It is currently Mon Mar 16, 2020 10:06 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 137 posts ]  Go to page Previous  1 ... 4, 5, 6, 7, 8, 9, 10  Next
Go to page Previous  1 ... 4, 5, 6, 7, 8, 9, 10  Next
Author Message
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Wed May 04, 2011 4:23 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Mar 11, 2008 10:08 am
Posts: 9034
Location: Louisiana
Thanks for sharing your build of this beautiful amp Snowy!! Real fine job, instructional, informational, pictorial, and workmanship!! 8) :wink:


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Thu May 05, 2011 1:50 am
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Sat Mar 20, 2010 2:30 pm
Posts: 792
Location: A Land Downunder
Thanks a bunch fellas, it's a pleasure to put these build diaries together discussing different aspects of the build, I learn a lot from it and it's great to exchange ideas, I just hope people enjoy reading through it and checking out the pics. 8)

Snowy :wink:


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Thu May 05, 2011 2:32 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Fri Jun 20, 2008 11:08 am
Posts: 2265
Kick the tires and light the fires!!!!!


Damn good show

_________________
"Yesterday is history, tomorrow is a mystery, but today is a gift. That is why it is called the present."

oogway, kungfu panda 2008


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Thu May 05, 2011 3:26 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26417
Location: Tombstone Territory
No457 Snowy wrote:
Thanks a bunch fellas, it's a pleasure to put these build diaries together discussing different aspects of the build, I learn a lot from it and it's great to exchange ideas, I just hope people enjoy reading through it and checking out the pics.


Absolutely!

You're an artiste, Sport!

8)

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Thu May 05, 2011 8:53 pm
Offline
Amateur
Amateur

Joined: Fri Aug 27, 2010 9:31 pm
Posts: 171
Sound samples please! with guitar info and amp settings.

Not enough such for Tweed Deluxe/5E3's on the Web.

Have you tried jumpering the 2 channels yet?


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Fri May 06, 2011 11:51 am
Offline
Hobbyist
Hobbyist

Joined: Thu Mar 31, 2011 11:44 am
Posts: 67
Location: Houston, TX
Looks glorious! Can't wait to hear your feedback of the moded vs the stock Tubedepot build.

_________________
"If it ain't one thing, it's another."


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Fri May 06, 2011 7:07 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Sat Mar 20, 2010 2:30 pm
Posts: 792
Location: A Land Downunder
Thanks for the feedback Arjay - much appreciated. 8)

jbloggs - I have jumpered the channels on these amps and it does deliver up some new sounds, actually the volume controls are quite interactive even without jumpering and there is a world of knob twiddling to get lost in, even with just the three knobs to play with! 8)

I'm firing the amp up and testing voltages etc, today and will be running it tonight at a rehearsal to give it some burn-in time. From there on I'm in two minds about whether to hang onto it and take them both to gigs (pretty easy to lug 2 of these little buggers :) ) using one as the main rig, with the other as a backup spare if ever needed, or find a new home for this brand-new one and indulge myself by redirecting the proceeds into another build, or even that Vintage '62 Hot Rod Strat I've been coveting :?:

Tough decision, seems like pure indulgence any away I go fom here!!! :mrgreen:

Matt I will report back with a comparison, I will try to get something recorded, I'm just not up to speed with this You-Tube thingo at the moment!! :lol:


Snowy


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Sat May 07, 2011 5:31 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Sat Mar 20, 2010 2:30 pm
Posts: 792
Location: A Land Downunder
Well, the results are in, the amp came to life fine, no problems to troubleshoot which is just how I like it!


I did some checking of the voltages and I also like checking where the tubes end up biasing just to be safe and I decided to drop the B+ voltage to about 360 volts and this got the plate dissipation right in the ballpark for a 5e3. I did this with some 15 Volt/5 watt Zener diodes between the Power Transformer Centre tap and Ground.

