Many years ago I bought a BYOB (Build Your Own Buitar) from Hobby Lobby and got it together a few years ago. As a non-musician I have since decided that maybe I could eventually learn to play a frew notes on a bass guitar so I bought a Harley David ... Bentley P-bass kit from the German shop Thomann.
Whilst making work on the body (I will borrow a jig saw for the headstock - my design), I have started looking for a amp/speaker combo. Luckily, with workers replacing the old roofs, and throwing away plywood offcuts, I have enough material for a box to hold that one. It's not furniture grade, but still 15mm pretty acceptable plywood (often referred to as "plyfa" in Swedish). (All dimension in normal units (centigrade).
The guitar is the Harley Benton P-bass as it looks nicer and I just found a heavy coaxial speaker from Master Audio (Italy), an CSX08, an 8", 4.5kg piece with what looks like a small horn tweeter. Stated freqency range 63Hz - 20kHz (could be lower) and recommended crossover frequency of 1.7kHz. 6dB/12dB crossover.
I had an idea to go for a speaker box of approx 400 x 500 x 250mm (16" x 20" x 10") or slightly smaller, using a sort of Onken design or maybe just a single slit, but nothing decided yet.
When it comes to an amp, there's an "issue". I am not going to play at Stockwood ... errr ... Woodstock, but at home and, if I learn more that one note at local events in our old folks club and I think 50W amperage will be enuff.
I've gotten a pair of simple 50W transistor amps built from cheap Chian kits and I guess one of these would be perfect. Else a similar kit from EliExpress is considered: THIS ONE.
For testing I have gotten a D-class chipamp, which had been nice as it doesn't requires a lot of space heatsinks and whatnot. A simple SMPS will do fine (it it works).
I love to fiddle with things and make things a bit diffrunt. I've got 50 shades of pink .. 2 actually for the bass and I will try to mix them in some "odd way". Also gotten a green pickguard that will match the pink body perfectly
.
The speaker/amp combo will be covered in vinyl (black-ish) and apart from thinking of power amplifier, I must look up a decent preamp.
This is my plan and I am open for suggestions ... open for REASONABLE suggestions
, remember that this is a mid- to lowfi project. For fun. Low cost.
Whilst making work on the body (I will borrow a jig saw for the headstock - my design), I have started looking for a amp/speaker combo. Luckily, with workers replacing the old roofs, and throwing away plywood offcuts, I have enough material for a box to hold that one. It's not furniture grade, but still 15mm pretty acceptable plywood (often referred to as "plyfa" in Swedish). (All dimension in normal units (centigrade).
The guitar is the Harley Benton P-bass as it looks nicer and I just found a heavy coaxial speaker from Master Audio (Italy), an CSX08, an 8", 4.5kg piece with what looks like a small horn tweeter. Stated freqency range 63Hz - 20kHz (could be lower) and recommended crossover frequency of 1.7kHz. 6dB/12dB crossover.
I had an idea to go for a speaker box of approx 400 x 500 x 250mm (16" x 20" x 10") or slightly smaller, using a sort of Onken design or maybe just a single slit, but nothing decided yet.
When it comes to an amp, there's an "issue". I am not going to play at Stockwood ... errr ... Woodstock, but at home and, if I learn more that one note at local events in our old folks club and I think 50W amperage will be enuff.
I've gotten a pair of simple 50W transistor amps built from cheap Chian kits and I guess one of these would be perfect. Else a similar kit from EliExpress is considered: THIS ONE.
For testing I have gotten a D-class chipamp, which had been nice as it doesn't requires a lot of space heatsinks and whatnot. A simple SMPS will do fine (it it works).
I love to fiddle with things and make things a bit diffrunt. I've got 50 shades of pink .. 2 actually for the bass and I will try to mix them in some "odd way". Also gotten a green pickguard that will match the pink body perfectly
.The speaker/amp combo will be covered in vinyl (black-ish) and apart from thinking of power amplifier, I must look up a decent preamp.
