So I have been working on a little submini amp, and as the ideas have come along, the project has ballooned. Thus the title, this thing can do a lot. It has a clean channel, dirty channel, triode boost (pre-clean/dirty) with bright switch, switchable tone stacks, fat and presence controls, master volume, dual power amps (high and low power), line out, line in, cab simulators, footswitchable channel and boost, and tone stack bypass. This has taken a long time to come together, and there are still details to be worked out. I do have the preamp and tone stacks all worked out, so I thought I would post some clips. I have six clips, they are clean, slight grit, clean with boost, moderate grit, kind of a vintage high gain sound and then a modern high gain (boosted dirty channel). Let me know what you think.
All of the clips were recorded PRS CE24->PODxt for cab sim and a little reverb(babies in bed is not conducive to miking up a cab)->Presonus Firepod->N-track studio. No post processing. The background noise is probably a function of how high the gain is and the fact that I have carbon resistors and it is on the breadboard. Please forgive the sloppy playing, these were done really quick.
http://www.filehosting.org/file/details/21499/tube_amp_clip_dirty_light.mp3 (http://www.filehosting.org/file/details/21499/tube_amp_clip_dirty_light.mp3)
http://www.filehosting.org/file/details/21498/tube_amp_clip_dirty_boost.mp3 (http://www.filehosting.org/file/details/21498/tube_amp_clip_dirty_boost.mp3)
http://www.filehosting.org/file/details/21497/tube_amp_clip_dirty.mp3 (http://www.filehosting.org/file/details/21497/tube_amp_clip_dirty.mp3)
http://www.filehosting.org/file/details/21496/tube_amp_clip_clean_grit.mp3 (http://www.filehosting.org/file/details/21496/tube_amp_clip_clean_grit.mp3)
http://www.filehosting.org/file/details/21495/tube_amp_clip_clean_clean.mp3 (http://www.filehosting.org/file/details/21495/tube_amp_clip_clean_clean.mp3)
http://www.filehosting.org/file/details/21494/tube_amp_clip_clean_boost.mp3 (http://www.filehosting.org/file/details/21494/tube_amp_clip_clean_boost.mp3)
Hi Brian,
I didn't hear the clips, but I'm totally awestruck by the magnitude of your accomplishment just from the description... I'm sure you'll be posting some pictures tomorrow (lol).
Sounds interesting. So which subminis did you use for pre and power amp? Are you going to post a schemo?
OK. So now that it's today, and not yesterday, give it up - an April fool's thing right?
This is no April fools, I have spent the last couple months exclusively on this project. There are probably even a few options that i forgot to mention, I just can't think of them right now.
Jered - I am using two 6021's and one 6111 for the preamp and the power amp will be two 5902's in a/b pp for the high power and the low power will either be the 5902's in class a pp or two 5672's in a/b pp. The preamp is actually based off the schematic you posted in the "inspired by the valve caster" thread, though I have taken some liberties with values and some part locations, etc.
I will be posting schematics over the course of the next several days or so (I still have to make sure they are current). Since it is such a big project, I have separate schems for booster, clean pre, dirty pre, power amp, tone stack, phase inverter, etc. Hope you enjoy this thing as much as I do.
Sorry about the bad links, let's try these:
http://www.mediafire.com/file/1dozuzdmgci/tube_amp_clip_dirty_light.mp3 (http://www.mediafire.com/file/1dozuzdmgci/tube_amp_clip_dirty_light.mp3)
http://www.mediafire.com/file/yjdgidzz1tg/tube_amp_clip_clean_boost.mp3 (http://www.mediafire.com/file/yjdgidzz1tg/tube_amp_clip_clean_boost.mp3)
http://www.mediafire.com/file/o2ygnvxtjon/tube_amp_clip_clean_clean.mp3 (http://www.mediafire.com/file/o2ygnvxtjon/tube_amp_clip_clean_clean.mp3)
http://www.mediafire.com/file/jernmho0nkz/tube_amp_clip_clean_grit.mp3 (http://www.mediafire.com/file/jernmho0nkz/tube_amp_clip_clean_grit.mp3)
http://www.mediafire.com/file/zzxijddyozn/tube_amp_clip_dirty.mp3 (http://www.mediafire.com/file/zzxijddyozn/tube_amp_clip_dirty.mp3)
http://www.mediafire.com/file/ttzndhtzzma/tube_amp_clip_dirty_boost.mp3 (http://www.mediafire.com/file/ttzndhtzzma/tube_amp_clip_dirty_boost.mp3)
Can host the clips somewhere else, maybe here?
