The Amp Garage

Does the PI have to change for a 100W? Fender circuits seemed to favour 12AT7 and a change in the cathode resistor of the PI for four output tubes (although I've seen the standard 12AX7 PI in earlier circuits). There was a great thread on the BluesMaster and PI changes, but it didn't touch on the di...

Thanks alot for this effort Mark. Well done! But....I can not tell a lie. Dogears pointed out the criss-crossed PI resistors. So...much thanks to him for this and so many other outstanding pointers and suggestions. Dave O. Well then, thanks for sharing it with all of us that might've stumbled into ...

I swapped the 82k and 100k plate resistors on the PI.
Thanks to AmpGeek on the Brown-Note Forum for catching this!

Ok folks, I'm putting together my chassis order and i wanted to know how many of you are truly going to want one. Do any previous customers have suggestions? Hi Funk, I want a complete set, with PCBs... hopefully the weight is light and the postal shipping to Canada won't be ugly $$$. My only sugge...

In my first tries the built in microphones seem to clip/distort while close-mic'ing the amplifier. What mics were you using?[/quote] My first experiments were with the built in mics... been playing with dry clips (Guitar recorded DI to the H4, phones out to amplifier for feedback/dynamics)... then ...

I just got one of those Zoom H4 Handy Recorders. It's definitely one of those "how did I survive without it???" items for me. So, here's a wacky Express clip, no movie necessary! http://www.theinside.net/Expressclip2.MP3 I think those EL34's are about done, though.... :( What is your setup for reco...

Mark, can you give me some numbers for your voltages? Where did they start and how close did you end up getting them to the numbers on the scheme? Mine are all a bit high, but I figured they were acceptable. The wall voltage at my house is about 124V+ AC, and the B+1 ends up being about 415V DC wit...

Well, I don't have a guts picture right now and that's probably a good thing! It's a little messy right now because I've been doing a lot of experimentation with the components. Certainly lead dress could be my issue, but before I made all the experimental changes, the layout was similar to Frances...

OK, fellas, I just finished prepping the chassis. I know I've got a busy day for myself tomorrow mounting components, filament wiring, etc., but I already have questions regarding bias, so here goes: 1) Looking at version A1 I see that the bias pot is rated for 20k. All I have is a 10k bias pot. Ar...

I just finished an Express clone with Ceriatone chassis/board and Moose transformers. Using EL34s I can bias the amp fine. I use 70% of max power dissipation method for the tube by measuring current at the cathode. But, using a 6V6 I can only set the minimum power dissipation to 12W, which I think ...

I think you suggestion of a 'reference' set of clips is a dandy idea! I have some thoughts on this... maybe fodder for a separate thread? To the rest.. Is it sounding dumble-esque or should I just stick to my day job? 100+ downloads and one critique? Come on guys! I'm dying here! :( Maybe we could ...

Who is this Scott Lerner guy?? And why does Dogears seem so familiar??? I wonder is Dogears could attempt Giant Steps as you have!!! I bet not 8) PS: I need to check this out on my home system to critique. These work speakers are lame! Good playing btw. Yep - I guess I should have mentioned that Gi...

Have you considered having the AC in and DC rectification/filtering for the relay supply on the same end as the HT supply? Then you can use the 5V winding on the transformer (if it has one) like the D'Lite Relays version without a long run of AC twisted pair to the other side of the amp.

ampdoc pointed out a few mistakes which I corrected. Turns out I had a pot designation wrong so middle and bass were reversed. Also, this is not exactly a D-Lite schematic, it's an HRM schematic that I've used before successfully, I only called it a D-Lite because that seems to be the de-facto stan...

You might get more 'takers' if you print the output of the pcb software to PDF format and post that. Then everyone can look at it without having to install that software. (In an effort to keep things tidy, took it off my PC and I'm loath to re-install it again!!) ;-) Not everybody has the ability t...