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 17 Oct 2018, 08:07

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 131 posts ]  Go to page Previous  1 ... 10, 11, 12, 13, 14  Next
Author Message
PostPosted: 11 Sep 2012, 14:38 
Offline

Joined: 11 Sep 2012, 14:26
Posts: 7
Location: BRASIL
I'm new here and I'm from Brazil, I saw this project and will mount, 2 questions, I will use the output of your PC to the amplifier gain is enough? I saw someone talking capacitor of 0.02 would not be good for a good frequency response, which would be ideal for this value appreciate the help.

mauricio :up:


Top
 Profile  
 
PostPosted: 22 Sep 2012, 15:17 
Offline
Project Author
User avatar

Joined: 14 Oct 2008, 17:35
Posts: 901
Location: Dartmouth, Nova Scotia
Hello Karmau, the preamp has very high gain, more than enough for a computer to sound card to drive it. The coupling capacitor can be anything from 0.1MFD to a value as large as 2MFD, this should allow for a good frequency response on the low end.

Also, I recommend using a 100K input pot to control the input volume ;)

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


Top
 Profile  
 
PostPosted: 23 Sep 2012, 16:42 
Offline

Joined: 11 Sep 2012, 14:26
Posts: 7
Location: BRASIL
thanks for the tips

mauricio


Top
 Profile  
 
PostPosted: 05 Mar 2013, 21:51 
Offline

Joined: 28 Feb 2013, 13:03
Posts: 2
Hello,

Thanks for sharing this. I am seriously consider building it so as to warm up my home recordings. I am using an M-Audio Fast Tracks Pro and I do want to have some processing at the recording stage so I am planning to use this via the insert jack in the Fast Tracks Pro.

Actually I will build an optical compressor and an optical limiter (all solid state, op amps) and I would like this 12AU7 preamp in between. I am thinking that a 100k gain pot (at the input) and also a 100k volume pot (at the output) should work well for interfacing with the mentioned devices.

I would also like to add a simple 3-band EQ so as to be able to tailor the sound a bit. Is there a circuit you would recommend? Where should I insert it? In the tone section of the original 12AX7 schematic maybe?

Thanks in advance for any help.

David


Top
 Profile  
 
PostPosted: 05 May 2013, 23:53 
Offline

Joined: 05 May 2013, 23:48
Posts: 2
While looking at the schematic that is at the top of the preamp page i see that pin 9 is just hanging out there. Can someone tell me where pin 9 connects? I thought ground but better to ask first. Thanks


Top
 Profile  
 
PostPosted: 07 May 2013, 05:02 
Offline

Joined: 12 Mar 2013, 06:07
Posts: 86
Location: Thunder Bay On.
pin 9 is a center tap for the heaters and dose not connect any were. pins 4 and 5 connect to the 12.6 volts for the heaters


Top
 Profile  
 
PostPosted: 07 May 2013, 10:21 
Offline

Joined: 05 May 2013, 23:48
Posts: 2
kitchi wrote:
pin 9 is a center tap for the heaters and dose not connect any were. pins 4 and 5 connect to the 12.6 volts for the heaters

Very good. Thank you.


Top
 Profile  
 
PostPosted: 23 Jun 2013, 20:22 
Offline
Project Author
User avatar

Joined: 14 Oct 2008, 17:35
Posts: 901
Location: Dartmouth, Nova Scotia
Davidmochen wrote:
Hello,

Thanks for sharing this. I am seriously consider building it so as to warm up my home recordings. I am using an M-Audio Fast Tracks Pro and I do want to have some processing at the recording stage so I am planning to use this via the insert jack in the Fast Tracks Pro.

Actually I will build an optical compressor and an optical limiter (all solid state, op amps) and I would like this 12AU7 preamp in between. I am thinking that a 100k gain pot (at the input) and also a 100k volume pot (at the output) should work well for interfacing with the mentioned devices.

I would also like to add a simple 3-band EQ so as to be able to tailor the sound a bit. Is there a circuit you would recommend? Where should I insert it? In the tone section of the original 12AX7 schematic maybe?

Thanks in advance for any help.

David


I don't know what to recommend in terms of a 3-band eq, but this one would work: http://www.zen22142.zen.co.uk/Circuits/Audio/3band.htm

Then I would use a 100K pot at the input of the tube preamp but remove the second stage of the tube preamp, otherwise there are ways that you could integrate the EQ in between the two stages of the tube preamp but doing it right is past me at this point. ;)

Sorry for the wait :sleep:

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


Top
 Profile  
 
PostPosted: 28 Jun 2013, 11:34 
Offline

Joined: 28 Feb 2013, 13:03
Posts: 2
CrazzyAbtTubes wrote:
[

I don't know what to recommend in terms of a 3-band eq, but this one would work: http://www.zen22142.zen.co.uk/Circuits/Audio/3band.htm

Then I would use a 100K pot at the input of the tube preamp but remove the second stage of the tube preamp, otherwise there are ways that you could integrate the EQ in between the two stages of the tube preamp but doing it right is past me at this point. ;)

Sorry for the wait :sleep:


Thanks a lot for your kind reply. I might try this out.

However, I have a couple new questions. I take it that Rev. 2.0 of both preamp and PS are correct and will use them for the build.
I am thinking of an output volume, which would be symmetrical to the input gain (i.e. a 100k pot wired to GND after the output capacitor). Is this feasible?
About the 220K resistor (100K in Rev. 2.0) connecting pin 7 to GND: If a stick a variable resistor in parallel (hence allowing more of the signal from Pin 1 to flow to GND), could this be used to "tame" the gain?

Thanks again,

David


Top
 Profile  
 
PostPosted: 12 Jun 2016, 20:53 
Offline

Joined: 28 Mar 2014, 01:20
Posts: 1
any new updates latley ? Additions ??

vince
simplefx


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 131 posts ]  Go to page Previous  1 ... 10, 11, 12, 13, 14  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: Google [Bot] and 10 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