This is my plan and I am open for suggestions ... open for REASONABLE suggestions
, remember that this is a mid- to lowfi project. For fun. Low cost.Any speaker design people here? Spec's on the speaker.
https://www.masteraudionline.com/PDF-prodotto-1440/csx08.pdf
Bass guitar reproduction can be hard on regular speakers, not sure I would go with an 8", a 10" would be better. But since you have it the next step would be to plug the numbers into a program that calculates the response in a bass reflex box. Aw heck, down the rabbit hole again.
https://www.lautsprechershop.de/tools/t_box_vented_hoges_en.htm
Threw in the values and out pops 22.3 liters cabinet volume with a -3dB cutoff of 73 Hz, -8 dB at 57 Hz. The 'golden ratio' is said to minimize standing waves you divide the internal lengths by 1.61. So for a height of 460 mm / 1.61 = 285 mm, / 1.61 = 177 mm. Add the thickness of the wood to get your outside dimensions. I would think that this speaker will get hammered by the bottom octave of the bass as there is little loading of the cone below 70 Hz. Just tried it in a sealed box, -3 dB point of 141 Hz, -8 dB at 91 Hz. These are for a flat response, I am guessing that there are other calculators that generates different responses.
A possible preamp?
https://www.runoffgroove.com/ginger.html
https://www.masteraudionline.com/PDF-prodotto-1440/csx08.pdf
Bass guitar reproduction can be hard on regular speakers, not sure I would go with an 8", a 10" would be better. But since you have it the next step would be to plug the numbers into a program that calculates the response in a bass reflex box. Aw heck, down the rabbit hole again.
https://www.lautsprechershop.de/tools/t_box_vented_hoges_en.htm
Threw in the values and out pops 22.3 liters cabinet volume with a -3dB cutoff of 73 Hz, -8 dB at 57 Hz. The 'golden ratio' is said to minimize standing waves you divide the internal lengths by 1.61. So for a height of 460 mm / 1.61 = 285 mm, / 1.61 = 177 mm. Add the thickness of the wood to get your outside dimensions. I would think that this speaker will get hammered by the bottom octave of the bass as there is little loading of the cone below 70 Hz. Just tried it in a sealed box, -3 dB point of 141 Hz, -8 dB at 91 Hz. These are for a flat response, I am guessing that there are other calculators that generates different responses.
A possible preamp?
https://www.runoffgroove.com/ginger.html
I agree with printer, 8 inch is just not large enough. Even for guitar I would use 10 inch minimum, for bass 12 is more like it. The speaker is I think the most important part of the system, especially for bass. I honestly have never heard a bass amplifier with a small speaker that sounded good. Also, larger speakers are more efficient, so the power demand of the amp is less.
Thanks guys! I know there will limitations, but I am not playing with Black Sabbath or Kiss ... The speaker may be aimed for car audio systems and the magnets are massive, but that is just to be able to handle a lot of excess energy/heat. I was looking at drivers intended for audio .... PA/guitar/instruments and prices were much higher. And that is a crucial point - going for a bigger one would be a huge investment that my meager pension wouldn't really cope. This one was on sale. And even for a bass guitar, I would need a tweeter for some sloppy slapping.
Being 70+, I don't want to carry around a 200kg rigg, but something slightly larger than a Calvin Cline handbag would be nice.
Thanks Printer for the schematic. Finding preamp schematics for a "normal" guitar is easy, but I haven't really found something for a bass guitar.
Right now I am waiting for the darkness of the evening to come as I spotted a huge piece of plywood in the container.
Being 70+, I don't want to carry around a 200kg rigg, but something slightly larger than a Calvin Cline handbag would be nice.
Thanks Printer for the schematic. Finding preamp schematics for a "normal" guitar is easy, but I haven't really found something for a bass guitar.
Right now I am waiting for the darkness of the evening to come as I spotted a huge piece of plywood in the container.
Just grab it.
I would have a spare amplifier board around to quickly replace a bad one. They are hard to repair.
I would have a spare amplifier board around to quickly replace a bad one. They are hard to repair.
A final note before I go criminal, there's actually a not that expensive 12" driver from the same Italian company: Master Audio PA12/A.
For a complete different project I have a 10" woofer, Dayton Audio DC210 that I could use instead.
For a complete different project I have a 10" woofer, Dayton Audio DC210 that I could use instead.
Many current "percussive" bass players tend to like the sound of smaller speakers. Anyone remember the original Ampeg SVT with 300+ vacuum tube watts feeding 8 X 10 inch speakers. The second and third harmonic on those things were stronger than the fundamental. The very early (1969) vintage SVT used 6146 transmitting tubes. The design pushed the screen grids too hard leading to some spectacular flameouts. The amp also put out more power than a single eight speaker cabinet could eat, which led to blown speakers, leaving the amp unloaded with FIRE shooting from the OPT. I got to fix one of those after being at the show where it fried. After about an hour of thundering bass I could hear the raspy sound of one or more voice coils coming undone. Once the rattling became audible on stage it was too late.