So for those interested and future reference, here's how the calculations came up on my amp and if you decide to build your own you can use this method with your own numbers to check things out:

I measured following to start with:
Voltage across Cathode Resistor = 21 volts
Actual Measured Resistance of Cathode Resistor = 250 Ohms
Plate Voltage (Pin3 to Ground) = 357 volts

Plate Current calculations:
Cathode Resistor Voltage (21 volts) / Cathode Resistor Ohms (250) = 0.084 (84 milliamps)
This is the Cathode Current (including screen current) for BOTH Tubes.
Subtract the screen current (measured to be 3.5ma) = 80.5ma
Divided by 2 (tubes) = 40.25ma Plate Current per tube

Idle Dissipation calculations:
Plate Voltage (357 volts) - Cathode Resistor Voltage (21 volts) = 336 volts
multiplied by Plate Current (.04025ma) = 13.5 watts

Pretty good, a bit on the warm side but for a Cathode biased 5e3 perfectly acceptable and it sounds great!! 8)

I ran both amps at a rehearsal last night and there is a difference between the two amps, the new build is noticeably brighter than my previous 5e3 build. This is apparently expected with the Orange Drop tone caps, but the speaker is also brand-new compared to the other amp with quite a lot of hours on it now. So I'm thinking as the speaker breaks-in the difference will minimise and while each amp will retain it's character, ie one brighter and one warmer, I don't expect they will be chalk and cheese, I think the final difference will be minimal after full speaker break-in.

Snowy


Last edited by No457 Snowy on Mon May 09, 2011 3:30 pm, edited 1 time in total.

Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Sun May 08, 2011 5:45 am
Offline
Professional Musician
Professional Musician
User avatar

Joined: Sun Feb 15, 2009 3:52 pm
Posts: 2005
Snowy,
Thank you for how you calculate this stuff! Wonderful info that I need to keep safe somewhere for future reference.

Again, outstanding work on the build(s)! Wish I could hear them in person.

Hope to ask you in a few months how they both compare.

_________________
-T

"You can't spend what you ain't got, you can't lose what you ain't never had" ~ McKinley Morganfield


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Sun May 08, 2011 3:14 pm
Offline
Hobbyist
Hobbyist

Joined: Sun May 08, 2011 2:40 pm
Posts: 14
Location: Round Rock, Texas
Snowy,

I've been following your builds closely. In fact, I'm halfway through building a Tube Depot 5e3, inspired largely by your build diaries.

May I ask two questions?

  • - Did you trim the output transformer secondaries for easier routing before attaching them to the speaker output jacks? I seem to have a great deal of extra wire there, much more than I see in your pictures.
  • - How does using the dim bulb tester fit in with the initial start-up tests outlined in section 8 of the build manual? I don't know the most appropriate order for moving through the manual's test sequence and the 15W bulb to 100W bulb sequence with the dim bulb tester.

Thank you very much for sharing your experience with us. It's made a huge difference in my confidence level in tackling this project.

Ross

_________________
Sinistershade
Round Rock, Texas
5e3 Build Pics


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Sun May 08, 2011 3:53 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Sun Feb 15, 2009 3:52 pm
Posts: 2005
sinistershade wrote:
Snowy,

I've been following your builds closely. In fact, I'm halfway through building a Tube Depot 5e3, inspired largely by your build diaries.

May I ask two questions?

  • - Did you trim the output transformer secondaries for easier routing before attaching them to the speaker output jacks? I seem to have a great deal of extra wire there, much more than I see in your pictures.
  • - How does using the dim bulb tester fit in with the initial start-up tests outlined in section 8 of the build manual? I don't know the most appropriate order for moving through the manual's test sequence and the 15W bulb to 100W bulb sequence with the dim bulb tester.

Thank you very much for sharing your experience with us. It's made a huge difference in my confidence level in tackling this project.

Ross



Ross, you should post these pics in another build topic!
I just went through them and they look good!
How did you apply the shellac?

_________________
-T

"You can't spend what you ain't got, you can't lose what you ain't never had" ~ McKinley Morganfield


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Sun May 08, 2011 4:28 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Sat Mar 20, 2010 2:30 pm
Posts: 792
Location: A Land Downunder
sinistershade wrote:
Snowy,

I've been following your builds closely. In fact, I'm halfway through building a Tube Depot 5e3, inspired largely by your build diaries.

May I ask two questions?

