Help with first Tubelab Build :) - Page 2 - diyAudio
Go Back   Home > Forums > Commercial Sector > Vendor Forums > Tubelab

Tubelab Discussion and support of Tubelab products, prototypes and experiments

Reply
 
Thread Tools Search this Thread
Old 15th August 2014, 02:24 PM   #11
zxx222 is offline zxx222  Europe
diyAudio Member
 
Join Date: Aug 2005
Location: b
I am running mine at 5k:8 ohm with mark audio pensils 10.2, that are rather inefficient and it is loud enough for me.
  Reply With Quote
Old 15th August 2014, 02:34 PM   #12
evanc is offline evanc  United States
diyAudio Member
 
Join Date: Sep 2009
Location: New Jersey. About 1 hour from NYC and 1 min. from the beach
My amp uses 45 output tubes..even less power then the 300b. How loud the system plays will depend on how sensitive the speakers are.

The electra print transformers were not too pricey. lead time was very reasonable for a made too order part. As the owner operator of a one man business I like to give my money to the little guy.

The choke added to the power supply at the r4 position is nice. less ripple and the ability to adjust the voltage by changing the value of c4. check out PSUD2 cool program dealing with power supplies.
Have fun...be careful.
Evan
__________________
http://www.evancotler.com
  Reply With Quote
Old 15th August 2014, 04:18 PM   #13
diyAudio Member
 
Join Date: Aug 2014
Hey thanks guys this is great info and
Really helpful ... I appreciate it
  Reply With Quote
Old 15th August 2014, 05:00 PM   #14
diyAudio Member
 
denny3249's Avatar
 
Join Date: Jun 2012
Location: The frozen tundra of Cheeseheadland....GO PACKERS !!!
Quote:
Originally Posted by Indigoblue14 View Post
Ok thank you... So with 3k I'll get the wattage
But my sound will be sacrificed. I am starting
To understand. I have never heard a tube amp
That was in the 6 to 7 watt range ..
Do these amps put out decent volume even
With a 5k? I know better not to let the
Wattage rate fool me because it's a tube.

I'm running 8ohm speakers ...
With the primary for the 300b tubes what's
The sweet spot. Is it better to push as much
Voltage as I can ?
It's not the impedance (8 ohm) of your speakers that's important, but how efficient they are... What is the db rating for them? The higher the db rating of your speakers, the easier it is for the amp to drive them. I listen to Klipsch speakers with a 94db rating, 5 watts will play ear ringing loud (Just ask my neighbors). Let's say your speakers are in the mid to upper 80's for db, then your 7 watt amp is going to have to work that much harder to get you the volume you'd like. I hope this makes sense to you...

Here's a quick explanation....
Speaker Efficiency

Last edited by denny3249; 15th August 2014 at 05:02 PM.
  Reply With Quote
Old 15th August 2014, 05:46 PM   #15
diyAudio Member
 
Join Date: Aug 2014
Yes that makes perfect sense
Mine are 90db at 8ohms

Thank you..
I'll start sourcing my parts
  Reply With Quote
Old 7th September 2014, 03:16 PM   #16
diyAudio Member
 
ranhaber's Avatar
 
Join Date: Jan 2013
Quote:
Originally Posted by Indigoblue14 View Post
Yes that makes perfect sense
Mine are 90db at 8ohms

Thank you..
I'll start sourcing my parts
I run my 300b with the James, have a Canton speakers that are also 90db.
Believe me, They can be very loud

Enjoy the journey
  Reply With Quote
Old 8th September 2014, 02:07 PM   #17
diyAudio Member
 
Join Date: Aug 2014
Thank you ....
I got sidetracked on this project and still need
To source my parts..

Does anyone know if there is another parts
List floating around out there other than the one
On the tube lab site??
I'm assuming I can just send that list to mouser
And be done with it but I guess I'm a tad picky
And I was going through each piece and looking to
Purchase higher end items.. However I'm sure the list
On tubelab is fine I'll just work with the mouser parts list.

The only thing I need some further advice on is the
Output transformer...

Do people prefer the "one electric" UBT-2
or UBT-3 ?
  Reply With Quote
Old 8th September 2014, 05:16 PM   #18
diyAudio Member
 
denny3249's Avatar
 
Join Date: Jun 2012
Location: The frozen tundra of Cheeseheadland....GO PACKERS !!!
Here's what George says on the tubes and applications page...
"Most 300B amplifiers operate at 350 to 370 volts and use a 2.5 K, 3 K or 3.6 K ohm load. This is the sweet spot for most 300B tubes, and provides about 7 to 9 watts. It is also possible to use a 5K ohm load for reduced power with better distortion and damping factor. 6 or 7 watts will result. Most users go for a 3K ohm OPT and about 360 volts of B+. Some also use a 5K ohm OPT and a B+ nearing 400 volts, this is my preference." You should be able to make a decision from that... decide what you want out of your speakers. I prefer Edcor OPT's myself. I've used them on several projects, no complaints. My Klipsch speakers have a secondary impedance of 6 ohms which Edcor offers on various OPT's... Also, I don't mind the wait while the xfmrs are made.

Half the fun, for me anyway, is going thru the parts list and shopping on Mouser's, as well as other sites, web catalogs... I get side tracked a lot and easily, but it's a good time and you just never know what you'll come across. I usually opt for the best parts I can find, because why spend the time building something and not have the final product be the best it can be.. I don't worry about whether it'll work or not, because after 50+ yrs. of experience, I know it'll work and I don't want to take it apart later to upgrade parts. So take your time, look up each part... it's all part of the diy experience.

Patience, Grasshopper....
  Reply With Quote
Old 8th September 2014, 07:17 PM   #19
diyAudio Member
 
Join Date: Aug 2014
Fantastic info!! Can't thank you enough!!
What edcor output transformers do you use?
Is there a model # so I can investigate that as a option?
I'll shoot you a PM

This is great and I appreciate the help all of you!
  Reply With Quote
Old 8th September 2014, 08:19 PM   #20
diyAudio Member
 
denny3249's Avatar
 
Join Date: Jun 2012
Location: The frozen tundra of Cheeseheadland....GO PACKERS !!!
Here's the link to Edcor... there are many choices available, depends what you want to spend. I used the GXSE15-6-5K for my SSE... they were a great match for my Klipsch speakers...

Edcor Single Ended OPT

The One Electron xfmrs you are looking at don't have UL taps, so if you're planning on using UL with your amp...
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
My first build tubelab SE Indigoblue14 Tubes / Valves 1 14th August 2014 03:20 PM
Tubelab SPP Build sirrobin4ever Tubelab 9 4th March 2014 07:34 PM
My Tubelab SSE build; looking for some recommendations djherse Tubelab 20 6th January 2014 08:51 PM
*my* Tubelab SE build... oldmanStrat Tubelab 139 13th July 2009 08:03 PM
Another TubeLab SimpleSE Build nic6paul Tubes / Valves 91 13th June 2009 04:16 AM


New To Site? Need Help?

All times are GMT. The time now is 10:37 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2