Dogeaers compendium possible (untill today?)

[jazzcat]

Hi,

this forum is really full of information and full of the best in this subject but, for a newby like me, it will take weeks or more to understand , what is to change, to improve the sound.
Is it possible to make something like an overview to the expierience, you, Gil and all the others and marvellous Amp_Builders have collected in all the time.
This would make the orientation more easy and newbys will not repeat the same questions over and over.
Sorry, but i feel this way.
Dodears or anybody else , can you make something like Overview?

Thanks

[mcrracer]

Ruh Roh!

[Structo]

There was a thread of good mods and tweaks for ODS amps oh about a year ago or so.
But I'm afraid you will have to do the leg work on the search.

If you were to follow the #124 layout you would have a very good amp.

[Bob-I]

Hi,

this forum is really full of information and full of the best in this subject but, for a newby like me, it will take weeks or more to understand , what is to change, to improve the sound.
Is it possible to make something like an overview to the expierience, you, Gil and all the others and marvellous Amp_Builders have collected in all the time.
This would make the orientation more easy and newbys will not repeat the same questions over and over.
Sorry, but i feel this way.
Dodears or anybody else , can you make something like Overview?

Thanks

I don't mean to put you off, in fact welcome to the thing... but it really takes more than weeks to understand these amps, more like months or even years. There is no simple formula.

Like Tom said, study the #124 schematic as well as the ODS 101 and ODS 102 schematics.

[gilgalad101]

it really takes more than weeks to understand these amps, more like months or even years. There is no simple formula.

I second this. Though an overview may be a little more helpful, it's still going to take a lot of time for you to fully grasp the material here. I've been studying these forums for probably a year or so in addition to taking classes towards an EE degree at Clemson, and there are still plenty of things left for me to learn. I would recommend that you pick up a book or two about amps as a supplement to the forums. I'm currently reading the Radiotron Designer's Handbook, 4th Edition. Nice read, but it's a fairly lengthy book.

[jazzcat]

Sorry, but I use the search option really. But you are right. I have to enhance my background to understand the info better.
Thanks

[Structo]

In the Garage Talk section there is a list of books.

Not sure how well you can read English but there are some good books there.

Also don't know if they are available in Germany.

If you don't know anything about basic electronics I would recommend buying a book that a college (university) uses to teach basic electronics.

You first must understand how different components behave in a circuit before even getting into tube theory.
Things like Ohm's Law and Kirchhoff's Law, should be studied.
Otherwise you will be lost.

[gilgalad101]

Here are a few threads and links I've saved for myself that might be of help to you:

Large selection of books available for download -
http://www.tubebooks.org/technical_books_online.htm

Fine tuning and blueprinting guide -
https://tubeamparchive.com/viewtopic.php?t=4807

Changing resistors/caps guide -
https://tubeamparchive.com/viewtopic.php?p=51214

[jazzcat]

Thanks,
that helps me really.

I would not like to be impertinent, but btw.

I have a hrm 100 (like hrm 101 schematic) that sounds too hasch in the treble and the bass is not defined (muddy).
I tried different tubes but this does not resolve the Problem.
I have already wired a treble bleeder, and treble it's better but not good.
It seems like First Aid but not a cure (healing).
Bass is muddy like before, of course.
Mids sound a bit boxy (like a megaphone).
Do you have any idea to continue, a next step?
I search a Sound more close to 124 but not exactly 124.
I like the more open Sound of the HRM apart from that.
Anyway!
Thanks again!!

Dogears: Sorry for writing your nikname two times wrong.
This was not intended. (cosas que pasan)
I was tired an had to go to sleep.
Sorry again.

Jeron

[Sonny ReVerb]

I enjoyed this post by Henry:

https://tubeamparchive.com/viewtopic.php?t=6431

He made a valiant effort to kick off some discussion on tweaks for the various sections of these amps. Nobody picked up the ball, however.

[Structo]

Jazzcat what I have done is when I come to a post or thread with valid tweaking values or methods, I make a Word file document and copy and paste the content into the document so I have it for reference material later in time.

[Bob-I]

I have a hrm 100 (like hrm 101 schematic) that sounds too hasch in the treble and the bass is not defined (muddy).
I tried different tubes but this does not resolve the Problem.
I have already wired a treble bleeder, and treble it's better but not good.
It seems like First Aid but not a cure (healing).
Bass is muddy like before, of course.
Mids sound a bit boxy (like a megaphone).
Do you have any idea to continue, a next step?

It would help to get pictures and more details about the components used.

[Structo]

I have a hrm 100 (like hrm 101 schematic) that sounds too harsh in the treble and the bass is not defined (muddy).
I tried different tubes but this does not resolve the Problem.
I have already wired a treble bleeder, and treble it's better but not good.
It seems like First Aid but not a cure (healing).
Bass is muddy like before, of course.
Mids sound a bit boxy (like a megaphone).
Do you have any idea to continue, a next step?
I search a Sound more close to 124 but not exactly 124.
I like the more open Sound of the HRM apart from that.
Anyway!
Thanks again!!

Jeron

Jeron,

Is your amp home made or is it a Ceriatone?

What power transformer are you using?

If it is the ODS 101 HRM then compare the component values you have against the schematic.

Hopefully you know how to work inside an amp safely and take precautions against getting shocked or electrocuted.

A lot of guys use the ODS 101 schematics for reference.

I don't know anything about the HRM circuit so I can't really help you too much with the HRM part.

But I will say that most guys try to keep the voltages at a certain level.
I assume they apply to the HRM as well.

So you want V1 @ 190-195v, V2 @ 200-205v and V3 @ 295-300v.

You adjust those voltages by adjusting the dropping string resistor values on the power supply board.
These are the 3K, 15K and 10K resistors on the back edge of the power supply board.

Then depending what cap values you have on the main board you can adjust those and or the grid load resistors to cut or enhance highs.

So first thing is to get your voltages right.
Then if you still don't like it, ask about the component changes.

[jazzcat]

Thanks Tom and the others,
yes it is a Ceriatone build by Nik.
I have to check the voltages.
About your anxiety about the danger of the Voltage.. I can tell you that I am grounded.

I studied the schematics and understand more and more...
In some schematics, I saw every resistor and part labeled for examble: R1, R2 etc.
This is easier to understand..and speak about it.. isn't it?
Another thing is, that a schematic seems to be divided into different stages, like od entrance .. that you can not see in the schematic, without knowing the transition to the next stage. Is anywhere a basic overview?

The problem that I have now, is to compare the schematic of Hrm 101 with the layout on the Ceriatone page.
It's the next step to understand. What is different.

Live is for learning...learning is for existence.
Thanks :lol

[Structo]

Ah yes, you have a lot of reading to do my friend.

A stage in an amplifier is an active circuit that can amplify or change the level of signal in some way.

Take for example a 12AX7 tube.
It contains two triodes, that being the plate, grid and cathode.

It can be used as two stages in an amplifier.

The internet can answer just about any question you can think of.

I know that most scientific data is written in English so that may handicap you but if you persevere, you will learn all about tube amps.