I don't know what max output voltage of your PC or the input voltage required to drive your active JBL to rated power.
Just like in the analog days you'd have to check the specifications to answer your question.
Art - my Sony MD 7506 headphones sound great. You are right, they are not as loud as the Meze headphones, but they have great sound, and will get plenty of use. Probably will be road headphones.
JJ - my Carvin Mach 100 arrived and this little amp looks great, can't believe they put 100 watts of power into an amp that is about 3" x 5". I used it with my Meze headphones for a quick test, and they sound even louder, and stay clean up to about 50% volume. I don't need it that high, so plenty of headroom. Thank you!
I should have some "wife gone" time tomorrow, so I will play my guitar through the Carvin without horns into my JBL's, will be another good test.
I just ordered some 1/4" to speaker "snap on terminal connectors" so I will be able to test the Carvin with guitar #1 but run them through the horns on guitar #2, that will be a great test, kind of like I used to do before the guitar was built. Then get some REW info and compare to guitar #1 FR output that I already have posted in the YouTube video.
The goal will be to put this amp into the guitar #2 build (if all goes well), just need to cut out a little more wood, plenty of room for a tight mounting, but there may be some creativity with the connectors. Now I just need to find a battery pack that can run this long term, or something similar, and everything can be self contained.
JJ - my Carvin Mach 100 arrived and this little amp looks great, can't believe they put 100 watts of power into an amp that is about 3" x 5". I used it with my Meze headphones for a quick test, and they sound even louder, and stay clean up to about 50% volume. I don't need it that high, so plenty of headroom. Thank you!
I should have some "wife gone" time tomorrow, so I will play my guitar through the Carvin without horns into my JBL's, will be another good test.
I just ordered some 1/4" to speaker "snap on terminal connectors" so I will be able to test the Carvin with guitar #1 but run them through the horns on guitar #2, that will be a great test, kind of like I used to do before the guitar was built. Then get some REW info and compare to guitar #1 FR output that I already have posted in the YouTube video.
The goal will be to put this amp into the guitar #2 build (if all goes well), just need to cut out a little more wood, plenty of room for a tight mounting, but there may be some creativity with the connectors. Now I just need to find a battery pack that can run this long term, or something similar, and everything can be self contained.
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You're welcome. I'm seeing cells of Li-Ion battery within that middle cavity! Careful with how heavy the guitar is getting with all the additional materials inside. Mass is probably good, but up to a point. Remembering my Hagstrom Swede bass, almost to heavy for my back to hold.
As I mentioned previously, there's still a need for some kind of preamp to buffer your pickups, if not add some amp crush 'n color, ambience to your guitar's sound. I'm sure there's dozens of "acoustic" preamps to choose from, also in pedal board format.
As I mentioned previously, there's still a need for some kind of preamp to buffer your pickups, if not add some amp crush 'n color, ambience to your guitar's sound. I'm sure there's dozens of "acoustic" preamps to choose from, also in pedal board format.
Li-Ion battery within that middle cavity indeed! One of the great thing about acoustic guitars is people sit down to play them, so weight is not an issue there, but of course the buskers are a concern, hmm...the pickups are both active and have a preamp, so I think maybe not required, but I am open to ideas, what do you think JJ?
I heard a small piece rolling around inside the Carvin, still there, not sure what it might be, but still works great. This will give me an excuse to take it apart, because I really want to see the 100 watts shoved into the small body!
I heard a small piece rolling around inside the Carvin, still there, not sure what it might be, but still works great. This will give me an excuse to take it apart, because I really want to see the 100 watts shoved into the small body!
Well, maybe they drive the Carvin just fine through a volume pot, which could be an extension on the one atop the Carvin. My Yamaha's top mounted controls are volume and balance, between the mag and piezo pickup. Could be that simple.
But then how to handle the necessary "tone" control. Usually on a guitar you get treble-cut; said Yamaha has a "graphic EQ" on the top edge mounted preamp part for tone. Unsure if yours sports such an arrangement.
