Tweed Champ Clone

About seven years ago, I had the desire to build something.  I settled on a guitar amplifier.  I ended up buying a tweed Champ kit from Marsh Amplification.

When I purchased the amp, I opted for a smooth cone Signature series 8" Weber speaker as an option over the ceramic speaker.  I was also sent a lacquered cabinet.

The quality of the kit was great.  I had some problems that could be chalked up to it being my first build.  Once I got it straightened out, it has worked flawlessly.

After playing with the amp for a couple of years and loaning it out for a few recording 

sessions, the original speaker died.  

I really liked the sound of the smooth cone Weber in the amp.  After reading an evaluation of 8" speakers in harp amps written by Brian Purdy of Harpgear amps, I decided that I was going to pick up a smooth cone Vintage series Weber speaker.  I settled on the 8A125-O speaker with a H dust cap.

Compare the two speakers, the original Signature series on the left, the Vintage series on the right. 

How does it sound?  

Pre-WW2 Valco-made Amp

It's been a while, since I've had the chance to write here.  I thought I would write up an entry about an old Valco amp with a Tower label.  I was given this amp in exchange for some web development about a fifteen years ago.  Here are a couple of photos of the amp.

Since, it appeared original, I decided that it should probably be looked at.  I took it to Skip Simmons Amp Repair in Dixon, CA.  He checked it out and touched up some solder joints and pronounced it good to go.  When I asked Skip about it, he said that it was likely made by Valco, but he had never seen one before.


A few years later, I was curious about the amp.  After doing some research on the Internet, I couldn't find any information about the amp.  I posted some questions on the Valco Amp site.  I received no response.  At this point, I was content knowing that it was a Valco-made mystery amp.


A while ago, I was considering trading it when I received an e-mail from Terry Dobbs (a.k.a. Mr Valco):

"This amp is the same circuit as the first Valco made Supreme amps, however, it was made before WW2 by the same company that made the National Dobro amps, in other words, before Valco was Valco. It has a 10" 4 ohm field coil speaker, 5y3, 2-6V6's, 6sc7 and a 6J7. Single volume and no tone control and two inputs. It is a nice little amp and they sound great when serviced and working right."

Okay, enough talk...  How does it sound?  Let's take a listen...

What do you think?

Astatic JT-30 Demo

In the spirit of my last couple of entries, I thought I would break out some microphones.  This time, I grabbed a brand new Astatic JT30 Roadhouse, a Hohner Blues Blaster with a MC-151 element and a Hohner Blues Blaster with a Shure Controlled Magnetic Element.  I plugged them into a Super Sonny amplifier.  I set up a Zoom H2 recorder about ten feet away from the amp and played a bit. 

1. Microphone 1
2. Microphone 2
3. Microphone 3

Which mic is which?

Shure Green Bullet Demo - Round Two - Answers

Here are the answer from the blind audio test of the Shure Green Bullet microphones.

1. 520D
2. 520DX
3. CM in Blues Blaster
4. CM in JT30

Did you get them right?  Could you live with any of them?

Shure Green Bullet Demo - Round Two

Some of the feedback that I received on the previous installment was quite interesting including: 

"It would be better if you didn't announce what mic you were playing and obscured them so bias couldn't enter in.

"If you hadn't said which was which I don't think many players could tell the difference."

"Joe is playing through a Tweed Champ clone. Like other small amps it adds a lot of its own breakup and color, which tends to make mics sound more alike...  Played through a bigger amp you will hear the differences more." 

"However to create a test to get people to choose which mic they think sounds best, or indeed to identify a particular element. The only real way to do that is to perform a blind test."

I decided to heed the advice that I was given.  

1. The second round is audio only.  That way, no one could see the microphones.  (You'll have to trust my honesty and integrity.)  
2. In this round, I used a Super Sonny.  It's a bigger amp.  There were no changes to the volume or tone settings when I changed microphones.
3. I set up a Zoom H2 about 15 feet away from the amp.
4. I tried to play the same thing each time and the same thing from the first test.

On with the fun.  The microphones being tested are a:

• Shure Controlled Magnetic (99A86) in a vintage JT-30 shell.
• Shure Controlled Magnetic (99A86) in a Hohner Blues Blaster shell.
• Shure 520D with a Mexican made element.
• Shure 520DX with the modern dynamic element.

Clip of Microphone #1

Clip of Microphone #2

Clip of Microphone #3

Clip of Microphone #4

What do you think?  Which microphone is which? 

Shure Green Bullet Demo

A while back, I was reading an Internet forum about the merits of a variety of microphones commonly used by harmonica players.  The microphone in question was the Shure Green Bullet.  Since, I had several of these microphones, I decided to pull out a few of them do some back to back testing.  I decided to run the various micrphones through my tweed Champ clone to eliminate tweaking of an amplifier's tone controls.

For this test, I plugged the microphone directly into the amplifier.  I set the volume control on the amp at six.  I ran the following microphones through the test:

1. A Shure controlled magnetic element (99A86) in a JT30 shell.
2. A Mexican-made Shure controlled magnetic element in a 520D shell
3. A modern dynamic Shure element in a 520DX shell.

Tweed Champ Clone Demo

Back in 2006, I was going through a period in my life where I felt the need to create something.  Normally, I would have build a computer.  I really didn't need another computer.  I decided to build an amplifier.  After a bit of researching amplifier kits to death, I decided to build a clone of a tweed Fender Champ from Marsh Amplification.  It was a fun process.  After playing it quite a bit, I ended up blowing the speaker.  I replaced it with a Vintage Series Weber speaker, 8A-125-O.

A while ago, I ran across a video that I shot in 2006.  It didn't really represent the amp well, so I decided to set up a video camera and play a bit.  Here is the result with a vintage JT-30 microphone and a plaid flannel shirt.  I'm not sure that it's any better than the original video, but here it is:



Here is another video with a modern Shure 520DX with the original modern dynamic element.  This microphone is generally regarded as a complete turd among harmonica players.  It didn't seem so bad in this video.  More importantly, I was wearing a black T-shirt: