Hello everybody,
Really new to this, just registed, and french, so sorry for my writting mistakes i do the same in french...
I started thinking about the amp of my dreams and realised that it doesn't exist !!
So, why not trying to make it myself !?!
I would have like a kind of VOX AC15HTVH1 head, but with the look of the Night Train ( for the box i can make it myself , that's not the probleme). With a spring reverb, like the AC30, no need of tremolo and vibrato, no real need of top boost, but i'd love to have a 2 mode switch on 1 jack; a EF86 mode with pentode-triode switch, and the bright levels like the AC15HTVH1, and an another mode with the classic bright channel from AC30, withe bass-tre-hig level and a kind of switch bright - thick like the night train so 2 x 12AX7 (one would be enough ?).
I'm a real pure novice but quite curious and trying to have a no-limite state of mind about what human can learn to do when we enjoy it !! And hopefully friends of mine are really good about DIY on ther electronic parts and have the good material and tools for it (optimist but not dumb). But
But one good thing about internet is that you can learn and read a lot of informations in a few time ! So, if i have a bit understood the many shematics that i have seen, if i want a spring reverb i need another 12AX7 in the préamp part, just before the amp part, maybe with just a blend selection.
For the amp part it will be two EL84, that i would like to switch from pentode to triode (for indoor unsing ang high gain sound in low level).
What do you think about a line out and headphone jack (with level) just before the EL84, will the EF86 sound "VOX enough" if i plug it for an outdoor show where the 15w would not have been enough? I know that it won't be the same but would it be stupid to try it ?
I read that the EZ81rectifier is good part of the VOX sound, so, let's go for it too!
2 output for cabs in8 ohm
For the speakers, i will make the cab as small as possible (if it doesn't change the sound ?) and depending of my budget a Celestion Blue Alnico 12" 15W-8ohm, a WGS Black&Blue or a Celestion Greenback inside . But i prefere to keep the 15W, looks to sound really better.
As you can read i already make my mind about some element of the project and i don't know if it will be possible.
My bigest question is about the power transf, the output transf and the choke, can i use the models you can find on DIY stores or does my "options" need another model, and where can i buy them ????????????????????????????????????????????
No shems for the moment, i started thining about this project when i read this forum http://www.diyaudio.com/forums/tubes-valves/144419-some-help-advice-guitar-amp-layout.html.
Thank for your awnser , pleeeease !!!!
Really new to this, just registed, and french, so sorry for my writting mistakes i do the same in french...
I started thinking about the amp of my dreams and realised that it doesn't exist !!
So, why not trying to make it myself !?!
I would have like a kind of VOX AC15HTVH1 head, but with the look of the Night Train ( for the box i can make it myself , that's not the probleme). With a spring reverb, like the AC30, no need of tremolo and vibrato, no real need of top boost, but i'd love to have a 2 mode switch on 1 jack; a EF86 mode with pentode-triode switch, and the bright levels like the AC15HTVH1, and an another mode with the classic bright channel from AC30, withe bass-tre-hig level and a kind of switch bright - thick like the night train so 2 x 12AX7 (one would be enough ?).
I'm a real pure novice but quite curious and trying to have a no-limite state of mind about what human can learn to do when we enjoy it !! And hopefully friends of mine are really good about DIY on ther electronic parts and have the good material and tools for it (optimist but not dumb). But
But one good thing about internet is that you can learn and read a lot of informations in a few time ! So, if i have a bit understood the many shematics that i have seen, if i want a spring reverb i need another 12AX7 in the préamp part, just before the amp part, maybe with just a blend selection.
For the amp part it will be two EL84, that i would like to switch from pentode to triode (for indoor unsing ang high gain sound in low level).
What do you think about a line out and headphone jack (with level) just before the EL84, will the EF86 sound "VOX enough" if i plug it for an outdoor show where the 15w would not have been enough? I know that it won't be the same but would it be stupid to try it ?
I read that the EZ81rectifier is good part of the VOX sound, so, let's go for it too!
2 output for cabs in8 ohm
For the speakers, i will make the cab as small as possible (if it doesn't change the sound ?) and depending of my budget a Celestion Blue Alnico 12" 15W-8ohm, a WGS Black&Blue or a Celestion Greenback inside . But i prefere to keep the 15W, looks to sound really better.
As you can read i already make my mind about some element of the project and i don't know if it will be possible.
My bigest question is about the power transf, the output transf and the choke, can i use the models you can find on DIY stores or does my "options" need another model, and where can i buy them ????????????????????????????????????????????
No shems for the moment, i started thining about this project when i read this forum http://www.diyaudio.com/forums/tubes-valves/144419-some-help-advice-guitar-amp-layout.html.
Thank for your awnser , pleeeease !!!!
all sounds very possible but a bit too much for a first time build maybe? anyway you seem set on doing this so:
In most DIY stores transformers go up to about 50v so i wouldnt suggest that. im not sure of the best place to get them from france, but theres edcore and hammond transformers available in a few places.
as for only using 1 12 ax7, for exactly what you want im not sure it will be enough, although 1 12ax7 will be enough when you use the EF86. and if you want any distortion, you wont get alot from 2 gain stages unless you oush the amp pretty hard. sounds like youd also want to cathode bias your EL84's as its supposed to give a warmer sound, but i think in some amps vox used a mixture of fixed and cathode bias. pentode/triode switching is doable, just need to connect G2 to the plate of the pentode, you can put a 100 ohm resistor there to be safe.
as for headphone and line out, you might want a bit of EQ and filtering there as your not getting any effect from the frequency response of the speaker. and with a headphone out, youl have to mute the amp, you cant unplug the load. (at least i think so, im not too up on headphones)
as for volume outside 15w should be plenty but it might not have too much clean headroom. youl get quite a bit of crunch at full volume, but then again for what you have in mind it might be fine, it is very loud after all.
For the cab, everything affects how it sounds, size, stability, wood, open/closed back etc.
Good luck
In most DIY stores transformers go up to about 50v so i wouldnt suggest that. im not sure of the best place to get them from france, but theres edcore and hammond transformers available in a few places.
as for only using 1 12 ax7, for exactly what you want im not sure it will be enough, although 1 12ax7 will be enough when you use the EF86. and if you want any distortion, you wont get alot from 2 gain stages unless you oush the amp pretty hard. sounds like youd also want to cathode bias your EL84's as its supposed to give a warmer sound, but i think in some amps vox used a mixture of fixed and cathode bias. pentode/triode switching is doable, just need to connect G2 to the plate of the pentode, you can put a 100 ohm resistor there to be safe.
as for headphone and line out, you might want a bit of EQ and filtering there as your not getting any effect from the frequency response of the speaker. and with a headphone out, youl have to mute the amp, you cant unplug the load. (at least i think so, im not too up on headphones)
as for volume outside 15w should be plenty but it might not have too much clean headroom. youl get quite a bit of crunch at full volume, but then again for what you have in mind it might be fine, it is very loud after all.
For the cab, everything affects how it sounds, size, stability, wood, open/closed back etc.
Good luck
how ?
Hello, thanks for your really quick awnser !! How can i move this to amp and instruments? I'm new to this.
Ok, si i'll keep for the preamp 1 channel EF86 and the other channel 2x12AX7, and after that one more 12AX7 for the reverb, better?
for the transformer and choke, i've seen that hammond got a large choice of models, once i'll have my shems ready to be post, maybe i'll need help to choose it depending of the final layout configuration...
Thanks for the pentode-triode information, i'll keep in mind.
In fact, i'm looking for the warmer vox sound as possible, so i'll set the EL84 as you told me. No real need of big disto, a little bit of crunch why not but not too much, that would be nice to be able to pump the volume without having too much distortion...
Thanks for your awnser, if u see anything else i need to know before starting...
For the tube i read that at a good price the JJ models are often good one, any other suggestion ?
Thanks !!!
Hello, thanks for your really quick awnser !! How can i move this to amp and instruments? I'm new to this.
