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Post by cynical1 on Oct 24, 2011 20:49:39 GMT -5
I've seen a few simple tube preamp kits out there that look interesting. Years ago the guitarist I played with swore by his tube preamp, although I have no recollection of what he plugged it into.
My question is this. Is there any advantage or benefit that can be had by running a tube preamp into a solid state head?
I know this sounds like putting caviar on dogcrap to some of you out there, but I'm still curious.
Happy Trails
Cynical One
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Post by JohnH on Oct 24, 2011 21:01:42 GMT -5
I dont see why not, and there are plenty of hydrid amps with SS output stages that amount to just that. Keep the head clean and get the tone from the preamp.
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popsaka
Meter Reader 1st Class
I'm tired a'playin' so low...
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Post by popsaka on Oct 25, 2011 18:53:02 GMT -5
...Even some tube amps have horrid frequency power bands and decay so fast you go: ''which way did he go george?'' I have an ancient little Raymer 10 watt made for a small school (or) and tho' I'm afraid to crank it for fear I'll blow the output transistors (its almost 50 which is like a thousand in crappy solid state equipment years) its pretty nice -just my 8-16vdc compressor and it sings. (Early EMG type passive black HB's) I s'pose its the old saying: 'ya never know 'till ya try it' -all the amp has is hi-lo imp. switch and a tone control-
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Post by cynical1 on Oct 27, 2011 17:45:43 GMT -5
OK, after much digging and reading and searching I've come to the conclusion that there must be no market for DIY tube\valve preamp kits. So, I wandered back to the AX84 site referenced somewhere in another post that escapes me at the moment. There I found three potential candidates for further study: Simple PreampClean PreampBlues PreampThe links above all go to the respective .pdf schematics. I don't pretend to be an expert reading these, nor am I any type of authority on tube amps\preamps. I did notice that the Clean and Blues preamps both have more complexity then I believe I need for my purposes. And the Blue preamp uses 7199 tubes, which I can only assume are more expensive and harder to source. I grasped part of the triode\pentode article...about enough to suspect I don't want to go this way on this project. The Simple Preamp seems to be more in line with my skill level and desired outcome for this little venture. I know I'll have to add additional circuitry to these plans for a true standalone preamp, but it seems this is probably my best option to pursue as no complete kits are available in the price range I can comfortable cover. Any thoughts, cautions or WTFs that need to be passed along here would be appreciated. Happy Trails Cynical One |
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Post by newey on Oct 27, 2011 18:35:00 GMT -5
Don't know what your price range is, and I've never ordered anything from Paia, but they've been around forever so they must be doing something right. A pre-engineered kit, even though it may have more features than you really need, will still be easier than DIYing the whole shebang. The mono version uses a single 12AX7 and goes for $94, plus $32 if you want the fancy faceplate.  Paia TubeHead Paia Stack in a Box |
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Post by cynical1 on Oct 27, 2011 20:39:53 GMT -5
I saw those in my travels, but they don't give you a tremendous amount of information or specs on them. The Stack in a Box tended to get poor marks, but the Tube Head device did get a few favorable comments.
What I have been able to find out is they are low voltage units. Again, I'm no expert, but if I wanted a low voltage tube unit I could just grab any number of the stomp box varieties out there and be done with it.
My goal is not just to achieve a crunch or distorted tone. I'm looking for more of a warmer tone that I can put some Fender rather then Marshall drive to if necessary. Unless it just proves untenable, I'd really like to stay with the traditional high voltage units if possible.
And I agree with newey completely that this isn't some simple stomp box adventure. These voltages can kill you at worst, and give you a very bad day if you get off easy. I have a healthy respect for high voltages. I won't be putting this together today or tomorrow, so I have plenty of time to research this thing out and have a better understanding of what I'm doing and why.
Happy Trails
Cynical One
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Post by sumgai on Oct 28, 2011 2:13:28 GMT -5
c1, Technically speaking, just copy the first stage of any tube guitar (or bass) amplifier. The same power supply from that unit can also be used, scaled down in terms of capacity, or a new one can be devised (stolen from other sources....), that's easy. Many players believe in the magic of tubes, and go out of their way to implement them in various degrees. (Partial, as you're contemplating, or fully, as in no SS at all.) You're in good company here, so don't feel like you're the lead sled dog.   So long as you remember, and practice, ChrisK's One Univeral Truth, you'll be fine. ..... Oh, you wanna know "which" one that is? You think he had more than one? Nope, only one - "Someone is always the fuse - make sure that someone isn't you!" Chris said lots of other things, but none of them were on the same level as this statement. IMHO, of course.  HTH sumgai |
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Post by newey on Oct 28, 2011 5:49:23 GMT -5
Or . . . .Hit Ebay, buy a small tube head like a used Epi VJ, and just bypass the power amp section, out to a jack. Quick, easy, and probably less than you could build one for. I see those VJs go for $70 or so with some regularity, and there are other models of small tube head as well.
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Post by cynical1 on Oct 28, 2011 7:10:25 GMT -5
Now that has serious potential as a learning experience. I like it. And it's easier collecting the insurance money after the fire if you can point to something with a brand name on it versus something you DIY'd as the cause... I haunted the public library sale last week and found a few old books on tube amp designs for hi-fi sets, so I can absorb a bit of theory here along the way. At least the terms and definitions are starting to make sense. I haven't gotten to that part yet. How would you scale down a the power supply safely without generating excess heat? Yes, I remember that one. I used to play with old radios and record players as a kid trying to make some sort of amplification device out of them. Most I just made blown fuses, but I got my share of hits out of them. My intention here is to keep it safe, functional and cheap to operate by keeping the tube count to a minimum, but still powering at higher voltages to gain the headroom out of the preamp. If it works for the guitar I may try another one for the bass. The solid state head is a bass head, which works for both instruments. It just needs a little help with the guitar. Thanks for shortening the learning curve...especially as I don't have the hair to stand up on end like I used to... Happy Trails Cynical One EDIT: Question. How involved would it be to make the preamp stage(s) of say the Valve Jr. switchable? By this I mean would it be more trouble then it was worth to bypass the power stage and take the output from the preamp out to another head, but still allow it to be switched back to a functional standalone 5 watt amp for practicing or lower volume applications? Make sense? In other words, is it more then a switch, a jack, some wire and maybe a pot to pull off? |
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Post by sumgai on Oct 28, 2011 13:43:36 GMT -5
Question. How involved would it be to make the preamp stage(s) of say the Valve Jr. switchable? By this I mean would it be more trouble then it was worth to bypass the power stage and take the output from the preamp out to another head, but still allow it to be switched back to a functional standalone 5 watt amp for practicing or lower volume applications? Make sense? In other words, is it more then a switch, a jack, some wire and maybe a pot to pull off? A veritable no-brainer of the first water. No switch needed, unless it's to silence the internal power amp/speaker whilst feeding an external power amp/speaker(s). In such a case, the "pre-amp out" jack could do double duty, acting as both a signal source and a switch - Voila! the smallest parts count possible, given the described operational functionality. I don't think another pot is necessary. If you want to control the drive into your bass amp, simply use the existing Volume control on the Epi. Unless you intend to use both at the same time, then your extra pot would probably be handy.  All that remains is the cost versus desired tonality versus time.... As they say, you can have any two out of the three! ;D HTH sumgai |
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Post by newey on Oct 28, 2011 15:54:29 GMT -5
This is basically like adding an effects loop, as I see it. In fact, if you could find a small tube head with an effects loop, no modding needed- just go out from the "effects send "out to the SS power amp, and insert a plug (not wired to anything) into the "effects return" as that jack is usually switched so as to avoid possible damage to the amp if the FX loop isn't plugged in.
I think that would also work, although the power amp might not like running without a load on the front end, not sure on that.
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Post by cynical1 on Oct 28, 2011 19:08:59 GMT -5
The more I think about the idea of making a switchable amp\preamp from a small tube amp the more I like it. My inital goal was to give the overdrive pedal something to overdrive, but this seems like something much more useful.
The solid state bass head sounds good to a point with a guitar, but it seems that solid state has a quick ramp to overdrive, then it just seems to shelf out. I don't know how else to describe it, but it seems to go from 0-60 real quick, then stay governored at 60. I never consciously tried to overdrive anything on a bass. Call it old school, but I just never liked the sound of an overdriven bass. This made solid state very agreeable for me and saved me a car payment buying tubes constantly.
In the few short months that I've been torturing guitar strings I notice that it's a different world over here in this octave. I went to GC and tried a few middle of the road tube amps and was amazed at what they sounded like with a guitar similar to mine. After I blazed through my obligatory dozen chords and half dozen scales I was out of material, but it was enough to see that all the voodoo you guys go on about with tube amps does hold water with a guitar.
This got me thinking about the old tube preamp my guitar buddy used decades ago. I don't have the 1%'s disposable income, so a preamp kit seemed in order. Just something for the tube overdrive to actually overdrive.
And I've tried the overdrive pedal through the effects loop and on this amp it leaves something to be desired. The modulation effects work well in the loop, but the overdrive really needs to be at the front end to works its magic.
And the idea of a 5 watt tube amp for recording seems to be just the ticket as things will likely be changing in my recording venues over the next year or so.
One question. On the preamp schematics that I can understand, there is a B+ and B- out to the power amp stage. Do I need to do anything about that when the preamp is out of that circuit? And are there any protections I should put in place to prevent a surge or pop when switching back and forth. Not a big fan of that sudden whiff of smoke...
So, I'm watching the Valve Jr's on eBay. Any other likely candidates for this little science project? Preferably along the lines of 5 watt non-boutique units...
Happy Trails
Cynical One
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Post by newey on Oct 28, 2011 19:44:53 GMT -5
Kustom has a 5 watt head, the Defender 5H for $99 new. Don't know about a used one as they're fairly new. Also brand new, and only a bit more at $119, is the new VOX AC4TV mini, which isn't just a head but also has a 6.5" speaker. However, it has a speaker out so extension cabs can be used. VOX AC4TV miniBugera also makes a small hybrid with a 12AX7 preamp and a SS powersection, with an 8" speaker, for around a 100 bucks. |
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Post by jcgss77 on Oct 29, 2011 11:26:25 GMT -5
C1, you don't need to worry about protecting the tubes. As some Gai told me a while ago, they are tough little buggers. They will take what you can dish out to them, as long as you don't let the heaters get more than the 12.6 volts they so desire.
I am not sure, however, about just bypassing the power tube. I am thinking some kind of switching will be necessary make sure no voltage gets past the preamp tube in the amp. I know that tube amps don't like to run without a load on the output, so I am thinking set up something that will re-route not only the signal path and ground to your bigger amp, but also the main Voltage and ground of the rest of the amp. I would recommend that power go disconnected past the preamp tube, and the ground stay connected for safety's sake.
If you want to really get your hands dirty, you can make yourself a low-voltage tube preamp known as the Valvecaster, and then up the voltage by means of a multiplier, charge pump, or other such device. If you would like to go this route, and use the multiplier, I would suggest chassis grounding. Maximum protection for those who play in their socks...
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Post by cynical1 on Oct 29, 2011 15:00:37 GMT -5
I am not sure, however, about just bypassing the power tube. I am thinking some kind of switching will be necessary make sure no voltage gets past the preamp tube in the amp. I know that tube amps don't like to run without a load on the output, so I am thinking set up something that will re-route not only the signal path and ground to your bigger amp, but also the main Voltage and ground of the rest of the amp. I would recommend that power go disconnected past the preamp tube, and the ground stay connected for safety's sake. This was the direction I would like to go. I'd even go so far as to rig up separate power switches to turn on the preamp and power amp stage separately. This may be overkill, but over-engineering things runs in the family. While I've been burning brain cells reading everything I can on this stuff, I think it will all make more sense when I have something I can physically see and touch...powered off and discharged, of course... There seem to be a load of different modifications out there for these Valve junior amps, so this may turn into the ever expanding project. That's an idea. I'd be more comfortable with it if I knew more about tube amps and their little idiosyncrasies. I figure if I'm in this for the learning experience then starting out with a proven design and making surgical strikes along the way might keep me from inadvertently re-inventing the defibrillator. HTC1 |
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Post by JFrankParnell on Nov 1, 2011 16:09:26 GMT -5
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Post by cynical1 on Nov 1, 2011 17:49:28 GMT -5
I looked at the modeling amps and low voltage tube effects, but the more I read about tubes and tube amps, the idea of running them low voltage strikes me as something akin to buying a Ferrari and only running it in second gear. I realize the preamp stage is much lower voltage, but having the flexibility to switch between the preamp and full amp for either playing out or recording strikes me as the best mileage I can get for my dollar. Plus, having had a modeler die on me, and take all my effects with it really sucked. The biggest drawback for me is the fact that the modelers do not allow quick changes on the fly. With the bass I never really cared, as I never did a lot with it on the fly anyway. If I was going to make a change for a song I just saved another preset. I only had about 5-7 presets in the modeler for the bass. The first month on the guitar I must have burned close to a dozen, most of them just subtle changes from a core group of effects. Down the road I may grab a modeler again to experiment with. I've heard what they can do and it is impressive. The Valve Junior seems to have a load of mods available, and after spending a week reading as much as possible at Sewatt V-J Mods this looking like the way I'm going to go in the end. [Way Off Topic] And as far as the 1% versus the 99%...after this whole wind farm debacle and seeing how policy can be coerced out of politicians if you threaten to throw enough money against their re-election campaign...man, don't get me started... The signs and the camping out is a start. But until the mobs with torches start marching across the broad finely manicured lawns of the 1% nothing will change. Egypt has no government, is still controlled by the military, Mubarek has yet to see a day in court and the people remain camped out in the park. Libya is free. I think the lesson is obvious. [/Way Off Topic] Well, that's far enough off topic... Happy Trails Cynical One Less sedation and more sedition. |
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Post by newey on Nov 1, 2011 19:47:03 GMT -5
Well, at least someone is finally yelling at the right people . . .
Back on topic, I get an "access denied" message when I click on the link to the V-J mods.
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Post by ashcatlt on Nov 1, 2011 20:20:59 GMT -5
Did you mention what speaker cabinet you're running this thing through?
The dirty secret that very few people dare to discuss is that tube distortion sounds just about as nasty as solid state distortion, and needs the same sort of filtering to make it listenable. You won't probably enjoy the sound of the pre direct into the recorder until after you apply a speaker simulator. For the same reason you probably won't like the sound of the pre-amp into one of these modern bass amps with the piezo or horn tweeters. These are far too flat to sound decent with guitar.
Luckily, analog cabinet modeling is fairly easy, and there are a number of established designs out there.
It never occurred to me to use the effects in the V-Amps. I do use a little of the pre-amp compression on the Bass versions, but otherwise I use the thing like the amp it's emulating. If I was playing through a real AC30, the delay would have to come before the amps overdrive and speaker/cabinet filter. Likewise the chorus and whatever else I decide to use. Also, I wouldn't likely stomp on a pedal to solo through my Soldano stack. Id maybe just step on a booster or a Rat run into the Vox. But that's just me.
BTW - I just ordered an AC4. I played one for a couple minutes at a store a while back and have been kicking myself for not buying it. I'll have it next week sometime.
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Post by cynical1 on Nov 1, 2011 21:18:08 GMT -5
By default, the bass head runs through a 2x10 cabinet with an HF driver horn. The horn can be boosted, cut or bypassed. It's odd, but I have the horn up about 2/3 of the way on the bass, but barely in the loop for the guitar. I thought it was odd at first, but what you said makes sense, so I guess it's not just me.
