip based headphone amp | ”Calibre 834” - tube phono MM preamp | ”najah” - Raw 180W Tripath Class D power amp | "Icon" - Shuguang CV-181Z preamp


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 422 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6 ... 43  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: Alexa [Bot], kmakdaddy and 16 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