Hey guys need your help I have a little Dot MK 2 headphone /preamp. What I want to do is I'm going to take it out and put it in a different case I don't like the chassis that it's in.
Since I'm taking it apart what I want to know is based on the photo are there any audio upgrades I could do to this film capacitors coupling capacitors something like that you guys think would make a sonic difference in the amp?
Since I'm taking it apart what I want to know is based on the photo are there any audio upgrades I could do to this film capacitors coupling capacitors something like that you guys think would make a sonic difference in the amp?
Attachments
A sonic difference?
Please be specific.
More high frequencies;
Less distortion;
More Bass;
Accentuated midrange;
More power output;
Part of getting a good answer depends on what the performance of that amplifier is before you modify it.
What do you like about it?
What do you dislike about it?
Perhaps it is as good as it gets.
Please be specific.
More high frequencies;
Less distortion;
More Bass;
Accentuated midrange;
More power output;
Part of getting a good answer depends on what the performance of that amplifier is before you modify it.
What do you like about it?
What do you dislike about it?
Perhaps it is as good as it gets.
If you are starting with a new chassis why not rebuild the amp point to point, and get another amp out of the deal? You are going to have to solve the issues of cutting holes for the tube sockets in just the right places, so buying some chassis mounted sockets, and putting the holes where you want them saves all that hassle. Then you just need to think about the layout underneath before making holes.
What does the new chassis look like?
What does the new chassis look like?
Well, i don't have a lot of experience, i have recapped a few stereos is about it, and i know how to solder of course, never done any point-to-point. I know there is an advantage to point, but would know where to even begin to do it, i like to though.
The new chassis is going to be a wood box made of cherry wood with a black metal top for the tubes and transformer to sit on, something like a bottlehead crack look but not exactly. I want the inputs and outputs to still come out the back, not on top. The volume and headphone jack to be in front may add a metal front with the 2 sides and back cherry wood. I'm still tossing ideas around. I want to see first what i can do to upgrade the sound quality if that is possible.
Accentuated midrange;
I know tube rolling will help for sure, but since im going to take the amp apart and put it in a totally different chasis i thought why not upgrade the internals. It maybe as good as it gets, i guess you wont know that unless you try right ?
The new chassis is going to be a wood box made of cherry wood with a black metal top for the tubes and transformer to sit on, something like a bottlehead crack look but not exactly. I want the inputs and outputs to still come out the back, not on top. The volume and headphone jack to be in front may add a metal front with the 2 sides and back cherry wood. I'm still tossing ideas around. I want to see first what i can do to upgrade the sound quality if that is possible.
More bass,
Accentuated midrange;
I know tube rolling will help for sure, but since im going to take the amp apart and put it in a totally different chasis i thought why not upgrade the internals. It maybe as good as it gets, i guess you wont know that unless you try right ?
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Isn't the one in there 10k? If so, I would definitely not change the value.
The schematic I've seen has the 10k pot included as part of the nfb loop.
A 100k pot would not work right in that circuit.
What other modifications are in the amp already (that someone before you put in)?
That takes some effort to check.
Get the amplifier working properly, and to original specifications; before you modify.
Or else you will never know what state it is really in.
An accurate and complete schematic would be very helpful.
More bass, could be circuitry, output transformers, negative feedback loop parameters, etc.
More midrange, as in the highs are over accentuated?
Or what?
Tube rolling?
As in different manufacturers of the same tube number?
As in using a similar tube type of a different number?
How much of the sound is due to the amplifier, and how much is due to the headphones?
Tailor the sound for a specific set of headphones; or for a more general change of sound for many headphone types?
What headphone types do you have?
That takes some effort to check.
Get the amplifier working properly, and to original specifications; before you modify.
Or else you will never know what state it is really in.
An accurate and complete schematic would be very helpful.
More bass, could be circuitry, output transformers, negative feedback loop parameters, etc.
More midrange, as in the highs are over accentuated?
Or what?
Tube rolling?
As in different manufacturers of the same tube number?
As in using a similar tube type of a different number?
How much of the sound is due to the amplifier, and how much is due to the headphones?
Tailor the sound for a specific set of headphones; or for a more general change of sound for many headphone types?
What headphone types do you have?
No mods have done that i can see, she sits all stock. I use this as a headphone amp/preamp, so 50/50 usage. No schematic is available, well only the headphone section, not the preamp section.
I think for me i want strong bass, tight bass, and well tubes are all about the midrange for the most part, that dreamy, midrange. I'm not saying it's bad right now, it's pretty good, but like all of u,s i want to squeeze the last drop out of it. How much do high-end parts matte? Mundorf cap, good capacitors, how many quality parts better the sound? i can't answer that. Im using HD 6XX headphones, i just changed the cheap tube that came with it for GE tubes and it was a big change, so tubes make a big difference for sure. I love my HD 6xx headphones, I'm just trying to get the max out of this amp. I think the $100 i paid for its use, is the best bang for the buck i have spent on audio, I want to use it as a preamp and also, have a vista spark audio II.
I think for me i want strong bass, tight bass, and well tubes are all about the midrange for the most part, that dreamy, midrange. I'm not saying it's bad right now, it's pretty good, but like all of u,s i want to squeeze the last drop out of it. How much do high-end parts matte? Mundorf cap, good capacitors, how many quality parts better the sound? i can't answer that. Im using HD 6XX headphones, i just changed the cheap tube that came with it for GE tubes and it was a big change, so tubes make a big difference for sure. I love my HD 6xx headphones, I'm just trying to get the max out of this amp. I think the $100 i paid for its use, is the best bang for the buck i have spent on audio, I want to use it as a preamp and also, have a vista spark audio II.
Bass:
How big are the output transformers?
How much primary inductance do they have?
What is the output tube type?
What is the output tube operating mode: pentode / beam power; Ultra Linear; Triode wired pentode / beam power; or Triode?
What is the plate current through the output transformer primary?
Changing output transformers might make the biggest difference on Bass; but that can be expensive, and there probably is not room for them.
at $100, that is great.
But I do not expect any real improvements for less than $100; perhaps much more than that.
Too many unknowns about the amplifier circuit topology, the output transformers, and any/all negative feedback, etc.
How big are the output transformers?
How much primary inductance do they have?
What is the output tube type?
What is the output tube operating mode: pentode / beam power; Ultra Linear; Triode wired pentode / beam power; or Triode?
What is the plate current through the output transformer primary?
Changing output transformers might make the biggest difference on Bass; but that can be expensive, and there probably is not room for them.
at $100, that is great.
But I do not expect any real improvements for less than $100; perhaps much more than that.
Too many unknowns about the amplifier circuit topology, the output transformers, and any/all negative feedback, etc.
https://www.bing.com/ck/a?!&&p=f7bf...WstaWktcmV2aWV3LW1pcmFjbGUtdHViZS1hbXAv&ntb=1
Output is 3 330uf 250b capacitors.................It has a weird output, better explained in link above. Im willing to dump $100 into it, new transformer no problem, remember im putting it into a new chassis, so the new transformer can work., yes, a lot of unknowns for sure.
Output is 3 330uf 250b capacitors.................It has a weird output, better explained in link above. Im willing to dump $100 into it, new transformer no problem, remember im putting it into a new chassis, so the new transformer can work., yes, a lot of unknowns for sure.
Attachments
Those are sitting in the power supply stage.
Not that they're not included in the output stage, last cap in the filter Always does.