I had a chance to borrow a Champ clone from one of my co-workers. He builds these things, along with other high end audio and performance equipment, and after several discussions on solid state versus tubes he just dragged it in and said "...play with it for a weekend and come back to me about how good solid state is..."
It took a bit to get used to it, but the first thing that struck me was the longer ramp into ugly. Probably a bad term, but it seemed I had more latitude to drive the amp before it just turned to distortion for the sake of distortion. And obviously, the Hardwire overdrive did exactly what it was designed to do by driving the tubes in any number of interesting directions.
By Sunday afternoon I was trying an A/B unscientific test and found that the solid state amp had a much shorter ramp into distortion, where the tubes gave you more room to tweak.
And I just never liked direct recording of anything, and direct digital is just too flat and sterile for me. I've been using a mic on a cabinet for 30+ years on 99% of the stuff I've recorded and don't see myself changing that. Jimmy Page used low watt amps in the studio for quite a few of the Zeppelin tracks. Based on the quantity of his session work with a 3-5 watt amp I see no reason not to move down the same path.
And I admit I am a sucker for the effects send on the bass amp. I can overdrive the signal on the way in, then put the chorus, flange and delay through the effects send. This is the first amp I've had with an effects and I'd miss it if I lost it.
And one day I may have to drop some coin on a Rat. Right now I really just need to practice more, but with some of the mods for the Rat that I've read about I might just have a place for one down the road.
Happy Trails
Cynical One
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Post by cynical1 on Nov 1, 2011 21:44:58 GMT -5
Back on topic, I get an "access denied" message when I click on the link to the V-J mods. Yeah, you actually have to join to see anything. I should have thought of that when I put up the link. Sorry about that. I've been haunting the place off and on for a little while and the V-J section is just one small little corner of their forums. But for my intent it's perfect. There's even spreadsheets that detail every component in the amp, what their purpose is and how you can swap them for either a Fender or Marshall type of tone. The one thing I have learned for sure is how much I don't know about tube amps. [Off Topic...again...] Yelling leads to two things...anarchy or a sore throat. Just like a horse isn't thinking at a dead run, people tend not to think while they're yelling. Instinct is not reason. The problem is obvious. Articulating a solution and taking action, while generally avoided due to the inherent pain and sacrifice involved, is another matter. Sadly, from my experience, the one that stands up merely makes a better target of himself or herself. I guess when enough of us have nothing else to lose maybe then someone will step up and be followed. Dissatisfaction should never be mistaken for dissent. [/Off Topic] Happy Trails Cynical One |
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Post by Yew on Nov 10, 2011 7:51:49 GMT -5
BTW - I just ordered an AC4. I played one for a couple minutes at a store a while back and have been kicking myself for not buying it. I'll have it next week sometime. I Liked the AC4 when I played it, but thought it could have done with a gain knob, to get decent overdriven sounds at decent neighbor friendly volumes. @cynical, If you are doing any wiring inside a VJ, you may as well put a gain knob on it (maybe even a basic tone control) as its a reasonably simple operation, and there are plenty of schematics out there. So that if you find yourself jamming round at a mates, you can just take it and a cab, instead of a whole bass amplifier. Personally I think that if I get a bass (probably some epiphone EB thing) I would make sure I have at least one valve stage, to get that 'bloopy' Andy Fraser sound. (maybe I could run my tiny terror into a bass cab? Or even its internal speaker?) |
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Post by ashcatlt on Nov 10, 2011 15:52:45 GMT -5
Well, mine has the attenuator switch. The 1/4 W setting isn't too terrible loud. Maybe a bit much when people are sleeping in the house, but I've got amp modelers for that. I got it now because the Rock and Roll Kamikazee is happening. I've been "randomly" assigned to work with four other local musicians, and this thing is easier to bring to practices than a V-Amp + PA. I also wanted it for recording. Figured Dave would want to use his real amps (since I force him to play a modeler on stage) and I wanted to get in on the action. Course now that he's quit...
I think you're talking more about a Master Volume config.
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Post by thetragichero on Nov 10, 2011 15:56:27 GMT -5
how involved are you looking to get with it?
awhile back when my marshall's preamp wasn't working (for some unknown reason) i had started to make a rackmount preamp based off the marshall jcm 800 2204. i found that a reverb driver transformer fit the specs for just the preamp tubes in it, but i didn't get very far in the actual construction stage before something else caught my interest
if i remember correctly, i took the schematic for the jcm 800 up to right before the phase inverter, and was going to snipe the tl072-based fx loop buffer from the 1987x reissue (whether or not it would be needed , i'm not sure, but figured getting the impedance suitable to run fx between that and the power amp would be a good thing)
just a thought... the jcm800 circuit is rather simple compared to any of their later series... i still have the big electro caps and transformers that i'd probably be willing to let go for cheap if you wished to go this route... and most of the resistors and caps and pots i was going to use as well
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Post by 4real on Nov 10, 2011 16:27:06 GMT -5
I used to like the idea and want to build some kind of pre-amp into a solid state system of some kind at various times over the years. What I have consistently been hearing is that tiny pre's are using those tubes as little more than fancy LEDs, especially those in things like effect boxes...some even have an LED behind them to make them glow...because they are running cold. Trading off the whole tube mojo thing. There seems to be quite a lot of the tone of tube amps from the power amp section too...a small amp is going to allow you to push things a lot further to capaitalize on such effects, it wont be present in a pre-amp. But I am sure there are decent preamps about all the same... For tens of years and always playing in bands I used a solid state amplifier. It's still here and sounds good, but it is super clean by nature (roland) and it does not have the immaculate tone and character of a tube/valve amp (we talk valves in the colonies)... In fact, I used that up to about 5 years ago when i treated myself to a fender hot rod deluxe. I love that fender sound and it does that well, is the most popular amp apparently. I got mine second hand but 'as new' having never left the house of the guy for half price. Particularly on the clean channel, it has a great tone...pedals would dirty things up but I tend to play clean these days. But, you have to worry about these things...they are full of glass bottles, expensive and heavy and steal-able....hmmm. I had a scare not long back when i discovered the amp and guitar were not covered in the back of my car...driving 100kms to jam at the time (each way) every week, I could just see someone rear ending me at 100km and take out the amp and the car...or a malicious roo, got a few of them out here. ... They are not 'the same' but a good modelling pedal really is something to consider these days...all of these things need quite a bit of editing for your guitar and the amp it's feeding and your sounds and touch, but they do a decent job and can often work well into a recorder. Few generally need anything huge, especially if you like the overdriven tube sound...that is the LZ thing, the old supros are still a bit of a cult and although these small amps were low watts, they moved a fair amount of air. You do need to get louder than a drummer generally or have that capability. There are so many of these pre-amp kits and such...there probably is something to them, but perhaps they are working more like a distortion box as much as anything else. ... If you are keen to add a bit of 'tube mojo' in a cheap and compact form to get your feet wet, perhaps something like this for $30 might be considered...  secure.oatleyelectronics.com//product_info.php?products_id=955&osCsid=8433d9cd5a84a25664dcbf56747b76ecor a stereo version... secure.oatleyelectronics.com//product_info.php?products_id=885which includes a PDF... secure.oatleyelectronics.com/files/K272A%20NOTES.pdfReally though, i'd always been led to believe that a lot of the tube 'magic' comes not from the preamp but the transformers, high voltages and power amp sections. One could easily make one of these things into a compact pedal I imagine, it even runs on batteries and draws very little power really...form the PDF they recommend for guitars the K270 as it has some filtering. ... But remember the guitar word is full of mojo and although a tube amp is great, it is not nirvana and modelling and other strategies may well get you better bang for buck. If not wanting to play 'loud', a small valve amp will do the trick more than a pre would I suspect. Anything more than the 40 watts in my fender is probably wasted unless you are playing in a band and want to drown out the drummer. One thing that I always used to do to get a biger sound was to add more speakers...I still have for such purposes a 15" ported bass box and with a 12" combo can get a massive 'wall of sound' and kind of 'crossover' effect and move a lot of air over a wider area. I used that back in the 80's 'who' like band I was in as we never had a PA enough to do more than vocals and a very loud drummer and needed to create a 'wall of sound'. The best sound I got was an old tube amp into the bass box and the SS amp in stereo...monstrous tone...so much that I had a kid banging on my door wanting to see me play purely for the sound it was getting on the one time I tried it LOL. Having been 'shocked' by dodgy set ups, once in the mouth while singing on a gig, I tend to steer away from such things these days. ... Anyway, don't get too carried away with all this stuff as the next thing you will know you will be coveting bumble bee tone caps for your guitar and vintage spec cloth covered wires... |
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Post by morbe on Jul 13, 2012 14:42:07 GMT -5
You know I have thought about this as well. You can buy solid state amps off the web. Really cheap DIY kits, I wonder if there is a way to build a pre amp and connect it to the solid state amp. And make your own hybrid? Or they may be kits for this already I dunno?
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Post by sumgai on Jul 14, 2012 12:27:03 GMT -5
morbe, You know I have thought about this as well. You can buy solid state amps off the web. Really cheap DIY kits, I wonder if there is a way to build a pre amp and connect it to the solid state amp. And make your own hybrid? Or they may be kits for this already I dunno? As noted several times, there are kits for going whole hog, or for making only one section or the other (pre-amp or power-amp), then combining them on your own. Or you can whomp up a passel of parts and roll your own, so to speak. However, as pointed out here: ......
Really though, i'd always been led to believe that a lot of the tube 'magic' comes not from the preamp but the transformers, high voltages and power amp sections. 4 almost nails it. The Real Mojo™ (not to be confused with 4real's own personal Mojo!) is the interaction between the speaker and the output transformer. Part of that is due to what are known as "eddy currents" within the transformer as it tries to keep up with converting high-current electron flow into a magnetic field and back again, and the other part is where the reconstituted electron flow from the transformer's output is converted into kinetic energy by the speaker. Each of these conversions, and both of them together, lead to some slight distortion of what we started with, a signal from our amplifying devices (the tubes and associated components). And that slight distortion is what we're hearing when we say "manochevitz, has he ever got The Tone!" And all of that is before we even begin to consider such things as loading, damping, back-EMF and other assorted esoteric criteria in deciphering what's really going on, and discerning why pedals (and any other pre-ampish type of distortion) don't quite cut the mustard. They may be close, but just like in hot-rodding your car, there ain't no substitute for cubic inches!  In short, if you want the Real Meal Deal, you have to hire a roadie to haul around your back-breaker of a tube amp and speaker cabs. If you're willing to settle for 90-95% of that sound, then solid state will fill the bill, and you can save on having to buy your roadie so much beer at the gig! HTH sumgai |
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Post by thetragichero on Jul 31, 2013 0:40:22 GMT -5
resurrecting another dead thread but... trust me, using an off the shelf working amp (valve jr, etc) for its preamp into a power amp is the way to go. i have a Marshall head that used to have a busted preamp(somewhere... local shop couldn't figure it out...) that i thought the proper solution was to build a preamp clone of a jcm800 to run into. needless to say i have almost $300 in components and the 1u casing for it sitting on my bench....
edit: hey i replied to this two years ago with much grander aspirations. used peavey rockmaster preamp off ebay ended up being my solution...
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but, these little jobbies are really cool and should be fairly inspiring to you as a new 6stringer. I guess you've got at least one bass amp, and that is perfect for running a modeler into. Or if you have a PA in your space, that works perfect as well. As for recording, thats what I've used on everything I've posted in here.