Ok, si i'll keep for the preamp 1 channel EF86 and the other channel 2x12AX7, and after that one more 12AX7 for the reverb, better?
for the transformer and choke, i've seen that hammond got a large choice of models, once i'll have my shems ready to be post, maybe i'll need help to choose it depending of the final layout configuration...
Thanks for the pentode-triode information, i'll keep in mind.
In fact, i'm looking for the warmer vox sound as possible, so i'll set the EL84 as you told me. No real need of big disto, a little bit of crunch why not but not too much, that would be nice to be able to pump the volume without having too much distortion...
Thanks for your awnser, if u see anything else i need to know before starting...
For the tube i read that at a good price the JJ models are often good one, any other suggestion ?
Thanks !!!
I've moved to Instruments and Amps 🙂
You can use the report post button to request this sort of thing. little red ! in a triangle in the bottom left of the post.
Tony.
You can use the report post button to request this sort of thing. little red ! in a triangle in the bottom left of the post.
Tony.
You have some reading to do (okay, a lot of reading). Every tube has a purpose.
http://www.freewebs.com/valvewizard/index.html
..todd
Hi,
A "real pure novice" is best off leaving design well alone, and building a kit,
or finding a broken valve guitar amplifier with lots of info available and
fixing it / restoring it.
On your own there are far too many mistakes you can make, and contrary
to your opinion, there is as much misinformation on the web as there is
real infromation. The simplest is usually wrong / not right for the case.
No way should a novice attempt a full amplifier, it will go wrong.
It will oscillate most probably, and you will suddenly find you need
to know everything about valve guitar amplifiers to build a good one.
I don't, see below.
Buy a working used valve guitar amplifier and refurbish / tweak it.
It will be far cheaper, safer, and more rewarding in the long run.
rgds, sreten.
I bought this used in excellent condition for far less than the parts would cost :
15W, classic 10" H|H british Invader speaker, classic spring reverb.
No building grief. Haven't touched it, because there is nothing wrong with it.
If it ever starts to go wrong, then I'll fix it, not really interested in modding it.
It simply works, and works very well, build quality is way beyond a homebuild.
A "real pure novice" is best off leaving design well alone, and building a kit,
or finding a broken valve guitar amplifier with lots of info available and
fixing it / restoring it.
On your own there are far too many mistakes you can make, and contrary
to your opinion, there is as much misinformation on the web as there is
real infromation. The simplest is usually wrong / not right for the case.
No way should a novice attempt a full amplifier, it will go wrong.
It will oscillate most probably, and you will suddenly find you need
to know everything about valve guitar amplifiers to build a good one.
I don't, see below.
Buy a working used valve guitar amplifier and refurbish / tweak it.
It will be far cheaper, safer, and more rewarding in the long run.
rgds, sreten.
I bought this used in excellent condition for far less than the parts would cost :
15W, classic 10" H|H british Invader speaker, classic spring reverb.
No building grief. Haven't touched it, because there is nothing wrong with it.
If it ever starts to go wrong, then I'll fix it, not really interested in modding it.
It simply works, and works very well, build quality is way beyond a homebuild.
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Hi, pointless disagreeing when your agreeing, I did say "building a kit" as an option, rgds, sreten.
http://www.ax84.com/p1.html does have loads of documentation. Still a lot of work for a novice.
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Sreten, good call on the laney, i was lucky with mine, managed to pick up a used one, that had just some back from the factory for a complete repair. except the one i got wasnt the reverb version... i needing something to do to it 😛
anyway back on topic.
If he was to build the amp stage by stage, channel one, then channel 2 and test it with an SS PA, should go quite well as you can test the preamp on the way. the power stage can then be done after. nothing to say a first build wont go well, its just unlikely. and im sure there isnt too much misinformation on this forum.
anyway back on topic.
If he was to build the amp stage by stage, channel one, then channel 2 and test it with an SS PA, should go quite well as you can test the preamp on the way. the power stage can then be done after. nothing to say a first build wont go well, its just unlikely. and im sure there isnt too much misinformation on this forum.
Hi,
Seems to me the full monty is wanted straight off the bat, it simply won't happen.