Back in the 90's I made a lot of guitar amps that used car stereo speakers. I bought a van full when a local K-mart closed down. My biggest amp used a pair of early vintage Chinese KT88's to make about 50 watts. The tubes failed at anything over about 360 volts, so I use about 350 volts. My usual build used a pair of car speakers since they came two to a box. The best sound came from the 6 X 9 inch sizes and a pair of Audiovox branded speakers would eat a bass guitar at full crank from the 50 watt amp forever. I kept the last pair until the blue foam started to come apart. Yes, I had s friend that worked at a waterbed store. i got lots of off cut material......,.Naugahyde and Crushed Velvet used to be trendy, really!
I have not tried that particular Dayton 10 inch, but its resonance is below the range of a bass guitar, so you shouldn't run into X-max issues.
Back in the 90's I made a lot of guitar amps that used car stereo speakers. I bought a van full when a local K-mart closed down. My biggest amp used a pair of early vintage Chinese KT88's to make about 50 watts. The tubes failed at anything over about 360 volts, so I use about 350 volts. My usual build used a pair of car speakers since they came two to a box. The best sound came from the 6 X 9 inch sizes and a pair of Audiovox branded speakers would eat a bass guitar at full crank from the 50 watt amp forever. I kept the last pair until the blue foam started to come apart. Yes, I had s friend that worked at a waterbed store. i got lots of off cut material......,.Naugahyde and Crushed Velvet used to be trendy, really!
I have not tried that particular Dayton 10 inch, but its resonance is below the range of a bass guitar, so you shouldn't run into X-max issues.
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I have made several speaker cabinets from recycled wood. The speakers seen in post #12 were made from wood left from a re-roof job at a house near where I used to live in Florida. There were dozens of 4 foot by 8 foot plywood panels that had been removed from the roof. many were completely rotten, but some had reasonably large areas of usable material.
I made a pair of portable cabinets from wood that was "too thin for speaker cabinets." There are a pair of Dayton PA 165-8 drivers plus a "super bullet" tweeter. The PA165 is cheap, almost impossible to kill, and has an 80 Hz resonance. I tuned the cabinet for 70 Hz and wound up with a pair of speakers that work well for guitar even at really LOUD volume levels. They DO NOT LIKE the bass guitar even at low volumes.
Many years ago I grabbed a pair of "12 inch Eminence guitar speakers" from a closeout sale at Parts Express. I stuck one of them in a box I made whose size was chosen to be the largest box I could make from a given pile of plywood left over from a nearby construction job. The back is partially open, again the opening is determined by the size of the wood scraps used to make the box. The front and back panels are made from glued together scraps. The seam line is visible in the back as are the cracks running from the screw holes. This thing has a real nice full bodied sound with my 1970 vintage Univox branded Mostite clone guitar. It will als do a decent job with the bass guitar at basement friendly volume levels. It eats the 20 watt amp sitting on top of it at full tilt with a bass with no poping or undue distortion.
The "bridge too far" cabinet sits on the floor unfinished, since it tried to kill me. I was sitting on the bench of a wooden picnic table in the driveway painting the black "liquid Tolex" onto the cabinet when the bench broke dropping me over backwards onto the asphalt. I caught the remainder of the broken wood support right in a sensitive spot between my legs before smashing my head on the pavement. I have had blood in my urine ever since this incident last summer. This has started a chain reaction of invasive medical tests with two doctors convinced that I have prostate or blader cancer, though none of the tests have found anything. If it ever gets finished, the big hole gets an Eminence 15 inch PA speaker and the small holes get a pair of Dayton PA 165-8 drivers seen inside the cabinet. A big tube or hybrid amp is in the works to drive this thing fully bi-amped. I have a TI TPA3255EVM evaluation kit. It is a class D "chip amp" capable of putting 400 watts into that 15 inch Eminence at 1% THD. The HF channel will use sweep tubes.
I made a pair of portable cabinets from wood that was "too thin for speaker cabinets." There are a pair of Dayton PA 165-8 drivers plus a "super bullet" tweeter. The PA165 is cheap, almost impossible to kill, and has an 80 Hz resonance. I tuned the cabinet for 70 Hz and wound up with a pair of speakers that work well for guitar even at really LOUD volume levels. They DO NOT LIKE the bass guitar even at low volumes.
Many years ago I grabbed a pair of "12 inch Eminence guitar speakers" from a closeout sale at Parts Express. I stuck one of them in a box I made whose size was chosen to be the largest box I could make from a given pile of plywood left over from a nearby construction job. The back is partially open, again the opening is determined by the size of the wood scraps used to make the box. The front and back panels are made from glued together scraps. The seam line is visible in the back as are the cracks running from the screw holes. This thing has a real nice full bodied sound with my 1970 vintage Univox branded Mostite clone guitar. It will als do a decent job with the bass guitar at basement friendly volume levels. It eats the 20 watt amp sitting on top of it at full tilt with a bass with no poping or undue distortion.
The "bridge too far" cabinet sits on the floor unfinished, since it tried to kill me. I was sitting on the bench of a wooden picnic table in the driveway painting the black "liquid Tolex" onto the cabinet when the bench broke dropping me over backwards onto the asphalt. I caught the remainder of the broken wood support right in a sensitive spot between my legs before smashing my head on the pavement. I have had blood in my urine ever since this incident last summer. This has started a chain reaction of invasive medical tests with two doctors convinced that I have prostate or blader cancer, though none of the tests have found anything. If it ever gets finished, the big hole gets an Eminence 15 inch PA speaker and the small holes get a pair of Dayton PA 165-8 drivers seen inside the cabinet. A big tube or hybrid amp is in the works to drive this thing fully bi-amped. I have a TI TPA3255EVM evaluation kit. It is a class D "chip amp" capable of putting 400 watts into that 15 inch Eminence at 1% THD. The HF channel will use sweep tubes.
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I could not find PA12/A but a PA12/4
https://www.masteraudionline.com/en/product/pa12-4/
It has a paper surround compared to the DC201 which has a foam surround. I would think the paper surround one might have more highs. Thought about the original 8" speaker. I would build it and practice with it until you find you need something better. You can roll off the lower bass, as Tubelab says, many cabinets in the past did not reproduce the bottom octave much and relied on the second harmonic with the brain filling in the rest.
https://www.masteraudionline.com/en/product/pa12-4/
It has a paper surround compared to the DC201 which has a foam surround. I would think the paper surround one might have more highs. Thought about the original 8" speaker. I would build it and practice with it until you find you need something better. You can roll off the lower bass, as Tubelab says, many cabinets in the past did not reproduce the bottom octave much and relied on the second harmonic with the brain filling in the rest.
Just finished sanding the body with 320 wet paper. Next a 600 paper before painting it. I have no patience to make it ultra-super-perfect so good for me is ... good for me.
Found yet another alternative ... Damn you, now I am on the hunt for a BIG 12" woofer, and this one is just 10 miles away ... Bass Habit Play PL300.
Found yet another alternative ... Damn you, now I am on the hunt for a BIG 12" woofer, and this one is just 10 miles away ... Bass Habit Play PL300.
Not really keen on the 88 dB/watt/ loudness. With 20W you are looking at 101 dB output. Looked up the picture and it seems to be a subwoofer rather than a speaker for instrument use. Makes sense with the sensitivity if it is intended for a car. I think it might sound muffled for bass guitar given the polypropylene cone.
Whilst waiting for ... enthusiasm/strenght/time/whatever, maybe a good table saw, I started working on the guitar and ...almost ruined the headstock. The electric saw I borrowed came with just one blade for boards, so I made an attempt to shape the headstock with my router and that didn't go well. I've tried to squeeze glue into the cracks and have another emergency fix, but still, that ruined my elegantly planned shape.
I shredded a 12" HiFi speaker using it for bass. Culprit I believe was ULF transients the note would ride on, so your preamp needs a fairly sharp HP filter starting at, say, whatever drop D is, in case you want to use that tuning some day. Maybe allows use of a cheaper speaker?
Fighting a flu and spent all weekend at a conference and have also sanded down the ¤#%?%#"Ä paint andf reado to get another spray can and finish the paint job.
But I struck gold a week ago (at least I think so). A guy was clearing out his piles and gave away a Dynacord Eminent II:
Eminent II
Manuals
Maybe not the most perfect amp, but slightly powerful, lots of inputs and various options and will hopefully do.
But I struck gold a week ago (at least I think so). A guy was clearing out his piles and gave away a Dynacord Eminent II:
Eminent II
Manuals
Maybe not the most perfect amp, but slightly powerful, lots of inputs and various options and will hopefully do.