Help me design a cabinet and choose some speakers

[Freeman Keller]

Last spring I built a nice little 6/12 watt kit amplifier which I really like. A pair of 6L6's, nothing fancy, just nice clean sound. At the time I had an old Gibson cabinet with a single 12 inch speaker and a dead amp - I mounted my kit in the cab and have been playing it that way ever since.

 

I'm getting ready to repair the Gibson amp so I need to make a new cabinet for the kit. Notice I said "make" - I think I'm perfectly capable of building a speaker box. I can design my own plans and would probably base them on the Gibson cab, but if anyone has a source for good 1 x 12 speaker cabinet plans with the head hanging from the top I would appreciate a link. I haven't decided if I want to build it out of birch ply and cover in Tolex or use some nice wood and make it furniture (probably the latter)

 

The part that I really need help with is choosing a good, reasonably priced 12 inch speaker. As I said above, I mostly play clean and at relatively low volume levels - this is for playing in my home music room. I play both my LP and Tele clones thru this, once in a while plug a weissenborn with a mag pickup in too. The amp is rated at 12 watts (I think a pair of 6L6's is good for 15) so I don't need high wattage speaker. Price is a consideration, but not a make or break deal. I will have to order it - no one in town stocks anything like this.

 

So, what would you use if you were me?

[billybilly]

Weber offer good products at good prices. Their California is really good for cleans, I think it is a take on the JBL D120F... http://www.tedweber.com/cali12f

 

Here is their main website.http://www.tedweber.com/speakers

 

Lots of choices, makes choosing hard, good luck.

 

 

[t_e_l_e]

i have put in my tweed royal (which also switchable between 6 and 12w) a jenson P12R for originality of the fender tweed.

but this speaker lacks in efficiency and as i play at band volume and like to crank it, it lacked in volume and sounded farty. i really hated it.

 

then i got a celestion vintage 30 and could not be happier with it. through its efficiency it has the volume and also has space left until the speaker is in its limit. which means much more clean headroom.

i guess the jenson with its 25w rating was already pushed to its limits when the amp was cranked and therefore not sounding good anymore.

 

you cannot go wrong with a celestion vintage 30, you will have really nice clean sounds.

 

if you look at something else

i would not buy a speaker with an efficiency/sensitivity less than 98db (my jenson has 95db the celestions has 100db)

a speaker rated only for 25W may already be pushed to its limits with your amp, so buy one with a higher rating (the vintage 30 is rated for 60w)

 

you do not need to spend crazy money for a celestion blue alnico to get a nice sound

[t_e_l_e]

PS: if shiping wouldn't be that expensive i would just ship my almost unused jenson in its orginal box over the pond to you. if you like it keep it and we would find a price, and if not just send it back.

 

but i guess sending this box back and forth will be alone up to $100....

[Mr Temporary]

Building an open back cab is really pretty easy, and the dimensions are not all that critical. If you're going to be gigging with it, then I'd forgo the "furniture" look and stick with Tolex. If it's for the house or studio, then I'm a big fan of converted old radio and phonograph cabinets.

 

Only suggestions I have are to bit the bullet and get Baltic Birch (no void) ply instead of the home improvement store stuff, or worse yet, MDF. Box/Finger joint or dovetail the corners, get some hardware corners from PartsExpress, and Tolex from Antique Electronic Supply.

 

For a speaker, I suggest listening to a few and seeing what you like. You could do worse than a Vintage 30, and I've been happy with some of the Eminence speakers. Their website can provide some guidance. If it were me, and I was looking for something clean and portable, I'd take a listen to some Neo speakers from Jensen, Eminence, etc.

 

[t_e_l_e]

oh and what i forgot to mention the vintage 30 weights almost 5kg whereas the jensen is less than the half of it

[Phil O'Keefe]

Speaker selection is such a personal thing... kind of like guitar choices. There's really no right or wrong answer here, but there are some things to consider. First, make sure it can handle the wattage you are going to hit it with, and second, make sure the impedance rating is a good match for the amp's output section. Then it becomes a matter of tone and taste... do you want early breakup, or for the speaker to stay clean throughout the amp's volume range? Speaker breakup can add considerably to distorted sounds, but if you rely on pedals more than amp breakup, a cleaner speaker might be a better choice for you.

 

AlNiCo vs ceramic magnets is another personal choice... I like the sound of AlNiCo speakers, but they tend to cost a bit more and they tend to not do as well in terms of speaker efficiency (how much of the incoming power is converted to acoustical energy as opposed to heat), but unless you're playing live and need to maximize the amount of SPL the amp can crank out, that shouldn't be a big problem, especially since you don't need a speaker that can take a ton of power.

 

On a really tight budget, the new Jensen ceramic speakers are actually pretty decent. Something like a Jensen C12R would probably do you just fine. I also am a big fan of Weber speakers, and they can provide you with lots of different options.