I agree a more measured approach of somekind is required.
I'm all for building stuff, within your capabilities.
rgs, sreten.
My practice bass amp is a Traynor, vintage circa 1960, valve 15w 15".
Again picked up for far less than the parts would cost, i should really
update the 15" driver but its not quite a standard 15" cutout.
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I agree. The amp you want to build I could probably do with a lot of time to get right. But then electronics is not new to me and I have been reading up on tube amps for the last year. Better to get a simple amp, get it going and then add or modify it to get some experience.
So far I have spent more on speakers, parts, tubes, and transformers than what I could have picked up a used Fender 15 watt tube amp.And I do not even have a working amp yet. (Mind you I have slapped together a couple prototypes as experiments.) It has been a learning experience, I do have a n oscilloscope, signal generator, and a few other toys to help me along. Starting green and thinking you will design your own amp might be a bit much to attempt for most people.
So far I have spent more on speakers, parts, tubes, and transformers than what I could have picked up a used Fender 15 watt tube amp.And I do not even have a working amp yet. (Mind you I have slapped together a couple prototypes as experiments.) It has been a learning experience, I do have a n oscilloscope, signal generator, and a few other toys to help me along. Starting green and thinking you will design your own amp might be a bit much to attempt for most people.
wow, i didn'hope to have so quick awnser !! Thank you all for that
Thank you Sreten for your information and your care. I know that's it's not an easy job to do and that there is only few chances to sound good at firts times...
Maybe i aske too much for my first project. Would it be really easyer to build if i only keep one channel, certainly the EF86 one, and the reverb ? Something like this (http://www.diyaudio.com/forums/tubes-valves/144419-some-help-advice-guitar-amp-layout.html) with additionnal settings for bass-treeble and a spring reverbe ? Can i keep the same parts if i add this ? (choke, output-power transf)
On the other hand i don't want it to be a 10 years long project to do !! And i don't have 50hours a week for this ! But as i said before i can have the tools needed (and somebody who is good in using them) to test the amp stage by stage as you said Razorrick, and really want to try to build my own, but if it's a suicide-mission i don't have money enough to play that way ..
If i finally change my mind and buy something in a shop it would certainly be a Vox Night Train 15W head, with the 12" speaker cab ( and change the speaker for a celestion blue alnico or a wgs black and blue if that's not too difficult....).
But do you think it's difficult to add the line out and/or phone outputs on the night train? And what about the reverb ? I know that i have to add a 12AX7 tube configuration , can i keep the same power set or do i need to change it ? I imagine that it would be too difficult to change for EF86 on it ?!
mmmmmm, or, maybe, ?? What about buying the night train, and building another element (kind of box ?) ,that i will plug between the head and the cab, with reverb and headphone output inside ?? is it stupid ? Will it be easier than building the amp itself ? How is this kind of elements powered ?
I already test this amp in a shop and i must admit that's it's really a nice one, easier to move than a AC15... but miss a few things
Thanks for your awnser, i didn't hope to have so much so quick !
Thank you Sreten for your information and your care. I know that's it's not an easy job to do and that there is only few chances to sound good at firts times...
Maybe i aske too much for my first project. Would it be really easyer to build if i only keep one channel, certainly the EF86 one, and the reverb ? Something like this (http://www.diyaudio.com/forums/tubes-valves/144419-some-help-advice-guitar-amp-layout.html) with additionnal settings for bass-treeble and a spring reverbe ? Can i keep the same parts if i add this ? (choke, output-power transf)
On the other hand i don't want it to be a 10 years long project to do !! And i don't have 50hours a week for this ! But as i said before i can have the tools needed (and somebody who is good in using them) to test the amp stage by stage as you said Razorrick, and really want to try to build my own, but if it's a suicide-mission i don't have money enough to play that way ..
If i finally change my mind and buy something in a shop it would certainly be a Vox Night Train 15W head, with the 12" speaker cab ( and change the speaker for a celestion blue alnico or a wgs black and blue if that's not too difficult....).