Then in my mind anyway, all amplified instruments should have the option of some dynamic compression. Especially for an instrument so applicable to busking, where you definitely need to raise your average sound level above the din. Its a rarely offered feature, but I think would make your instrument stand out in such an application.
Did anybody see this? WOW! These guys have huge melons. I can only imagine what it was like to run a business for 10 years with no profits. They stick it out and likely did well after that, they have great products today, not sure how long it took get there. Then they hit the jackpot, God bless them!
JJ - everything with the Carvin looked good, started up with the Mag pickup only, sounded good, but not much power. Then I kicked in the piezo pickup, and power like crazy, 100 watts you are not kidding, but the tone was just awful, even at much lower levels. Not sure what is going on with all these small amps, but they always have horrible tone. Made for electric guitar? Maybe they shred there, but with an acoustic guitar, no dice. Thanks for the recommendation brother, really thought we had something.
Quaky sound, yeah I guess, but it also sounded like I was playing through a tin can, just terrible, almost zero lows, and zero warm sound. I do not understand it! Thoughts? I switched back to my Roland and all the great sound is back. I am very grateful for the sound I have now, but I do not mind testing other options, you never know!
Quaky sound, yeah I guess, but it also sounded like I was playing through a tin can, just terrible, almost zero lows, and zero warm sound. I do not understand it! Thoughts? I switched back to my Roland and all the great sound is back. I am very grateful for the sound I have now, but I do not mind testing other options, you never know!
I'll guess that this pedal-amp was designed to be driven by a "line" input, that is, the buffered output (low Z) of some upstream device.
If your Roland amp has an effects loop, you can take the "send" from that and connect it to this amp. That way the Roland will "buffer" your pickups, while this amp will power the speakers. Or get a "acoustic guitar preamp" and place it between your guitar and this amp.
Maybe you're still within the window of being able to send it back? I understand your pickups are buffered, but like yourself, dont understand the results you're getting. Do just the tone control circuits in the Roland do that much?
If your Roland amp has an effects loop, you can take the "send" from that and connect it to this amp. That way the Roland will "buffer" your pickups, while this amp will power the speakers. Or get a "acoustic guitar preamp" and place it between your guitar and this amp.
Maybe you're still within the window of being able to send it back? I understand your pickups are buffered, but like yourself, dont understand the results you're getting. Do just the tone control circuits in the Roland do that much?
Your picture of the amp's connection shows no speaker cover, which could reduce bass and change the response compared to a sealed back chamber.
Try swapping the spade lugs on one driver.
That description sounds like the result of drivers wired with reverse polarity.
Try swapping the spade lugs on one driver.
Thanks Art - I will check the polarity. The speakers are covered at the front of the drivers of course, and always uncovered at the back of the drivers. I like to feel the sound in my body when I play, and it sounds and measures great this way. For this Carvin setup I will cover them front and back and and see what happens.
JJ- I am not giving up on this amp, still really like the small package and big power that I really need in this application. The Roland does have an effects loop, so I will try your suggestion. I rarely use the tone controls on the Roland, just have them all at zero, very happy with that setup. I do test them at times, and they do not change that sound that much really, thank you gents, stay tuned!
JJ- I am not giving up on this amp, still really like the small package and big power that I really need in this application. The Roland does have an effects loop, so I will try your suggestion. I rarely use the tone controls on the Roland, just have them all at zero, very happy with that setup. I do test them at times, and they do not change that sound that much really, thank you gents, stay tuned!
As I'm sure I've noted before, the open to the air chamber at the speaker backs wont do much for the power handling of your horn system.
This is because the drivers need an air volume to push against which serves as a sort of compressible spring. Wide open they're just flapping about and as such will get destroyed mechanically before the voice coils burn up under high power. And I'm sure no customer would ever play using the full 50W into each of those little drivers.
There's many things you could experiment with besides just leaving that chamber open. There's another chamber whose volume this chamber could be connected to. There's a structure called a resistive port, that would allow some sound out the back of the guitar to your liking. There's a reflex port, a slot or a tube that could be located at the speaker chamber or up in the next chamber, if connected.