  • - Did you trim the output transformer secondaries for easier routing before attaching them to the speaker output jacks? I seem to have a great deal of extra wire there, much more than I see in your pictures.
  • - How does using the dim bulb tester fit in with the initial start-up tests outlined in section 8 of the build manual? I don't know the most appropriate order for moving through the manual's test sequence and the 15W bulb to 100W bulb sequence with the dim bulb tester.

Thank you very much for sharing your experience with us. It's made a huge difference in my confidence level in tackling this project.

Ross


Hi Ross, Welcome to the forum!

Great to hear you are tackling a build, Pretty exciting isn't it? 8)

Your pics look great too, I find documenting with pics and a diary kind of helps you get right into the project and naturally slows you down to reflect on the build and gives you more chance of catching any issues.

Yes, I did trim the OT leads to the required length, I found that having all the leads in the build to a "comfortable" length is the best way to go not only for neatness but also to reduce the chance of generating any hard to trace noise issues.

With the dim-bulb tester, use it right at the first power up step in the start-up steps.
You should use several different wattages of bulbs. I usually start with
15W ... then if all is safe, I move up
to 25W .... then 40W ... 60W ... 100W. If there are no arcs and sparks or
smoke on any of the in between bulbs, by the time I get to the 100W bulb, I
feel comfortable that the power section is not shorted. At this point, I then plug the amp straight to the wall as normal and start taking measurements in the amp and comparing them against stated
"standard" values in the manual.

So once you've got it running straight off the wall without issue, you can move onto the step of installing the Rectifier tube, and performing the startup testing as per the manual.

The purpose of the dim bulb tester is to allow only limited current through
the amp, similar to how a variac works. The smaller wattage bulbs have a
higher internal resistance which constricts the flow of current. The larger
the wattage, the lower this internal resistance and therefore the more
current that is allowed to flow in the amp. By starting with the low
wattage bulbs, you start the test with minimum current flowing through the
amp. If there is a wiring problem, the potential damage is greatly
contained. Gradually move to more and more current flow (higher wattage
bulbs) until there are no bulbs and you are running straight from the mains.

Hope that helps out.

Snowy


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Sun May 08, 2011 5:54 pm
Offline
Hobbyist
Hobbyist

Joined: Sun May 08, 2011 2:40 pm
Posts: 14
Location: Round Rock, Texas
Quote:
Ross, you should post these pics in another build topic!
I just went through them and they look good!
How did you apply the shellac?

_________________
-T


Thanks, Tyronne, but I can't compete with Snowy on build or picture quality. :-)

Finishing the cabinet has been the real Waterloo of this build (which is my first). Wanting to maintain the vintage vibe, I chose to go the clear shellac/amber shellac/nitro lacquer route. Truly, I should never pick up a paintbrush.

The clear shellac was pretty much a breeze. The Zinsser clear shellac in rattle cans was very easy to work with. Three coats and done.

The Zinsser amber shellac, however, doesn't come in cans, and all the references online to using it on tweed suggested cutting it 1:1 with denatured alcohol. Getting it even was beyond me. I did a lot of wet sanding and reshellacking. At one point I ended up with a patch on the top of the cab that had reverted to almost bare tweed and wouldn't take any color. Leaving it to dry allowed me to shellac the patch, but I could never get the edges clean. Finally, I masked off the entire top, stripped it with alcohol, and started over. Ultimately, I got it to a point I can live with, but it's darker and more orange than I'd intended, and there are a variety of imperfections that will mock me as long as I own the amp.

But it's supposed to look like it's spent 50 years in smoky bars having drinks spilled on it, right? :-)

The nitro lacquer was also very straightforward. DEFT satin wood lacquer in rattle cans. Ten coats applied over a seven-hour period, and I was done. The cabinet is now hanging in my garage for a week of curing for the lacquer.

If I ever do another one of these, I'll either forgo the shellac altogether and just lacquer (in the manner of the Fender original) or spring for spraying gear for the amber. Or, heck, just give in to modernity and use a Minwax product.

