That sounds excellent. Hard to say how much of the good sound comes from the Egnater (valve) amp, and how much from the solid-state pedal, though.
So far, the Sansamps and clones (Joyo American Sound, etc) are the best-sounding solid-state guitar amp emulations I've heard. I have an American Sound, and it isn't horrid even played straight into a solid-state P.A. It's not anywhere near as good as your little 2W 5E3, though!
-Gnobuddy
So far, the Sansamps and clones (Joyo American Sound, etc) are the best-sounding solid-state guitar amp emulations I've heard. I have an American Sound, and it isn't horrid even played straight into a solid-state P.A. It's not anywhere near as good as your little 2W 5E3, though!
-Gnobuddy
I hadn't heard of that one, thanks for mentioning it here. Some of the videos of it sound pretty good.
For a variety of reasons, I think digital emulators are the future of the guitar-amp industry. There's no magic in a valve, so it has to be possible to emulate it virtually exactly; the only question is how complex a model, and how much computational power, is necessary to do it realistically.
Computational power is becoming amazingly cheap and abundant, so the remaining weak spot is probably the actual mathematical models of valve amplification stages.
I hope they (emulators) eventually sound as good as the real thing before the bottom drops completely out of real valve amp manufacturing.
It's been a very long journey already. The first solid-state guitar amp to get any real love from musicians was probably the 1975 Roland Jazz Chorus - and it was mostly popular for its lush reverb and chorus effects, rather than it's bare tone. Forty years
later, most solid-state guitar amps still don't sound very good. That is a very long time in the world of electronics.-Gnobuddy
The Kustom amps from the late 60's and early 70's were quite popular in their day. Bands Like Credence Clearwater Revival played straight into the amp, no pedals. I had a Kustom PA that I resurrected from the dead in about 1975. I used it for my keyboards. Didn't sound bad, but you don't crank keyboards into the distortion zone. All of the Kustoms from that era used the same schematic. It came straight out of the RCA transistor manual. So did the Heathkit guitar amp. The K200's (100 W RMS) used two of the 50 W power amps in parallel.
Acoustic from the same era was somewhat popular, especially their 360 bass amp. It had the ability to throw the bass out into the crowd. It was louder out in the middle of the field than up close. Ampeg had a bass cabinet with two speakers in a wedge configuration that did the same thing.
As simulators go, I use TH3 from Overloud on a PC. It has a clean reverb surf music tone that brings me right back into the garage in 1967 playing Ventures tunes. That's the sound I was always chasing back then, but could never catch, due to lack of a real reverb tank. Can't find those in the county dump.
Acoustic from the same era was somewhat popular, especially their 360 bass amp. It had the ability to throw the bass out into the crowd. It was louder out in the middle of the field than up close. Ampeg had a bass cabinet with two speakers in a wedge configuration that did the same thing.
As simulators go, I use TH3 from Overloud on a PC. It has a clean reverb surf music tone that brings me right back into the garage in 1967 playing Ventures tunes. That's the sound I was always chasing back then, but could never catch, due to lack of a real reverb tank. Can't find those in the county dump.
The Acoustic brand was re-launched in 2007, apparently with at least one of the original designers on board. Their first two offerings (B20 and AB50 bass and acoustic bass amps) were very well reviewed all over the Internet.
Then the bottom fell out of the American economy, yanking much of the rest of the world with it. Acoustic seems to have been absorbed into Guitar Center and become a house brand. Guitar Center itself is in financial trouble, so who knows what the future holds.
I still have a B20 bass amp. I think I paid $120 or so for it, new, circa 2009; pretty close to a "hundred buck guitar amp", albeit for bass guitar. It produces surprisingly good bass tone from it's 20 watts and big 12" speaker, and even copes well with the low B on my 5-string bass.
I also have a later Acoustic product, the AG30, a wedge-shaped, dual-input acoustic guitar amp/small P.A. Only 30 watts and a slot-loaded 8" woofer with coaxial soft dome tweeter, but it has very nice sound quality, far better than a lot of P.A. systems that cost far more, and it's been more than loud enough for my use. It's used for vocals, and acoustic guitar amplification; strictly clean, of course, no overdriving or clipping, ever.
These were both thoughtfully designed products, where the money was budgeted well, and spent where it mattered most, on sound quality.
I am not sure about the causes for the brief flirtation by mainstream guitarists with solid-state guitar amps in the 70's and 80's. Perhaps those musicians talked themselves into believing the new transistor technology sounded better? Or perhaps it had something to do with impaired judgment due to all the illegal chemical substances floating around in their bloodstream?
Certainly there seem to be a lot of out-of-tune, out-of-time, nasty-sounding recordings from that era, probably from musicians who were stoned out of their minds at the time of the performance.
-Gnobuddy
The electronics of my amp are almost done - but there is one last piece of the puzzle missing. I really want to have an effects loop. Gotta have some reverb and delay after that distortion!
The loop doesn't have to be all-valve. Solid-state is fine as long as it contributes no audible distortion (i.e., is kept out of clipping, and produces less than 1% THD). But it must respect the basics of audio electronics: reasonably low source impedance on the "send" side, and enough clean gain to bring the levels back up, post-stompbox.
With two independent preamp channels, and very little room left on my plywood circuit board, I am momentarily stumped as to how to manage this. My initial ideas quickly evolve into absurd levels of complexity, and then get discarded. I haven't found a simple approach, yet.
I have +150V and -75V rails in my power supply, and a few LND150 MOSFETs, so that seems the way to go, but how to keep the whole thing simple?
I am also thinking parallel effects loop; less chance of ruining the basic sound of the amp that way, I think.
Anyone else have any suggestions to offer?
-Gnobuddy
The loop doesn't have to be all-valve. Solid-state is fine as long as it contributes no audible distortion (i.e., is kept out of clipping, and produces less than 1% THD). But it must respect the basics of audio electronics: reasonably low source impedance on the "send" side, and enough clean gain to bring the levels back up, post-stompbox.
With two independent preamp channels, and very little room left on my plywood circuit board, I am momentarily stumped as to how to manage this. My initial ideas quickly evolve into absurd levels of complexity, and then get discarded. I haven't found a simple approach, yet.
I have +150V and -75V rails in my power supply, and a few LND150 MOSFETs, so that seems the way to go, but how to keep the whole thing simple?
I am also thinking parallel effects loop; less chance of ruining the basic sound of the amp that way, I think.
Anyone else have any suggestions to offer?
-Gnobuddy
Yikes. I hope I didn't kill this thread for good.
Anyway, here's my first attempt (simulated in LTSpice) at an FX loop. One LND150 to buffer the signal from the master volume pot, a passive FX send using a tolerably low impedance (10k) pot, a second LND150 to bring the "wet" signal from the FX loop back up to its original level, and mix it with the dry signal if desired.
The second LND150 operates as a crude virtual earth mixer. With up to 150 volts p-p of headroom, it should never clip in use, so it should be completely inaudible in the amp.
There are an annoying number of controls: master volume in the preamp, and then, in this FX loop schematic, an FX send level pot, and a "Dry" send level pot. I'll probably need to add an FX return level pot too, or at least a switchable pad in case return levels are too high.
3 pots, 2 MOSFETs, 2 quarter-inch jacks, a slew of resistors - this FX loop circuit is more complex than an entire classic Fender preamp. And this is after a few days of trying to simplify, simplify, simplify!
LTSpice screenshot, and .asc file attached. Comments, suggestions, and constructive criticism will be gladly received.
-Gnobuddy
Anyway, here's my first attempt (simulated in LTSpice) at an FX loop. One LND150 to buffer the signal from the master volume pot, a passive FX send using a tolerably low impedance (10k) pot, a second LND150 to bring the "wet" signal from the FX loop back up to its original level, and mix it with the dry signal if desired.
The second LND150 operates as a crude virtual earth mixer. With up to 150 volts p-p of headroom, it should never clip in use, so it should be completely inaudible in the amp.
There are an annoying number of controls: master volume in the preamp, and then, in this FX loop schematic, an FX send level pot, and a "Dry" send level pot. I'll probably need to add an FX return level pot too, or at least a switchable pad in case return levels are too high.
3 pots, 2 MOSFETs, 2 quarter-inch jacks, a slew of resistors - this FX loop circuit is more complex than an entire classic Fender preamp. And this is after a few days of trying to simplify, simplify, simplify!
LTSpice screenshot, and .asc file attached. Comments, suggestions, and constructive criticism will be gladly received.
-Gnobuddy
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My latest project has 53 knobs and a "test" button. It however cost a bit over $100, but that does include the knobs. It could be duplicated for about $100 without knobs, but I don't think we are ready for a Hundred Buck Synthesizer Challenge.
This is neither an amp, has a guitar input, or uses any tubes, but all are planned long term. My favorite "controller" is six note polyphonic, so that's the next obstacle. Polyphony requires a more powerful processor with more I/O. An advance prototype Teensy 3.6 will be headed my way soon. I plan on making a basic LCD / menu version that will fit inside the guitar.
I will be leaving for a 3000 mile road trip on Monday. This, and the new CPU go with me so I can work on the software. Sometime after my return I will start a new thread, or resurrect the long sleeping vacuum tube synthesizer thread.
http://www.diyaudio.com/forums/inst...-tubes.html?highlight=vacuum+tube+synthesizer
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Oh, boy! I can see why you had to color-code the knobs!
I hope you never have to debug any of the wiring. That would not be a fun job!
My wife has recently begun singing Cyndi Lauper's "Time After Time" at jams. I'm her accompanist, so I listened to the song to learn it, and I got a memory refresh of those 1980's synth and guitar sounds, complete with far, far too much chorus, and far, far too much use of primitive early sequencers. Oy vey!
The good news is a pair of cheap guitar pedals (chorus and reverb) got me close enough to the original guitar sounds. The bad news is that those sounds are, shall we say, not exactly subtle!
Hex pickup, or will you have to figure out all six string frequencies in software?
Good luck with the long road trip!
-Gnobuddy
I started down the synth in a guitar road twice already, three times if you count the Ebay sourced Roland GI-10, with limited success.
I have used 3 methods to track a guitar string and so far the best method has been a hybrid of all 3. All of this was done using discreet chips, no microprocessor, since there hasn't been a fast enough chip that is so easy to program that even a blonde can do it. Now that I'm learning new stuff on an hour by hour basis, it's time to dig up all of my old stuff from 6 or 8 years ago.
I use a "hex pickup," actually 6 individual Ghost Saddles from Graphtech, so you have 6 individual piezo pickups in your bridge.
Guitar Electronics, Pickup Systems | Graph Tech Guitar Labs
Their complete system was out of my price range at the time. I haven't looked at it recently. Each pickup feeds an opamp buffer. The 6 outputs can drive some MIDI interfaces, or you could use their interface to put a MIDI output on your guitar.
I fed each pickup to a MC14046 Phase Locked Loop chip, which does a reasonable job of tracking a guitar string, bends and all, but the acquisition time is too long for the low frequency notes.
I also built a wired neck using a fingerboard and fret wire from Stewart McDonald. Each string must be individually electrically isolated. It's not hard to do with the Ghost Saddles and a Lexan block for the string ferrules to rest in. Now you have essentially a 6 X 22 matrix keyboard. This fed a small board with some priority encoder chips and other discreet logic to provide 6 analog voltage outputs to steer the PLL chips toward the note you are going to play before you picked the string.
I had an opamp rectifier circuit to provide a voltage (envelope) output for each string. The matrix keyboard and envelope outputs can directly drive a sound chip, but there is no way to track string bends, since the pitch information is not present, so the PLL output is needed.
My next effort will probably use a Teensy board, or several to make a 1V/oct CV for each string, and use that to drive the 1V/oct synth that I am working on now......unless I change my mind again before I get there. The Teensy library does have software freq counting, and FFT, so maybe that's another route. Too soon to tell right now.
Right now, I am trying to pare my wish list of useful "Mini Synth" controls down to 53 knobs, then code them all.
The wiring looks ugly because I did it all in a hurry, but it's really simple. Each pot gets ground and 3 VDC. The wiper from each pot goes to a pin on the micro. Each corresponds to a variable in software with names like VCO1_BLU, so it's rather obvious where it comes from. The left side is all VCO's, and the right is VCA's VCF's and ADSR's, same color coded variables. The big black knob and its 4 little friends on the bottom row are LFO and modulation knobs. I have an Excel spreadsheet to keep track of wire color and pin numbers.
The new megaprocessor board was shipped this afternoon west coast time, and should be in my hands tomorrow.
parasitic ultrsonic oscilation......ugh !!!
Hi guy ......got a hold of a mullard 5-10 amp the other day and thought this would make a good guitar amp.....nice set of transformers , yada yada etc
so a started making a 18 watt tmb.....so far all good....but it seems I have ultrasonic oscilation in the PI.......I come to this conclusion after I disconnected the preamp 12ax7 entirely and attached some music direct to the PI grid .....the sound is almost like blocking distortion but having droped the signal caps and grid stoppers resulted in no change ...dropped a 47pf on PI plates no change
The amp itself without signal is wonderfully Quiet....you can hear white noise as the master fader is brought up.....no squeals or pops of any kind...
would redressing the stage fix it or is there a simpler way...I have not come across this problem before....
Help !!
To add I've made this one before without issues....nice base amp,pedal freindly
Hi guy ......got a hold of a mullard 5-10 amp the other day and thought this would make a good guitar amp.....nice set of transformers , yada yada etc
so a started making a 18 watt tmb.....so far all good....but it seems I have ultrasonic oscilation in the PI.......I come to this conclusion after I disconnected the preamp 12ax7 entirely and attached some music direct to the PI grid .....the sound is almost like blocking distortion but having droped the signal caps and grid stoppers resulted in no change ...dropped a 47pf on PI plates no change
The amp itself without signal is wonderfully Quiet....you can hear white noise as the master fader is brought up.....no squeals or pops of any kind...
would redressing the stage fix it or is there a simpler way...I have not come across this problem before....
Help !!
To add I've made this one before without issues....nice base amp,pedal freindly
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Sherri and I took a little vacation in Florida. I brought the synth prototype and a laptop along for the ride, and found myself sitting on a deserted beach with a laptop watching the sun set and writing code more than once......tough job, but somebody has got to do it.....far cry from the cube farm that I used to work in. The synth with its new high powered processor is slowly coming to life.
This got me thinking about the vacuum tube powered VCF again, but I pushed those thoughts back into the corner of my brain where they belong until I finish something.....I am the king of half finished projects.
Well about a day later the phone rings. My brother on the east coast of Florida wants us to visit him. We are on the west coast. The Google route takes us within 5 miles of ESRC, home of the $1 tube list, so one phone call and $270 brings me to his place tomorrow for a BIG box of tubes. There will be several more tubes to fry, a few more semi - finished budget amps, and maybe a vacuum tube VCF in the cold months to come.......stay tuned.
This got me thinking about the vacuum tube powered VCF again, but I pushed those thoughts back into the corner of my brain where they belong until I finish something.....I am the king of half finished projects.
Well about a day later the phone rings. My brother on the east coast of Florida wants us to visit him. We are on the west coast. The Google route takes us within 5 miles of ESRC, home of the $1 tube list, so one phone call and $270 brings me to his place tomorrow for a BIG box of tubes. There will be several more tubes to fry, a few more semi - finished budget amps, and maybe a vacuum tube VCF in the cold months to come.......stay tuned.
EL86/6CW5 amp design
Hi George,
I have managed to get my PP EL86/6CW5 design to pump out impressive levels of POWER!
My power amp design implements 2 separate power supplies.
I have a regular rather high current capable PT (300mA) supplying a B+ of +280V using 2 6AX4 rectifier tubes, or +315V with jumper sockets to get SS rectification.
I used a cheap $8 Chinese DC-DC boost board for my screens supply.
Following data sheet specs, I provided -18V as my fixed bias level.
Screen voltage at +187V sets my idle current at 47mA per EL86.
The different B+ choices (+280V or +315V) don't seem to have any affect on my idle current setting.
But WOW these little EL86 tubes can pull some current and put out some power. Cranked up and hitting the input hard produces current spikes of 140+mA per tube! And these little Beasts show no signs of Red Plating or even approaching it. I don't know how many Watts of power this little amp is putting out, but I can tell you I think it is louder than many of my PP 6L6 amps.
I've hooked up 2 different pre-amp designs to this Beast.
A Plexi pre-amp I chopped out of my 6V6/6L6 Plexi modified clone.
And another odd tube for guitar amps (6DJ8 totem pole input) pre-amp design.
With the Plexi pre-amp it nearly sounds like an EL34 Plexi!
With the 6DJ8 pre-amp I have a super clean, clear, and articulate tone!
That is until I hit the pre-amp hard, then she growls with unique and pleasing tones to my ears!
I've built what I call my Frankenlab EL86 amp.
It is a platform for trying many different pre-amp/TS designs quickly and efficiently! Eventually I will decide on a simple Head design that has outstanding tone and power that can be built in a small lunchbox style chassis. ;^)
Hi George,
I have managed to get my PP EL86/6CW5 design to pump out impressive levels of POWER!
My power amp design implements 2 separate power supplies.
I have a regular rather high current capable PT (300mA) supplying a B+ of +280V using 2 6AX4 rectifier tubes, or +315V with jumper sockets to get SS rectification.
I used a cheap $8 Chinese DC-DC boost board for my screens supply.
Following data sheet specs, I provided -18V as my fixed bias level.
Screen voltage at +187V sets my idle current at 47mA per EL86.
The different B+ choices (+280V or +315V) don't seem to have any affect on my idle current setting.
But WOW these little EL86 tubes can pull some current and put out some power. Cranked up and hitting the input hard produces current spikes of 140+mA per tube! And these little Beasts show no signs of Red Plating or even approaching it. I don't know how many Watts of power this little amp is putting out, but I can tell you I think it is louder than many of my PP 6L6 amps.
I've hooked up 2 different pre-amp designs to this Beast.
A Plexi pre-amp I chopped out of my 6V6/6L6 Plexi modified clone.
And another odd tube for guitar amps (6DJ8 totem pole input) pre-amp design.
With the Plexi pre-amp it nearly sounds like an EL34 Plexi!
With the 6DJ8 pre-amp I have a super clean, clear, and articulate tone!
That is until I hit the pre-amp hard, then she growls with unique and pleasing tones to my ears!
I've built what I call my Frankenlab EL86 amp.
It is a platform for trying many different pre-amp/TS designs quickly and efficiently! Eventually I will decide on a simple Head design that has outstanding tone and power that can be built in a small lunchbox style chassis. ;^)
I think my OT came from a PP 7868 amp, maybe?
At 4 ohms of speaker load, I have close to the 3K load the tubes want to see.
I have a single input double output connector that I connect 2 8 ohm speaker cabs to.
That powers 4 x 12" 1960's Jensen speakers. It can be loud if it wants to be. ;^)
At 4 ohms of speaker load, I have close to the 3K load the tubes want to see.
I have a single input double output connector that I connect 2 8 ohm speaker cabs to.
That powers 4 x 12" 1960's Jensen speakers. It can be loud if it wants to be. ;^)
Yup, I'm pretty sure my OT came out of a Wurlitzer also.
It's rather large, for little 9 pin tubes, and definitely capable of handling the 25+W these EL86/6CW5s put out in fixed bias mode. Verify the Z of your OT and you will likely need to use a 4 ohm speaker load, like I did, to put these tubes in their Happy Place. ;^)
A slight word of caution.
Since these tubes can conduct extreme amounts of current for a little bottle,
exercise a little more diligence in ensuring proper operating conditions.
They can Red Plate quickly if the bias fails or is set incorrectly.
I have also experienced internal arcing in these tubes.
Big scary volume spikes are the result.
Be ready to hit the power switch quickly if any loud pops occur.
Pops tend to drain the screens voltage supply momentarily.
But multiple arcing events will occur when the screen voltage recovers.
Killing the tube if not halted immediately.
I think I have a few dead Soldiers on my hands now. 8^(
It's OK though, as I had about 18 of them to start with.
I think I've got at least a Dirty Dozen Soldiers still ready for duty. LOL
It's rather large, for little 9 pin tubes, and definitely capable of handling the 25+W these EL86/6CW5s put out in fixed bias mode. Verify the Z of your OT and you will likely need to use a 4 ohm speaker load, like I did, to put these tubes in their Happy Place. ;^)
A slight word of caution.
Since these tubes can conduct extreme amounts of current for a little bottle,
exercise a little more diligence in ensuring proper operating conditions.
They can Red Plate quickly if the bias fails or is set incorrectly.
I have also experienced internal arcing in these tubes.
Big scary volume spikes are the result.
Be ready to hit the power switch quickly if any loud pops occur.
Pops tend to drain the screens voltage supply momentarily.
But multiple arcing events will occur when the screen voltage recovers.
Killing the tube if not halted immediately.
I think I have a few dead Soldiers on my hands now. 8^(
It's OK though, as I had about 18 of them to start with.
I think I've got at least a Dirty Dozen Soldiers still ready for duty. LOL
May I suggest adding grid stoppers to the two triodes in the phase splitter? There really should be a grid stopper for every valve (even if Leo and Jim didn't use them in their classics.)
10k or thereabouts should work, I think.
-Gnobuddy