Guitar Cabinet / Amp

[JMFahey]

... But then you've got the chosen colouration from the amp modeller, and you're putting it through something that will always add it's own "tone" to those settings, which might be good for one sound, but might not work for another.

Isn't it better to have a flat speaker?

There's also the point that the flat speaker would be able to add reverb effects that sound like the amp is in a hall/room/whatever, whereas the guitar speaker will make the reverb sound coloured, too.

Chris

Don't overthink it

Short answer: Tech 21, having invented among other things the SansAmp ... which include speaker simulators, even "mic position simulators" .... uses a Guitar speaker (and a Celestion none the less) instead of a flat speaker such as, say, an Eminence Beta series or similar.
That alone speaks volumes.

Slightly longer: you WILL need that around 10dB peak in the 2500 to 3500Hz area, and you can NOT simulate Acoustic Efficiency.

If you want to do it "all in Software" you will need 10dB extra power, just for that. Do the Math.

Even worse, typical flat speakers are 3 to 4 dB less efficient than Guitar speakers, add that to the increased power demand.

In a nutshell: it´s way better, in practice, to start with a Guitar speaker which is LOUD and is already in the ballpark, and simply stop creating the 10dB peak in software.

Same result with normal power demands instead of impossible ones.

 

[Gnobuddy]

"Loud" is a different concept when it comes to live music - if you've got a loud drummer, things can escalate very quickly.
Chris

Agreed (been there, have the earplugs to prove it!) But from post #3, I got the impression the OP was intending to use this at home by himself. I could be wrong, though.

There is lots of music to be made without the many headaches of dealing with live acoustic drums, which IMO are simply no longer suited to many music-making venues and situations in these days of crowded urban living and low tolerance for live music.

Over previous centuries, the military evolved ancient and relatively quiet folk drums into super-loud monsters designed to keep long columns of soldiers marching in lock-step in the great outdoors. Modern rock drum kits came from that evolutionary history, and now they are dinosaurs, too loud, too big, and too inconvenient for the world most of us live in today.

I play weekly with a group of friends. We have no drummer, though we just recently got a cajon. When not playing or singing or thumping on the cajon, I sometimes use a little plastic shaker to add a little percussion. At home, I sometimes use Hydrogen (software drum machine for Linux), or put together a little loop of bass, chords, and drums in Musescore (music notation program), or pull out the Trio+ pedal and let it come up with bass and drums to play along with.

The common factor is that the "drums" don't need to be any louder than an acoustic guitar. What these solutions lack in sheer visceral impact, they more than make up for in versatility and day-to-day usability.

-Gnobuddy

 

[THRobinson]

Agreed (been there, have the earplugs to prove it!) But from post #3, I got the impression the OP was intending to use this at home by himself. I could be wrong, though.

I can't play worth a s#@t... haven't played in 22yrs, just starting to back into it again. I missed building and fixing guitars more than playing, and since I like DIY stuff, figured I'd make myself a powered speaker. I got a laptop with GuitarRig on it so rather than buy an amp where reviews say good clean poor distortion, or good distortion poor clean, or decent amp crappy speakers, etc... just make a powered speaker and model with the software.

Seems in my price range, amps new or used, always seem to be half good and half bad, and most recommend buying a new speaker anyways.

Though... was eyeing up a used VOX VT20+ thinking gut it and make a new box for it. Seen a lot of reviews saying through a 212 cab it sounds great. Been keeping an eye open for a red-stripe Bandit/Studio 112, or a Valveking. Was about to buy one used, then the guy kept putting off a day/time, then changed his mind. :S

 

[Gnobuddy]

...just starting to back into it again.

Cool, you get to enjoy the early steep part of the learning curve, where you can hear yourself improve from day to day.

I got a laptop with GuitarRig on it so rather than buy an amp...

You are in the perfect situation to slap together a low cost, quick-n-dirty, solution that will get you playing and having fun immediately, while you ponder the perfect setup you're going to build eventually.

The attached pics show you what I put together recently with mostly thrift-store-refugee parts. It started with a pair of Sony speakers for $3.99, and a Kodak 24 volt 1.8 amp switch-mode power supply for another $3.99. Add a cheap class-D power amp board, a home-made 1/4" jack to RCA plug adaptor, and a Joyo American Sound or Joyo British Sound pedal (both had been sitting in my closet for years.) Voila, instant home practice guitar amp!

This one will get a little additional development. The power supply has now been replaced by a battery pack for outdoor fun in a park, and I plan to add an XLR jack or two for microphone inputs soon. But it is usable now - I was noodling around on it just last night.

Those Joyo pedals are Sansamp-alikes, i.e. fully analogue guitar amp emulators, which include some sort of speaker-emulation filter built in. The American Sound tries to mimic Fenders from the tweed and blackface era; the British Sound tries to be more like a Marshall.

-Gnobuddy

 

[THRobinson]

Wow...came back to reread something and didn't realize I missed about 6 messages.

Cool, you get to enjoy the early steep part of the learning curve, where you can hear yourself improve from day to day.

Ha, I'm more a pessimist. I see it as the annoying re-learning curve where I think to myself, wow, I kinda wasted a lot of money on guitar lessons back in highschool, since I don't remember anything at all.

Though, if sitting watching TV and just playing around, if not paying attention I'll sometimes find myself playing something I forgot all about. Weird how memory works that way.

But ya, going back a bit... 90+watts is a bit much. Though if I finish fixing the garage (100yr old small barn, needs lots of work) I'd probably have the amp out there for music in the summer and testing guitars out on so, primarily in-house no band so 20-30w be plenty, but, in the garage would like more power and small chance nephew may borrow it if any good in which case may need more power as well.

I have currently a free amp, a Crate GX-15. It is what it is... not bad, not impressive by any means.

Though got me thinking of a cheap amp and swapping guts. Seen a few amps online where they say on it's own, not great, through 2x12 cab it's a great amp (ie. the Vox I mentioned). Get a pair of 8ohm 12" speakers in parallel to make them 4ohm (think I got that right).

Few sites online even where you can get the diamond grill cloth and tolex, can build an amp to look identical to a VOX's style but totally new.

 

[dotneck335]

........Those Joyo pedals are Sansamp-alikes, i.e. fully analogue guitar amp emulators, which include some sort of speaker-emulation filter built in. The American Sound tries to mimic Fenders from the tweed and blackface era; the British Sound tries to be more like a Marshall.
-Gnobuddy

How does the Joyo compare to the COSM emulator(s) that are in the Roland MicroCube??

 

[Gnobuddy]

How does the Joyo compare to the COSM emulator(s) that are in the Roland MicroCube??

I may not be the right person to ask - I really don't like the sound of the little box, little speaker, and drastic lack of bass in the MicroCube, and I haven't heard a MicroCube connected to a better external speaker and cab.

I do like the Joyos, especially the American Sound. For what it's worth, I have tried and been very disappointed by a number of digital modelling amps and preamps, including several Line 6, Digitech, and Zoom (but no Boss) products. To me, all of them sounded gritty or harsh, lacked the singing shimmery cleans you get from an actual Blackface Fender, and caused me severe ear-fatigue after a few minutes.

Then I heard about the Joyo American Sound, found a few You Tube video demos, and liked the demos enough to get three different Joyo's - American Sound, British Sound, AC Tone - to try. (The cost of all three pedals added up to only about $100 USD at the time.)

For me, the Joyo American Sound was the best solid-state tube amp emulation I had ever heard up till that point in time. (Since then I've heard You Tube demos of great sounding digital modellers like the Atomic Amplifire - which cost more than I would spend to design and build several real tube amps. No thanks.)

The companion Joyo British Sound and Joyo AC Tone sounded pretty good, without the harshness and ear-fatigue that the digital pedals tended to have, but I didn't use them as much, purely because of my musical tastes.

This thread inspired me to dig the Joyos out of the closet, and I have been experimenting with them for the last week or two. At last night's jam, I used a Danelectro 7-band graphic EQ, the Joyo American Sound, a delay, and a reverb pedal, going straight into my little P.A.

With a little tinkering with EQ, I got a nice clean sound with the Joyo switched out of the loop, and a very usable range of sounds for single-note solos with the American Sound turned on. Once I set the "Drive" knob carefully, I could go from slight crunch to 5E3-like throatiness to bright and clean, just by varying my touch on the guitar. IMO the range of touch-sensitivity is not as good as a real tube amp, but better than any of the digital modellers I've tried.

One of the noticeable things about the American Sound is that my guitar still sounds like my guitar through it (unlike the Line 6 stuff that sounds like the same kazoo whatever guitar you plug into it.) Last night I was using a thin semi-hollow Agile electric guitar closely inspired by Gibson's masterpiece, the ES-335.

Comparing digital amp modellers to analog ones like the Sansamp and Joyo, the obvious difference is that the Joyos are more or less one-trick ponies. You can't get the Fenderish Joyo to sound much like a VOX, for instance. Personally, though, I would rather get two or three good sounds out of a pedal than the 50 different flavours of kazoo offered by Line 6 et al.

Speaking of Sansamp, I've read claims that these Joyo pedals are closely modelled after similar Sansamp products (the Tech21 Character series.) I haven't attempted to verify those claims, and I've never played through a real (pricey) Sansamp.

I don't know if that was helpful or not...but there are plenty of demo videos of these Joyo amp-emulator pedals on You Tube, including some with excellent sound quality (such as the infamous one by "intheblues" where he compares a real Deluxe Reverb to a Joyo American Sound and asked the viewer to identify which was which.)

-Gnobuddy

 

[dotneck335]

...... Gibson's masterpiece, the ES-335.
I don't know if that was helpful or not...but there are plenty of demo videos of these Joyo amp-emulator pedals on You Tube, including some with excellent sound quality (such as the infamous one by "intheblues" where he compares a real Deluxe Reverb to a Joyo American Sound and asked the viewer to identify which was which.) -Gnobuddy

Yeah, I saw that also. Did he ever identify which was which? I'm not sure which was the real tube amp, either, but I liked the sound of 'B' better. Which did you like?

 

[THRobinson]

Still sorting out what to get and what will work for this project.

Think I've gotten it narrowed down. Because of price, to get an amp that will take a 32-34v PSU, and cost of the PSU itself... I may get a 4ohm speaker instead and a 24v PSU which seems much cheaper and more common, and a 100w mono amp, which max psu is 24v which may be pushing it a bit? Maybe a regulator and drop to 22v?

Still unclear how to attach the pre-amp, power wise... it's 12-35v so within range, do I just split the power coming from the psu and run a pair of wires to the amp and a pair to the pre-amp?

Next jump up I think is the 200w amp, maxes at 36v. Then the 8ohm speaker will be ok, get a 32v5a PSU. But price of the amp and the psu both jump up.

If I go 8ohm I'll probably get that Eminence Beta, otherwise, 4ohm I'd go back to the warehouse Reaper.

Amps
http://store3.sure-electronics.com/1-x-100-watt-class-d-audio-amplifier-board-tpa3116
http://store3.sure-electronics.com/1-x-200-watt-class-d-audio-amplifier-board-t-amp

Speakers
https://nextgenguitars.ca/products/eminence-beta-12lta-225w-8ohm.html
(4ohm version available not listed) https://nextgenguitars.ca/products/wgs-12-reaper-hp-50w-8ohm.html

PSU
https://www.ebay.ca/itm/32V-5A-160W...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649
https://www.ebay.ca/itm/AC-110-220V...var=552668892820&_trksid=p2060353.m1438.l2649

Preamp
https://www.ebay.ca/itm/12-35V-NE55...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649
(no mention of voltage) https://www.ebay.ca/itm/Amplifier-P...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

Hoping, all these are good options? Just need to choose 24v or 32v, which will determine amp and speaker ohms.

Look good?

 

[Printer2]

The Beta is a woofer, might be a little light in the top end. The only other 4 ohm they have is the Texas Heat


https://nextgenguitars.ca/products/eminence-texas-heat/

 

[Gnobuddy]

Did he ever identify which was which?

He did, I think it's in one of his posts well down the page.

I'm not sure which was the real tube amp, either, but I liked the sound of 'B' better. Which did you like?

Good ear! You picked the real tube amp.

I heard little bursts of harsh clipping from "A" early on in the first clip, each time the player applied right-hand palm muting, which immediately made me think that was the Joyo. "B" didn't display the same sonic uglies, just a quiet "thump" each time the right hand palm muting occurred.

At about 1:47 into the clip, there are some slow picked arpeggios, and once again, "A" produces little bursts of harshness with each note. The same arpeggios are played through "B" immediately afterward, and there is no harshness at all.

That sort of harsh / gritty clipping is one of the things I really dislike in solid-state amps and guitar pedals. I was pretty sure by then that "A" was the Joyo, and "B" the real tube amp. It turns out I was right, as were many of the other people who posted to the thread. Your ears picked the tube amp, as well.

IMO the Joyo American Sound is better fake butter than any of the other tube amp emulation pedals I've heard, but evidently, both you and I can indeed "believe it's not butter". It's close, but with audible flaws.

Still - when a $30 solid-state pedal actually sounds pretty close to a $1500 tube amp, that's very impressive in my book. And when the real tube amp is not an option for whatever reason (like your portable Princeton), the Joyo makes a pretty acceptable second-best IMO.

-Gnobuddy

 

[Gnobuddy]

Still unclear how to attach the pre-amp, power wise... it's 12-35v so within range, do I just split the power coming from the psu and run a pair of wires to the amp and a pair to the pre-amp?

I suggest putting a resistor in series (say 1k), and an electrolytic filter cap across the preamp supply rails (say 100 uF.). The cap should be rated for the full DC voltage with a little safety margin, so 35V minimum, 50V better.

You can solder a 0.1 uF ceramic cap (again, rated 35V or more) across the preamp power supply rails as well. At very high frequencies, electrolytic caps don't behave well, and the little ceramic cap will take over and keep things stable all the way up into the radio frequency band. (Modern solid-state circuits like these are quite capable of oscillating at radio frequencies, so keeping them stable up there is quite a good idea.)

This forms a simple RC filter that will help to keep things stable - otherwise the power amp creates fluctuations in the DC supply voltage that leak back into the preamp, and may cause oscillation, howling, whistling, motor-boating, etc.

Just need to choose 24v or 32v, which will determine amp and speaker ohms.

Exactly!

I found cheap stereo class-D power amp boards all over Amazon.ca, and few mono boards. I did some of my benchtop prototyping using only one speaker hooked to only one channel, with an 8 ohm, 10 W resistor wired to the second channel as a dummy load, just to make sure it was stable and happy.

-Gnobuddy

 

[THRobinson]

I'll look elsewhere for sure... not sure why I keep going for those SURE boards apart from looking well made. Seen some on eBay cheaper, but look sloppily made.

Maybe, to keep from being to close to the max power allowed (and forgot about that 10% distorion vs 1%) ... I should go for the 4ohm speaker, 24v 5a power supply, and the 200w amp. 150W@3Ω 34V DC THD+N 1%... so a 4ohm speaker is more than 3ohm, and 24v less than 34v so no worries about the clipping/distortion, min. PSU allowed says 15v so, bigger than that as well.

From the chart back on pg3 (?) at 4ohm 24v would be around 55w... so to be safe I guess find a 75w speaker. The Reaper was recommended by Warehouse but only 50w. Eminence BETA's are 8ohm only it seems. Could always go 2x12 I guess but that's a pricey solution to getting 4ohm.

 

[Gnobuddy]

Seen some on eBay cheaper, but look sloppily made.

Agree, some look pretty sloppy, and the Sure stuff does look like they use tighter quality control.

I'm using one of these: https://www.amazon.ca/Yeeco-Channel...5?s=electronics&ie=UTF8&qid=1528402069&sr=1-5

Though the ad copy says "DC 15 - 34V", I found 32V filter caps on the board. I'm running it with either a 24V power supply, or a nominally 20 volt battery pack for off-grid use.

From the chart back on pg3 (?) at 4ohm 24v would be around 55w... so to be safe I guess find a 75w speaker. The Reaper was recommended by Warehouse but only 50w.

You could always drop the supply voltage...or settle for around 30 watts RMS, which you can get with either a 24 V power supply and 8 ohm speaker, or an 18 V power supply and 4 ohm speaker.

Could always go 2x12 I guess but that's a pricey solution to getting 4ohm.

Yeah, guitar speakers have priced themselves into the stratosphere. It seems a bit silly when an aftermarket guitar speaker by itself costs as much as an entire Craigslist (solid state) guitar amp!

If you haunt the classified ads long enough, you may get lucky and turn up an affordable pair of vintage organ speakers that work well for guitar (because back then they were all the same kind of speaker.) They will not be 4 ohms, and watch out for 16 ohm speakers, otherwise you will be back in the 8-ohm boat even with two in parallel!


Then again, vintage speakers with old dried-out glue and old dried-out paper cones probably won't cope with the high power levels you're considering.


-Gnobuddy

 

[Printer2]

I do like the Joyos, especially the American Sound.

Any idea what they have for a circuit in there?

 

[Gnobuddy]

Any idea what they have for a circuit in there?

I never made an attempt to work out the schematic of my Joyo pedals, but apparently these are variants of the Sansamp / Tech21 "Character Series" pedals.

You've probably seen the Sansamp schematic floating around - I think it's been around since the 1980s, and has a slew of op-amps in it, including a few TLC272 (all-MOSFET) amps whose output can go rail-to-rail within a few millivolts.

I do not understand how the Sansamp circuit - which looks like it should produce lots of hard clipping - actually produces fairly "tubey" sounds, and in fact, does that better than just about anything else out there except real tubes, and the newest and most expensive flavours of software / hardware digital amp modellers.

-Gnobuddy

 

[JMFahey]

I never made an attempt to work out the schematic of my Joyo pedals, but apparently these are variants of the Sansamp / Tech21 "Character Series" pedals.

You've probably seen the Sansamp schematic floating around - I think it's been around since the 1980s, and has a slew of op-amps in it, including a few TLC272 (all-MOSFET) amps whose output can go rail-to-rail within a few millivolts.

I do not understand how the Sansamp circuit - which looks like it should produce lots of hard clipping - actually produces fairly "tubey" sounds, and in fact, does that better than just about anything else out there except real tubes, and the newest and most expensive flavours of software / hardware digital amp modellers.

-Gnobuddy

because its Designer, Andrew Barta, knows his sh*t.
Nothing more, nothing less.
From: https://www.bassplayer.com/gear/tech-voices-tech-21s-andrew-barta

LONG BEFORE THE DIGITAL-MODELING REVOLUTION, Tech 21 pioneered a powerful and musical means of emulating the distinctive distortion characteristics, frequency curve, and responsiveness of tube amps with the all-analog SansAmp. The revolutionary pedal was a new means of achieving rich and colorful tube-like tone without the expense, heft, and maintenance headaches of the real deal. ........
I would say tubes have a warm sound. Obviously this is not a technical term; it’s subjective. The reality is that the warmth is coming not from the heat of the tubes, but from their imperfections, as they are not 100% linear. Tubes generate overtones and harmonics on top of the input signal. As they are pushed further and further, you get more and more of this effect. ........
Solid-state devices are designed to be “perfect.” When they reach the limit of their linear operation, the distortion can quickly become harsh. My goal was to emulate the sonic imperfections of tube devices, but with consistent performance. Once I had something tangible, back in 1987, I tried to shop the technology around to some of the major manufacturers. It took two years of hearing “thanks, but no thanks” until I gave up and started the company. So in 1989, the SansAmp was introduced .....

 

[Printer2]

I hear that it might be a Tech 21 ripoff but without any confirmation on the guitar forums who knows?

 

[THRobinson]

I'm using one of these: https://www.amazon.ca/Yeeco-Channel-...8402069&sr=1-5

Weird... listed as mono-amp but then says 2x100W. I guess next question is, how did you know which cap was a filter cap?

For the most part, 200w range, the other amp I see posted a lot is this one, but, doesn't seem to have the same level of detail (specs wise) as the Sure ones have. 10%/1% info, max PSU, etc...

AMAZON 200w Mono

I think I'll probably go with that Sure 1x200w amp... then won't matter if I go 4Ohm or 8Ohm speaker. Then whichever speaker I use I match to either a 24v or 34v PSU. I could go lower wattage... but for whatever reason, I got my heart set on 50w. I think just futureproofing really... again, my nephew plays and may wanna borrow it sometimes and if drums involved, depending where playing, the 50w may be needed.

Oh, now I get to play around with Google Sketchup and design a box for it. So far I'm torn between vintage tweed look, black VOX style, or I keep leaning towards that brown western tolex and brown/black basketweave grill cloth.

Box wise... also debating open back, closed, or closed back with ports in the front.

But guess I just need to decide 24v or 34v... the rest I think I have sorted (thanks to you guys).

Posted in a couple of guitar forums as well, asking for recommended 12" speakers for a modelling amp but got zilch for a response.

Only other detail to sort out is powering the preamp... and which one. some have a volume knob already... some have dual-tubes. I am a tube fan-boy... but for this amp I think being modelling, I'll go solid state.

 

[Gnobuddy]

Weird... listed as mono-amp but then says 2x100W.

If you mouse over those little rectangles, each one pops up an ad for a different amp sold by the same company. The one that is highlighted with a thin red border is the one currently being displayed on the page - and it's stereo.

I guess next question is, how did you know which cap was a filter cap?

Look for the PCB traces its soldered to. Power and ground? It needs to be rated for the full power supply voltage, plus a safety margin of at least 10%, preferably more.

For the most part, 200w range, the other amp I see posted a lot is this one, but, doesn't seem to have the same level of detail (specs wise) as the Sure ones have. 10%/1% info, max PSU, etc...

All the clever bits are inside the actual IC (chip), and the chip manufacturer usually publishes a reference PCB layout and schematic. Many (most?) of these boards we see are going to be direct copies of that manufacturer supplied reference design, maybe with minor tweaks such as adding a volume control or input connector.



This is fast-food electronic design: we don't know too much about what's inside that hamburger, but we know one will be very much like the next. Same thing with these amps - barring a catastrophically stupid mistake, they will all work, distortion will be below what the human ear can detect until clipping starts, and power outputs will be determined by power supply voltage and speaker impedance, not by the specific chip or the company that plugged the parts into the PCB.

Oh, now I get to play around with Google Sketchup and design a box for it. So far I'm torn between vintage tweed look, black VOX style, or I keep leaning towards that brown western tolex and brown/black basketweave grill cloth.

Or just do your own thing...


The pics are of an amp I built recently to give a friend. The grille-cloth is a dollar-store place mat. I built the cab from knotty pine.


The grille is actually quite opaque in real life, it's just the camera flash that lets you see the plywood behind it. That wood is completely invisible under normal circumstances.


The letters "DF" are my friends initials.



-Gnobuddy