Ross

_________________
Sinistershade
Round Rock, Texas
5e3 Build Pics


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Sun May 08, 2011 6:15 pm
Offline
Hobbyist
Hobbyist

Joined: Sun May 08, 2011 2:40 pm
Posts: 14
Location: Round Rock, Texas
Quote:
. . .

Your pics look great too, I find documenting with pics and a diary kind of helps you get right into the project and naturally slows you down to reflect on the build and gives you more chance of catching any issues.

Yes, I did trim the OT leads to the required length, I found that having all the leads in the build to a "comfortable" length is the best way to go not only for neatness but also to reduce the chance of generating any hard to trace noise issues.

With the dim-bulb tester, use it right at the first power up step in the start-up steps.
You should use several different wattages of bulbs. I usually start with
15W ... then if all is safe, I move up
to 25W .... then 40W ... 60W ... 100W. If there are no arcs and sparks or
smoke on any of the in between bulbs, by the time I get to the 100W bulb, I
feel comfortable that the power section is not shorted. At this point, I then plug the amp straight to the wall as normal and start taking measurements in the amp and comparing them against stated
"standard" values in the manual.

So once you've got it running straight off the wall without issue, you can move onto the step of installing the Rectifier tube, and performing the startup testing as per the manual.

. . .

Hope that helps out.

Snowy


Thanks, Snowy. For me, this build has been an exercise in patience as much as anything else. I'm trying to go slow and do it right, which is not my nature. Taking pics helps, and they've also allowed my two guitar-playing brothers who live far away to join in vicariously.

Thanks for your insights. I figured trimming the OT leads was the way to go, but it's nice to have it confirmed. On the dim bulb tester, I understand you to suggest doing the ever-increasing bulb-wattage routine before the testing detailed in the manual and doing the dim-bulb routine without the tubes or the speaker-load in the circuit. I also seem to recall something about letting the amp run for a couple of hours at each bulb level to "form" the capacitors. I'll have to look into that more.

I think I'll use the dim bulb tester design detailed on this site, though being intended for vintage radio work, it doesn't include a ground connection. I'll have to figure out how to add that.

For anyone looking at my pics, I should offer a disclaimer that I varied from the standard Tube Depot kit in three respects. I upgraded the filter caps to F&Ts, the coupling caps to Mallory 150s, and power tube cathode resistor to the Ohmite Brown Devil. These upgrades are available from Tube Depot at the time of ordering (just specify them in the "Comments" field) and added only about $16 to the price.

Ross

_________________
Sinistershade
Round Rock, Texas
5e3 Build Pics


Top
Profile
Post subject: Re: Let's build another Tweed Deluxe Amp!
Posted: Sun May 08, 2011 7:13 pm
Offline
Aspiring Musician
Aspiring Musician
User avatar

Joined: Sat Mar 20, 2010 2:30 pm
Posts: 792
Location: A Land Downunder
Hi Ross,

You don't have to run each bulb for a couple of hours, I just use each bulb for for 30 seconds or so to confirm all is OK (no smoke, burning smells, popped fuse, etc - if it is not OK you will find out very quickly!! :shock: If there is a short, the bulb will turn much brighter as more current is drawn) If it is ok after 30 seconds or so, then turn off at the wall and install the next bulb and switch on again and observe for 30 seconds etc. If something is wrong turn the power off at the wall switch, don't touch the switch on the amp itself. During all the testing just leave the amp's standby and power switch on and use the wall switch/pull the plug to connect/disconnect the power.

Initially I usually plug a standard multi-plug Power Strip (the type that has an integrated circuit breaker) into the wall just for an added layer of protection, then run the dim bulb tester from that and then the amp from the bulb tester. Once the bulb sequence is done I'll plug the amp straight into the Power Strip -> Wall Outlet.

Take your time and triple check everything you do while building, it's the easiest time to spot a mistake, where possible use your digital volt meter's Continuity function to check your connections as you solder them, once you have a finished amp it becomes harder to spot and fix something.


Cheers,

Snowy


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 137 posts ]  Go to page Previous  1 ... 4, 5, 6, 7, 8, 9, 10  Next
Go to page Previous  1 ... 4, 5, 6, 7, 8, 9, 10  Next

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: 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

Search for:
Jump to: