The Amp Garage

Hey All, I just picked up a '66 Bassman. I opened it up to look at the circuit and found that the bias had already been changed over, so far so good. Then I started looking into the feedback loop. This has been modified as well. There is the 820 Ohm resistor except it is not connected to the OT it i...

To All, I didn't post internal shots 'cause they are the same as we've all seen before and she's all buttoned up now. The name under SierraTone is "Bridgette". I thought I'd do my amps alphabetically. My first was a AC30 / Marshall take which I named "Angelina". My wife asked why I didn't name one a...

To All, After nearly 6 months of building and another 9 months of tweaking / gigging. I think I'm going to close 'er up for a while and enjoy what I have. I used Brandons chassis and boards, Fender Iron and have pretty much stuck to the ODS-HRM-101 schematic. Many thanks to Brandon for his patience ...

Hey All, Thanks for the replies. I did look closely at the relay. I had butchered the board pretty bad and thought that there may be the problem. As it turns out, I think I had a bad preamp tube. I moving things around and tapping inside, I noticed that V1 seem kinda microphonic so I swap some other...

To All,

I've noticed that I have more than acceptable level of hum in the ODS/HRM channel. If I switch to the clean channel, it goes away. All volume controls seem to effect the hum as does the entrance trimmer. I've tried moving wires around with little effect? Any suggestions?

Cheers, Mike

Hey All,

There is a lot of talk on in the forum about the Dumbleator and Kleinulator. Question is.... Don't modern effects really buffer the signal themselves? I don't hear much unwanted signal change when I use a couple of effect in series in this loop.

Cheers, Mike

Hey All, I would like to be able to kick up the volume level of a #124 style amp via a pot and on/off switch. I other words... I would like a 'solo' control to boost the loudness whether the amp in is the normal or OD mode. I'm thinking that I would like a pot to set the level and then a relay and e...

I used 30pF across the MV.

Best Regards, Mike

The treble cap is .002 uF with a 390 pf 'Bright cap'.

The OD drive is a 100k pot with a 150k resistor.

All pretty much exactly like the #124 schematic.

Thanks!

Hey All, I had finished by build based on #124 a few months ago. A have loaned it out on a number of occasions to fellow players to get there feedback. To a man, they have all said it needs for highs. One guy with a Tele said it was O.K. for him but all the others, using a strat, 335, and a Les Paul...

O.K. - this is just a what if....

I've built a 100W ODS-HRM with a blues Master PI. I am wondering what the groups suggestion would be on voicing this for a bass. I am also thinking what I would get if I went to KT88's rather than 6L6's.

Cheers, Mike

Hey All,

I have a '90's era Fender Bassman 60 that a friend gave me to repair. The volue pot is broken on this. This is a PC board pot with a shaft that extends through the front panel.

Does anyone know how I can find the part number and where to buy a replacement?

Cheers, Mike

Just a thought....

With the tone controls all the way off, you will have no volume. If you begine to turn the bass, mid or trebll control up just a little it will suddenly come on.

Cheers, Mike

Hey All,

I'm thinking that I'll use 18 AWG on the power tubes followed by 20 AWG on the Pre-Amps'... 600V of course.

Trying to get 18 gauge into those tiny 9 pin sockets is about the limit of my skill!

Cheers, Mike

Instead of, or in addition to, the standard PAB arrangement you could "lift" the bass and Mid pots (disconnecting them from ground). This gives you a lot more gain. I've seen this as an alternate version of the PAB, where the relay lifts the Bass and Mid grounds. Might try this. The resistor on the...