Before you take it to Berklee (Hoping you're invited) do some work around different ways you can address this. It's not an open baffle speaker, really.
I hear you JJ, when I play the guitar, the back of the drivers are covered by my body, so I can feel the music, pretty cool. That said I know it is not a 100% seal, but is measures pretty close from memory of results way back. Totally open I agree would be a problem. Plus it will look much better sealed, so If I get a decent demo going, I will likely seal it with wood. Plus I like your idea regarding chamber/porting, something to think about for sure!
Here's a patent for ya! You could suspend the "cover" with a edge boundary of butyl rubber. Make the cover itself stiff using bracing. Arrange it so it can displace freely - without knocking into anything within the cavity, like the speaker magnets. That'll be better for the speaker drivers than "WFO", but still allow you to "feel the vibes" with your body coming from the back of the guitar.
I dont know of any guitar that deliberately introduces an electronically driven plate as part of the back surface, allowing the player to "feel" the sound of what they're playing tactically. Given there's a deaf audio fellow who listens with his hands resting upon a balloon - and can tell the difference between line level cables - I've no doubt a tactile listening transducer would work to allow a deaf person to play acoustic guitar.
I dont know of any guitar that deliberately introduces an electronically driven plate as part of the back surface, allowing the player to "feel" the sound of what they're playing tactically. Given there's a deaf audio fellow who listens with his hands resting upon a balloon - and can tell the difference between line level cables - I've no doubt a tactile listening transducer would work to allow a deaf person to play acoustic guitar.
JJ - I like that idea! I am definitely going to clean up the back of the guitar for a more professional presentation, but I do like the open chamber, as long as my body covers it to work well. The seal not being 100% is still a concern, will experiment with this, per your suggestion. Plus I will do the polarity swap for the Carvin.
It has been a month since the Berklee possibility, so will contact him this weekend. Plus I will send to other music department professors at large universities, why not try?
For guitar #2 I have the dovetail neck fit to the body, great fit, straight, straight, straight. I am thinking of going back to Ian at Chicago School of Guitar Making for some solo class time regarding staining, polyurethane finish, polishing, bindings, other finishing touches to make this one not only sound great, but hopefully look great also. Maybe some soundboard screw options? 🤣
It has been a month since the Berklee possibility, so will contact him this weekend. Plus I will send to other music department professors at large universities, why not try?
For guitar #2 I have the dovetail neck fit to the body, great fit, straight, straight, straight. I am thinking of going back to Ian at Chicago School of Guitar Making for some solo class time regarding staining, polyurethane finish, polishing, bindings, other finishing touches to make this one not only sound great, but hopefully look great also. Maybe some soundboard screw options? 🤣
https://drive.google.com/file/d/1B_l0oouoINPuiOxNpbbJKd--4RYQvFmb/view?usp=sharing
YouTube video attached again, a few thoughts from my end, comments welcome!
I hope these specific times in the video show what I am trying to achieve:
4:17 Rich Lows
4:26 Beautiful Highs
4:48 Lows and Highs
6:32 Harmonic Power and Sustain
Note: Mids are strong everywhere, I hope.
7:28 Sparkle
9:16 Resonance and Sustain
11:15 Great Tone
11:36 Great Power
12:00 FUN!
YouTube video attached again, a few thoughts from my end, comments welcome!
I hope these specific times in the video show what I am trying to achieve:
4:17 Rich Lows
4:26 Beautiful Highs
4:48 Lows and Highs
6:32 Harmonic Power and Sustain
Note: Mids are strong everywhere, I hope.
7:28 Sparkle
9:16 Resonance and Sustain
11:15 Great Tone
11:36 Great Power
12:00 FUN!
Ok I tried the Carvin again with standard hookups, same result of course. Then I tried reverse polarity on one speaker only, and pretty much the same result. The mag pickup by itself sounded pretty good, but still major lack of power. Then I added the piezo and BAM, way more power, but still sounded like ****!