You have to enter your e-mail adress for each clip individually, then it sounds you a link to your email. Then the link isn't working for me and I am getting jumbled text.
Wanting to hear this!
Yeah, I echo kurtlives. Try www.box.net. It takes 5 minutes to set up an account, uses a free player... super simple, fast & easy.
Sounds fantastic. Can't wait to see pics and schematics!
QuoteThis is no April fools, I have spend the last couple months exclusively on this project.
OK. Then I really am awestruck! Heard the clips, and can't wait to see more details...
Wow, that's really impressive--I'd be curious to hear it pushing a speaker cab.
I especially liked the clean and clean + boost clips. If I could build a studio amp that would sound like this and have it still be pretty small in its form factor, I'd order the parts today :)
Any chance of seeing your schematic? :icon_biggrin:
Quote from: jacobyjd on April 02, 2009, 10:26:17 AM
Wow, that's really impressive--I'd be curious to hear it pushing a speaker cab.
I especially liked the clean and clean + boost clips. If I could build a studio amp that would sound like this and have it still be pretty small in its form factor, I'd order the parts today :)
Any chance of seeing your schematic? :icon_biggrin:
The schems will come up in the next few days, I just need to make sure they are all correct before posting. Just as a note, the clips are running at 34V, but there is a ton of umph in this thing.
Even more impressive--which only makes me wonder what higher voltage will do to what is already pretty nice tone...
I have tried it at 74V and though the background noise is higher, the tone tightens up more, but still maintains its character. I plan to have a switch in this thing that will allow the tubes to run at 120V or thereabouts or at about 24V.
Ok--very cool prospect. do you just use a 1:1 transformer to run it at 120v? I'm kinda new to amps...
I'm so glad you project is nearing completion Brian, it sounds really interesting - but I can't seem to access those soundclips! Frustrating!
Quote from: frequencycentral on April 02, 2009, 12:45:15 PM
I'm so glad you project is nearing completion Brian, it sounds really interesting - but I can't seem to access those soundclips! Frustrating!
Thanks for the kind words Rick. For sound clips, try my post further down with clips (it won't let me modify my original post and remove those clips).
WOW! Very tasty sounds. I'm sitting on the edge of my seat waiting to see that build. :icon_mrgreen:
Like they said back in the late fifties when the first germanium transistors were appearing...
"Sub mini tubes are the way of the future"
So your class A p/p output is just biasing way hot?
Quote from: sean k on April 02, 2009, 03:47:55 PM
Like they said back in the late fifties when the first germanium transistors were appearing...
"Sub mini tubes are the way of the future"
So your class A p/p output is just biasing way hot?
The clips above are just the preamp, the power amp still has yet to be tweaked and tested. I have not decided if I am going to do class a pp or if I am going to do some other scheme for "low power". I am actually thinking I might either do a separate power amp using 5672's or just feeding the 5902's less voltage before I try a class a pp. But from what I understand, you can run a class a pp by just not having cathode caps to ground in your normal class a/b pp.
Alright, as promised, some schematics. This first one is for the triode boost section. This is switchable with a dpdt relay in front of the regular preamp (so that it can boost either clean or dirty pre's). You'll notice the abnormally high plate resistor of 390k. This is what i had at the time. I have tried it with 220k, but can't hear too much of a difference on the end tone, so I have left it as is. The 470k series resistor (R3) at the end is so that I don't overload the first preamp stage (it creates a voltage divider with the pulldown resistor so that it doesn't load it down too much). Yes, it should be 470k.
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/tubeboost.png)
Well, i was doing some more tweaking last night and found that with the 470R resistor in series with the gain pot on the boost, the max gain got really mushy and nasty. So I ended up playing with values and found that a 15k in series with the 100kA pot gave a max gain that was still high, but nice and tight. I think I am going to play with the cathode resistors in the high gain section to see if I can get even a little more definition out of this. I should have preamp schematics by tonight. I am also thinking I might make a couple clips of what it sounds like with my tone stacks that I have (a james and a diezel VH4). Any comments or suggestions are welcome.
Nice work Ripthorn - go ahead and have fun with that sh.t!!! :icon_wink:
Okay, here is the schem for the clean section and the bax tone stack. You will note that the output goes to tone select 1a, which is one half of a dpdt switch. This is so that you can select which tone stack will be used for the clean channel. A similar switch is implemented for the dirty channel. The output of the tone goes back to the dpdt switch, so that only the output from the used tonestack goes to the volume control. Hope you guys can use this or find it interesting.
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/tubeclean.png)
And for those of you who wanted to see pics, this is what it looks like right now :icon_lol:. I have actually rearranged it so that it all fits on one breadboard, but I'm too lazy to take a picture of that. I am still trying to decide what holes I want in the chassis I made. Once that is done, loading it up shouldn't be too bad.
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/tn_DSCN0012.jpg)
Wow, I'm impressed! can't wait for the master schematic (if you are willing to share, that is).
Haha nice! Your breadboards look similar to mine when I have a crazy tube project on the go.
Quote from: Ripthorn on April 04, 2009, 11:51:37 AM
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/tn_DSCN0012.jpg)
Sweeeeeeeeeeeeeet !! :-*
Thats looking very interesting, very neat voltage multiplier on the 1st breadboard and i love to see those croc clips in these breadboard test builds. Keep us informed of how it goes. Looking forward to a sound clip when your ready.
Quote from: svstee on April 04, 2009, 11:53:11 AM
Wow, I'm impressed! can't wait for the master schematic (if you are willing to share, that is).
I'm more than willing, it's just that I am putting it up in pieces for now because the free version of eagle cad only allows one page schems, and the master will take much more than just a single page width.
@Mick, there are some soundclips in post 6 or 7. I have managed to make the background noise much quieter. I will put up new soundclips in the next few days, I think.
Well, I put together the power amp on the breadboard earlier today and tried it through the celestion in my 25 or 30 year old marshall combo. Sounds pretty good, though there is some high frequency fuzziness that comes through that didn't when I used just the preamp. I may have to play with the power amp design or I might just need more voltage (plates were all at 40V). I need to buy the parts for my nixie supply so that I can see what some high(ish) voltages will do.
So Rick, any ideas of what can be tweaked in a pp power amp? I have 33k resistors to grid 3, 1k cathode resistor and 1uF cathode caps. Maybe I was just driving the power tubes into some undesirable distortion.
Quote from: Ripthorn on April 04, 2009, 10:58:43 PM
Well, I put together the power amp on the breadboard earlier today and tried it through the celestion in my 25 or 30 year old marshall combo. Sounds pretty good, though there is some high frequency fuzziness that comes through that didn't when I used just the preamp. I may have to play with the power amp design or I might just need more voltage (plates were all at 40V). I need to buy the parts for my nixie supply so that I can see what some high(ish) voltages will do.
So Rick, any ideas of what can be tweaked in a pp power amp? I have 33k resistors to grid 3, 1k cathode resistor and 1uF cathode caps. Maybe I was just driving the power tubes into some undesirable distortion.
Maybe you can clean up the high frequency fuzziness with a couple of grid stopper resistors between your cathodyne phase invertor and the 5902's. The bigger the value the more HF is cut. I'm curious as to how much oomph you're getting with just 40v to the plates. I'm going to try two 5902's on my Sub Zero breadboard this week, so I'll let you know how that goes. Bear in mind that grid 3 is internally tied to the cathode in 5902's.
Hi Rick, with the 5902's at 40V and fully cranked, the volume is about as loud as a TV that is too loud for normal listening. I just need to up my 1044 multiplier, though it seems to be giving me less and less additional voltage with each stage. After two stages I have 34V and after four I have 41V with a 12V input. Hopefully soon I can crank this up again and see what I get.
I set up two 5902 in PP today, using 47K at grid 2 (I don't have any 33K right now), 1K and 47uf at the cathode, and running at 145v. I used the preamp/inverter stages of my Sub Zero to drive it. Very clean. I found that it is possible to get a little more gain by changing those 1K for 470R or 100R, but this seemed to excessivley load the SMPS, the voltage dropped by about 20v and the bench supply kept tripping out. I ran my Valvecaster through it - shockingly loud actually. What ratio are you calculating for PP into 8 ohm?
EDIT: On refection, I think the bench supply kept tripping due to the sheer amount of stuff hooked up to it. Two 7327 heaters in series, two 5902 heaters in series and the SMPS. The heaters add up to 750ma alone, the bench supply is 1.5A. I guess the combination of the PP loading and the SMPS was trying to pull more that teh bench supply could give. That SMPS is certainly power hungry.
Hi Rick, I am using a Hammond 125C for my OT and am using lugs 1 and 4 into 4 ohms, which I think comes out to about 5.8k primary. I did lugs 1 and 5 (I think) into 8 ohms which is approximately 5.6k primary. I tried with plate voltages at 65V and got a significant increase over the 40V arrangement, I can't wait to see what 150V will do to it. Unfortunately, my clean volume was so much lower than my distorted, but with all the bells and whistles in this thing, I should be able to equalize out the volume pretty easily. The clean channel at max gain with max boost gives an incredible crunch tone. I love to switch my PRS into single coil mode and play Fire by Jimi. I will have to make more clips. I think I am only running 1 uF on the 5902 cathodes. I may have to increase that and see what happens. I added the grid stoppers, but not too much effect, I will keep tweaking, but I think some of it might have to do with the fact that my speaker is not the best. I really should get my cab out...
Okay, I think this needs an update after 3 months of nothing. This would have been done much sooner, but a month or so ago my three month old boy took over full time occupation of the room where my soldering station and the like is. That mean that the 3 hours worth of work that I had left took several weeks.
As an additional note, I had to trim back some of the options since I found that some didn't want to play nice with others. For example, the tonestacks can be bypassed, but not switchable (i.e. I can't route the clean channel through the dirty channel tonestack) because that would require even more relays or similar. The cab sims are external, because it is amazing how much space the vital functions took up. Anyway, enough babeling, the thing sounds great and the background noise is barely audible on the dirty channel and only a near issue when I have the boost and the dirty channel going, but what do you expect with 5 gain stages? Here are a couple pictures of it finished. I used waterslide decals for the labeling and I built the cabinet out of mahogany with cherry and flame maple accents. I will try to get sound clips up soon, all my recording equipment is in that back room and I never have a moment alone in this house, what with two little ones and all. Sorry the pics are so big.
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0178.jpg)
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0179.jpg)
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0180.jpg)
That looks amzing man :o. Great work! Makes me wanna go build one!
Wow, that's beautiful. Very, very nice job. What are the overall dimensions, roughly? I love watching these tube builds - would love to do one myself, but I always chicken out when high voltages are involved.
Those little tiny tubes ended up in that gigantic head? :P Looks great. I can't wait to hear some more clips since the ones on the first page are broken links.
Nice work!
I really would love to see a finished/finalized schem.
Also a short explanation of all the knobs and switches would be nice.
I will work on getting the schem up and current, but as for an explanation of everything, here we go:
Boost: switchable triode boost based roughly on the subcaster
Channel: switches from the initial 2 gain stages to 4
Gain I: clean gain
Gain II: dirty channel gain
The four switches between gain and the other knobs were for tonestack switching, but two of them aren't wired right now, the other two are for bypassing the tonestacks
Treble I and Bass I: a passive baxandall with gain recovery
Treble II, Mid II and Bass II: a Diezel tonestack
Eleven: gain pot for the boost stage
Lead/Rhythm switch: switches out the resistor between cathode bypass cap and ground in the boost stage (makes for a flatter boost over frequency, but also less umph)
Volume I and Volume II: volume controls for the respective channels
Fat knob and on/off switch: This switches on a low frequency boost like that in the Thor and DieFET
Presence: Negative feedback loop a la Fender and Trainwreck amps
Master Volume: Self Explanatory
On The Back Panel
Footswitch jack, effects send/preamp out, effects return/power amp in, impedance select
The dimensions of the chassis are 3" tall, 18" wide and 7" deep. The overall cab is 19" wide, 8 1/2" tall, 8 1/2" deep. I will try to get the clips recorded and hosted on an easy site as soon as I can.
Wood grain adds resonance, WoW !
I can look at it tomorrow and smile again !
Lovely work on the cabinet Brian. But where are the guts shots and schematics?
Impressive work... :icon_eek:
Thanks for all the kind words. Rick, the guts of this thing would disgust the likes of you (I have seen your perf work). I mean, this makes a rat's nest look tidy. I will see if I can get some, it involves taking the cabinet apart (that's what I get for making the chassis, some things just aren't quite square). Schems are in the works, and I actually got to record sound clips this morning, though on one of them my daughter walked in and started swiveling the microphone around on the stand, but it was my only chance. I'm at school right now, but everything will come, I promise.
