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 23 Jul 2019, 11:43

All times are UTC - 6 hours [ DST ]

Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2, 3
Author Message
PostPosted: 05 Jun 2019, 06:58 

Joined: 19 Oct 2018, 15:30
Posts: 126
Location: Montréal, Québec
mwhouston wrote:
Gab wrote:
Very nice build ! Must be very enjoyable to listen to something as silent as it seems to be. I wish my 4S preamp was as silent as this !

Try moving the earth wire. On one build I put the earth on the RCAs to stop the hum. In another I moved the earth to the pot and not the RCAs. By the earth I mean the negative of the HT.

If you have the mains earth connected to the HT negative try removing it if not try connecting it. And do that in combination with the above two connections. Generally don’t have two earth connections by that I mean don’t connect to the RCAs and the pot. Or if you haven’t try both. All this varies from one built to the next and there never seems to be a set way.

Thanks for your advices. I’ll try this tomorrow when i’ll receive my new rectifier. I have no idea how, but I broke the envelope of the one I had... I find ground loops to be very tricky to solve. I’ve been struggling with this problem for several months, but I haven’t been able to bring the noise to an acceptable level. I have built the power supply at least 4 times according to the original design with very little success. The best results I’ve had were with a chinese filter board instead of the original psu. Most of the noise I get is 120hz. I’ll keep on trying !

Back to your thread. I’m getting off topic with my noise problems, but really appreciate your inputs ! Thanks !

PostPosted: 20 Jun 2019, 19:57 
Project Author
User avatar

Joined: 06 Jun 2008, 18:23
Posts: 5115
Location: Australia
Astounded by how well “LeManja” worked I figured why not add a HP driver section to one of the best sounding and most expensive tube preamps I have built. This in no way effects the performance of the preamp and extends its use to a HP amp also. Listened for about 8 hours yesterday all afternoon and into the night and are extremely impressed. Cheap and easy to do and just adds extended functionality to the preamp.

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

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

Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 22 posts ]  Go to page Previous  1, 2, 3

All times are UTC - 6 hours [ DST ]

Who is online

Users browsing this forum: No registered users 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
© - Terms of Service - Privacy Policy