It did not sound as much like a tin can, but man I finally heard the piezo quacky sound that I never understood before. It was quacking like a duck! And the louder I made it, the worse it sounded, just terrible. I still think it is a very cool small and powerful amp, but just for an electric guitar.
Oh well, a good test. No such thing as a bad test, you always learn something! I am going back to my Roland, drivers and horns now, love that sound and will jam for two hours tonight.
I finally grew the melons' to ask the Berklee Professor how his students and colleagues liked my guitar, just a few hours ago. Maybe I will get some good news, and maybe I will get shafted, we shall see, stay tuned! 😎
It did not sound as much like a tin can, but man I finally heard the piezo quacky sound that I never understood before. It was quacking like a duck! And the louder I made it, the worse it sounded, just terrible. I still think it is a very cool small and powerful amp, but just for an electric guitar.
Oh well, a good test. No such thing as a bad test, you always learn something! I am going back to my Roland, drivers and horns now, love that sound and will jam for two hours tonight.
I finally grew the melons' to ask the Berklee Professor how his students and colleagues liked my guitar, just a few hours ago. Maybe I will get some good news, and maybe I will get shafted, we shall see, stay tuned! 😎
Something is wrong if reversing the polarity of one speaker results in "pretty much the same result", there should be either an increase or reduction of the low end.
If you are sending one pickup right and the other left, reversing speaker polarity may not have much effect.
Have you verified both amp sides and speakers are working?
The Carvin has no pre-amp. What are you using as a pre-amp and mixer to get both pickups through both speakers?
Good timing Art, was just about to post a somewhat different question for you. I should say pretty much the same for the mag pickup only, that is what I tried first, and for some reason it is really under powered, so I am likely not hearing what is happening, and I did not measure anything last night, to busy jamming and drinking beer. 🤣
I did verify both amp sides and speakers are working, and yes for this amp only, one pickup is going to a speaker, and the other pickup to the other speaker. Both pickups have a preamp, so that is all I ever use for my preamp.
For whatever reason the piezo has much more power with this amp (not true for my usual Roland). So when I say the piezo sounded very very quaky, that could be a result of the low end being reduced and I hear much more high quaky end? I am not giving up on this amp, I just love the power and size, I will keep trying.
I did verify both amp sides and speakers are working, and yes for this amp only, one pickup is going to a speaker, and the other pickup to the other speaker. Both pickups have a preamp, so that is all I ever use for my preamp.
For whatever reason the piezo has much more power with this amp (not true for my usual Roland). So when I say the piezo sounded very very quaky, that could be a result of the low end being reduced and I hear much more high quaky end? I am not giving up on this amp, I just love the power and size, I will keep trying.
Art - so what gives with the "reverse horn" supposedly lowering the lowest note? The Bose Waveguide Radio is like this. The iPhone measurement to the left measures good lows/mids and sounds like good lows/mids, measured directly in front of the Bose at one meter distance. I heard and also measure the highs taking a nosedive at 8k. There was a lack of my dreaded "tinny tone" but there was not any sparkle either. This was a Bonnie Raitt song, so plenty of great talent.
When I note Casey is playing with plenty of sparkle on my YouTube video at 7:28 time frame, you can sure hear it, and the harmonics at 4k, 8k and above measure very strong.
So the question is: does a "reverse horn" really increase the lows, and then also kill the harmonics above about 8k? If they do, why would you use it? Two out of three just does not cut it, as we all know. Thoughts? Thanks Art!
When I note Casey is playing with plenty of sparkle on my YouTube video at 7:28 time frame, you can sure hear it, and the harmonics at 4k, 8k and above measure very strong.
So the question is: does a "reverse horn" really increase the lows, and then also kill the harmonics above about 8k? If they do, why would you use it? Two out of three just does not cut it, as we all know. Thoughts? Thanks Art!
Do the effects send experiment from your Roland? That should allow you to work with the Carvin, but get the Roland's "benefit" to the pickups. It "should" eliminate any issue using the pickups directly to the Carvin. Result would determine next step.