I would also really like to see schem/guts.
What packages do you guys use for schematics? I have been using the free version of Eagle CAD but it only allows a single page width schematic, and if I do a master schem, it will need a lot more than one page. Maybe I will put everything into a pdf.
I'm surprised you can't fit it all on one page. I use the free version of Eagle too and I've gotten some pretty big embedded development kits fully laid out on a single page schematic in there. I'm sure no one here would mind though if you split it up into a few functional chunks and either posted them as seperate images or put them together as you said in a PDF.
Okay, the schems are going to take me a bit, but here are the soundclips. The signal path is PRS CE24 - amp - 25 year old celestion G12 - Sennheiser E825 - firepod. No processing (they are fairly quiet). The first 5 seconds of each clip I don't play so you get an idea of the noise floor (though with how quiet they are, I was hearing some noise from my computer's sound card). Please excuse the sloppy playing (I have played maybe an hour in the last week and about another hour over the last month, so let's say I'm rusty). Tonestacks are bypassed, fat switch is off, presence is maxed, gain on each channel is maxed, except on the last clip. Also on the last clip, the sound starts cutting out because my daughter started moving the microphone. You will hear her at the end asking to listen to music (she loves listening to my recordings, and feels that makes it okay to interrupt whatever I am doing, and she's mostly right :icon_lol:).
Clean Channel: http://www.box.net/shared/vvb77sxny9 (http://www.box.net/shared/vvb77sxny9)
Clean Channel w/Lead Boost: http://www.box.net/shared/izy29hdziu (http://www.box.net/shared/izy29hdziu)
Clean Channel w/Rhythm Boost: http://www.box.net/shared/4pygr0eqeq (http://www.box.net/shared/4pygr0eqeq)
Dirty Channel: http://www.box.net/shared/pkfys7phun (http://www.box.net/shared/pkfys7phun)
Dirty Channel with Lead Boost: http://www.box.net/shared/54unimbson (http://www.box.net/shared/54unimbson)
Dirty Channel Half Gain: http://www.box.net/shared/6qoz1yv3ay (http://www.box.net/shared/6qoz1yv3ay)
Wow that thing sounds great! I hope my amp project sounds 1/20th as good as that. Can't wait to see the schematic, maybe I can learn a thing or 10.
Classic Nuge Strangle Hold! I just bought and watches his Sweeden Rocks concert last night dude still rocks! Amp sounds GREAT! Nice job!
I think Stranglehold is one of the greatest guitar riffs of all time. There are very few other songs that, when they come on, I just stop what I'm doing because listening takes so much attention, it's so good.
Okay, so here are some guts, but before I do that
WARNING!!!!
The following photographs may be considered extremely offensive to some people (like Rick and his beautiful work). Some people make beautiful music with beautiful circuits; I make (debatably) beautiful music is dang ugly circuits.
With that out of the way, here you go.
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0195.jpg)
The Power Supply
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0196.jpg)
The Switching Circuit
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0198.jpg)
The Big Picture
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0199.jpg)
Positive and Negative voltage multiplier (+/-17V from one TC1044)
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0200.jpg)
Bottom of Preamp Board
(http://i652.photobucket.com/albums/uu242/im_off_my_rocker/Amps%20and%20Stompboxes/DSCN0201.jpg)
The preamp board was a beast. I etched it, but the right side of it didn't heat right, so the copper tape was supposed to work, but didn't work as I thought, so I had to improv and it was not pretty.
Hey man, if it works, it works. I think it's a "different kind of beautiful". :icon_biggrin:
I am curious, though - and if this sounds like hatin' that's not how it's intended - why did you decide to do the subminis in this case? I kind of get the interest in submini tubes for pedals, for size reasons, but with a chassis and cabinet that big, why didn't you want to go for full size tubes?
The main reason is because my wife didn't want me working with 400V+, the ~120V in this thing is about as high as she wanted me to go, since when I started she was pregnant with our second. I do plan to do a full size one at some point, but for now, they offer her peace of mind so that is a good compromise for me.
It's interesting and cool that your wife pays enough attention to your hobby that she knows about high voltage. Occasionally I mention electronics stuff I'm working on to my girlfriend - her eyes glaze over and she says "Neat." before I even finish my sentence.
I was wondering if you managed to get the final schematics finished for this project? I'd love to see them.
Congrats on a fantastic build, the cab is stunning and the clips sound amazing.
Owen