But do you think it's difficult to add the line out and/or phone outputs on the night train? And what about the reverb ? I know that i have to add a 12AX7 tube configuration , can i keep the same power set or do i need to change it ? I imagine that it would be too difficult to change for EF86 on it ?!
mmmmmm, or, maybe, ?? What about buying the night train, and building another element (kind of box ?) ,that i will plug between the head and the cab, with reverb and headphone output inside ?? is it stupid ? Will it be easier than building the amp itself ? How is this kind of elements powered ?
I already test this amp in a shop and i must admit that's it's really a nice one, easier to move than a AC15... but miss a few things
Thanks for your awnser, i didn't hope to have so much so quick !
building something like EF86->12AX7->12AX7 ->EL84 (keep it single ended for now?) should pretty simple as long as you keep space for whatever else you may want to add. its going to be a long project if you dont know what your doing. but theres nothing wrong with learning.
as for buying the amp, the speaker change is simple. and i doubt youd be able to add anything to the night train, the idea of it is its compact, not alot of room for anything especially a reverb tank or more tubes.
as for putting a box between amp and speaker, the only thing that should be here is a load. even if you use an input transformer to match the load and bring the voltage back up, you will need another power amp. you might be able to mod in an effect loop to the night train, with maybe some highvoltage MOSFETs, a source follower and a clean amplifying stage. inbetween the tone stack and phase splitter.
as for buying the amp, the speaker change is simple. and i doubt youd be able to add anything to the night train, the idea of it is its compact, not alot of room for anything especially a reverb tank or more tubes.
as for putting a box between amp and speaker, the only thing that should be here is a load. even if you use an input transformer to match the load and bring the voltage back up, you will need another power amp. you might be able to mod in an effect loop to the night train, with maybe some highvoltage MOSFETs, a source follower and a clean amplifying stage. inbetween the tone stack and phase splitter.
Hi,
I'n no valve layout expert, but neither is the guy that did that layout, I
could do a lot better, which is not saying much. That is not a good place
to start, a first attempt by someone who has never built anything electrical.
Already a lost cause IMO, all of the problems with that layout will never
be addressed, such is the price of relatively clueless originality.
People like that in the planning stage think it will be easy, they are so
wrong. Ignore such posts and check out well documented kits / designs
by experienced designers and the service manuals and / or descriptions
of classic designs, very hard to do better than the best out there.
rgds, sreten.
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why not try the fender champ project, if i remember, it has a pentode in the preamp, and in time im sure you could add another preamp stage/ more advanced power stage eventually. out of curiosity, why do you want 15 watts? just becasue the AC15 is 15 watts?
Have you the schematics for the amp you want to simulate? I've got a mass of AC30 circuit diagrams, but no two are identical; we always used to say Vox built round the components they had on hand. Depending on the reverb unit available, you might be able to get by with one double triode without a transformer - more likely one and a half.
It's basically a Mullard 5-10 circuit, with a pair of output valves (tubes) in push/pull, and the phase splitter inverts the polarity of the drive to these.
If you're building on tag board rather than printed circuit (convenient for modifications) it's a good idea to punch holes for one or two more valve holders, and leave some empty tags, for future improvements.
Est que vous avez les schemas de l'ampli vous voudrez simuler? J'ai un tas des diagrammes pour les AC30, mais il n'y en as pas deux sur le même circuit. On disait à l'époche que Vox les fabriquaient suivant les composants qu'ils avaent dans le tiroir. Suivant quelle resort on peut acheter pout le reverb, peut-être on peut s'en sortir avec un seul double triode sans transformateur, mais c'est plus probable qu'il en faut un et demi.
C'est essentiellement un Mullard 5-10 (une lampe redresseur (à eliminer), deux EL84 puissance un pour préampli et l'inverteur de phase, pour que les lampes de sorti sont poussé equilibré), et si vous le fabriquez sur 'tag board' ou equivalent, pour pouvoir faire les modifications plus tard, ça vaut le pein de fair les trous pour encore une ou deus petites lampes, el laisser des contacts non-utilisés pour les ameileurations à l'avenir.
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