100W Bluesmaster is Born

[martin manning]

Input-side Plate, Pin 6: 270V
Feeback-side Plate, Pin 1: 242V
Is there a typo here?

It’s possible I recorded the voltage incorrectly when taking notes. With a balanced tube and the PI trimmer set halfway, I’d expect them to be roughly 250V per side. I dunno…

Maybe it's 250 and 242 then... Was that about the time when Billy got poked? ;^)

I also apreciate the detailed specs and pictures; thanks for posting them!

MPM

[Structo]

Yes I would have figured with the trimmer there that you would have the voltages closer together.
Perhaps if you tried a few different tubes there you could get the preferred voltage spread.

[UltraHookedOnPhonix]

Kind of a stupid basic question, but what are the blue capacitors on your power board? The ones I got from Mouser were smaller in diameter and green (47uf/250v).

Mouser part#: 140-XRL250V47-RC

The HRM board can be supported by taller nylon or plastic stands isn't that what one should do?

Should do? I think it’s something one could do. All Dumble HRM guts I’ve seen are supporting the board with RTV and I wanted to follow that theme since it is a Dumble I’m trying to build. Whatever floats your boat IMHO.

Are you planning to make some PCB's for it?

I’m not sure if this question is directed at me but no. These boards were drawn by hand which was a major pain but an authentic look was important to me. Here’s a pic of all the PCB traces used for the build before they were etched:

[IMG:819:1023]http://i205.photobucket.com/albums/bb17 ... tching.jpg[/img]

Input-side Plate, Pin 6: 270V
Feeback-side Plate, Pin 1: 242V
Is there a typo here?

It’s possible I recorded the voltage incorrectly when taking notes. With a balanced tube and the PI trimmer set halfway, I’d expect them to be roughly 250V per side. I dunno…

Maybe it's 250 and 242 then... Was that about the time when Billy got poked? ;^)

I also apreciate the detailed specs and pictures; thanks for posting them!

MPM

I just noticed this but scribbled on my paper is also the voltage before the plate resistors (outside lugs of the trimmer) which read: 405V and 407V. So yes, the 270V must be wrong.

[tubedogsmith]

Awesome looking build!! As nice as I've seen, the attention to detail is cool!! How are you diggin' the tones?

[UltraHookedOnPhonix]

Awesome looking build!! As nice as I've seen, the attention to detail is cool!! How are you diggin' the tones?

I'm left without a speaker cab for a brief moment (approx. a week) so, my only tonal reference is from what Billy managed to squeeze out of it. I can imagine it'll take a while before I get used to the separate masters since I've been playing a non-HRM for a while but as far as the sound is concerned, this amp is a whole-lot more Marshally for sure. It's like a really really fat old Marshall but with a smoother edge. Just what I was hoping for! I was really surpised when Billy told me the cab he was playing through had an EV12L in it because I would have expected it to be much brighter, maybe even on the shrill side but it sounded very balanced. I can't wait to crank this thing up next week-end!
Thanks again tubedogsmith!

[Structo]

I have a 2 x 12 with EVM 12L's.

I don't really notice a lot of high end although they are capable of it but
certainly shrill is not a word I would use to describe them.
What I really notice is the ability to handle bass and clarity.
I can imagine in a closed back or 806 cab they are really punchy.

They have a lot of clarity and don't hide what the amp is doing.
But they will reveal any abnormalities or crappy tones so there is no hiding behind a speaker with these.

They let the amp be heard for what it is, good or bad.

I have even played bass guitar through mine with no problems and it actually sounded pretty darn good.

[UltraHookedOnPhonix]

I have a 2 x 12 with EVM 12L's.

I do to: http://losangeles.craigslist.org/wst/ms ... 82335.html

They have a lot of clarity and don't hide what the amp is doing.

I like to challenge this statement which shows up regularly when discussing the EVM12L. So, what happens when you turn down the treble control on your amp? Aren’t you also then hiding what the amp is doing?

They let the amp be heard for what it is, good or bad.

Question: can you have a good amp that sounds bad with an EVM12L? Since the speaker is the last component in the signal chain, I suppose it’s tempting to label it: judge, jury and executioner.

I have even played bass guitar through mine with no problems and it actually sounded pretty darn good.

I think EVM12L speakers sound great too…sometimes. With Billy’s cab, it sounded awesome!

[tubedogsmith]

What's connected to the wire loop on the HRM board? Is there room under those pots to get a lead in to measure them?

[ukulele]

Great looking build, maybe the best I've ever seen.
Please post some clips too!

Just one question, where did you get that solid core cable.

Thanks, Mikael

[UltraHookedOnPhonix]

What's connected to the wire loop on the HRM board? Is there room under those pots to get a lead in to measure them?

It's there for show. It's a sham I tells ya'!
Quite frankly, I don't know what the function of that test point is anyways. So, it's only there to look the part. There are reports that it connects to a capacitor, which leads to the plate of V2B/OD2 but I don't know what that would enable.

There's no room under those pots.

Here's how the board looked before I secured it with RTV:

[IMG768]http://i205.photobucket.com/albums/bb17 ... reGoop.jpg[/img]

[ChrisM]

O rocking a few 715P caps in there. Are those in the PI? I understand the PI isnt picky about caps.

[Structo]

Well Hooked,
That looks like a good cab you are getting. Has the required Dumble oval rear port.

Just like everything that audible by human beings, speakers are also subjectively rated.

No two people hear the same thing depending on how discriminatory or selective their hearing is.
And as we all know, the enclosure influences the way the speaker behaves and sounds as well.

Guitar amps, pickups, tubes, speakers, etc. are all rated by subjective opinions.

I can say this about the EVM's, they are the best speaker I have used.
I have a crappy Lopoline 2 x 12 cab right now for the EVM's.
I can't wait until I get a much better cab to hear them in.

BTW, I think I remember a member saying that hook of wire on the HRM board was a test point.
A test point for what, I do not know.

[jelle]

Another factor is that not all EVM's are alike. There is the Series I and II for instance. Those have different sounds.


jelle

[talbany]

The 300 watters to me don't sound nearly as good as the 200's ..

Tony

[UltraHookedOnPhonix]

Well Hooked,
That looks like a good cab you are getting. Has the required Dumble oval rear port.

Just like everything that audible by human beings, speakers are also subjectively rated.

No two people hear the same thing depending on how discriminatory or selective their hearing is.
And as we all know, the enclosure influences the way the speaker behaves and sounds as well.

Guitar amps, pickups, tubes, speakers, etc. are all rated by subjective opinions.

I can say this about the EVM's, they are the best speaker I have used.
I have a crappy Lopoline 2 x 12 cab right now for the EVM's.
I can't wait until I get a much better cab to hear them in.

BTW, I think I remember a member saying that hook of wire on the HRM board was a test point.
A test point for what, I do not know.

Actually, that's the one I'm selling!

You're absolutely right about it being subjective. It's a bit like trying to explain to someone why yellow is a better color than red.