 

Do you happen to know the name / model of the speaker in the Gibson cabinet you've been using? That might be a good place to start when considering a replacement, or for us to use as a point of reference for comparisons and suggestions.

[DeepEnd]

Some general stuff: Depends on what kind of sound you want. If you want a classic Brit sound, go with Celestion; if you want a classic US sound, Jensen or Weber; if you want a modern US sound, Eminence. As Mr Temporary said, an open back cab is fairly easy. If you're building a closed cab, find a Thiele/Small calculator such as this one: http://www.micka.de/org/en/. You'll want to make the dimensions multiples of prime numbers like 3, 5, 7 or 5, 7, 9 so you don't get unwanted resonances.

[Phil O'Keefe]

I definitely agree with the idea of going with Baltic birch and Tolex if you're going to gig the cabinet, and finished high-grade wood if you're going to use it exclusively at home or in a studio, or nearly exclusively. I suspect you can make an incredible looking wood cab Freeman, but I'd hate to see it get thrashed at gigs.

[Freeman Keller]

Thanks everyone. The Celection Vintage 30 is one that I had looked at and book marked - it is about half the price of the classic blue one and the descriptions I read about it seems to match what I think I want.

 

Phil, the Gibson cab has a Legend "Eminence". I had always been under the impression that neither the amp nor the speaker was held in very high regard - it was used when I got it, pretty inexpensive but was OK for my first amp. When the amp died last year I built a little kit and put in the cabinet, but its time for the kit amp to get its own box and speaker.

 

I don't gig out and actually don't play electric all that often. I'll probably build the box out of some nice wood - walnut or something. It will spend its life in my music room - since I'm planning on getting the Gibson amp fixed if I ever do want to go somewhere I can take it. The box will be open backed with the amp hanging from the top - somewhere around 24 wide and 20 tall.

 

I built my own bass reflex loudspeaker enclosures about 45 years ago and they still fill the house with music. I hope this will be the same.

 

[billybilly]

Here's the thing about taste and subjectivity. The Vintage 30 hurts my ears (piercing, shrill)... In other words, all opinions other than your own may even be irrelevant in choosing a speaker.

[Grant Harding]

My Bogner Shiva is a 2x12 open back combo with Vintage 30s and they work perfectly in that amp to me. Warm, fat, and tight.

 

Pretty sure Reinhold designed the amp and speakers to work together, so it's not like arbitrarily swapping out a stock speaker for one.

[WRGKMC]

I bought a pair of Webers that are similar to Jensens. I bought them on recommendations from others on this site and got them at a good price but to be honest I'm not impressed with them. They make sound of course. I own actual Jensens and the Webers don't come close to their tone or tightness. I haven't tried any of their other speakers like the one you posted but given my experience on the ones I do have I'd buy a used JBL over a clone any day.

[WRGKMC]

Last spring I built a nice little 6/12 watt kit amplifier which I really like. A pair of 6L6's, nothing fancy, just nice clean sound. At the time I had an old Gibson cabinet with a single 12 inch speaker and a dead amp - I mounted my kit in the cab and have been playing it that way ever since.

 

I'm getting ready to repair the Gibson amp so I need to make a new cabinet for the kit. Notice I said "make" - I think I'm perfectly capable of building a speaker box. I can design my own plans and would probably base them on the Gibson cab, but if anyone has a source for good 1 x 12 speaker cabinet plans with the head hanging from the top I would appreciate a link. I haven't decided if I want to build it out of birch ply and cover in Tolex or use some nice wood and make it furniture (probably the latter)

 

The part that I really need help with is choosing a good, reasonably priced 12 inch speaker. As I said above, I mostly play clean and at relatively low volume levels - this is for playing in my home music room. I play both my LP and Tele clones thru this, once in a while plug a weissenborn with a mag pickup in too. The amp is rated at 12 watts (I think a pair of 6L6's is good for 15) so I don't need high wattage speaker. Price is a consideration, but not a make or break deal. I will have to order it - no one in town stocks anything like this.

 

So, what would you use if you were me?

 

Knowing the type of music you play is important as well as the cab type. An open backed cab vs a closed back cab is going to cut your most suitable options in half. I know you build allot of semi hollow guitars and are into acoustic building. If I were to guess you'd want something that would make those kids of guitars sound good and can forgo any kind of speakers targeted towards heavy rock or metal.

 

If you want something that produces great clean tones, the choice would be different then choosing something for rock.

I can give you a few general suggestions but as other mentioned the choice will be yours to make.

 

If the amp produces a maximum of 12 watts then you don't need a high powered speaker. 25~50W max should limit your choices down. You can run high wattage speakers but the low volume sensitivity and dynamic response are affected because you're barely moving the cone. The speakers spider and cone material is going to be much stiffer and subtle accents picking the strings will be diminished.

 

A lower wattage speaker will have a lighter cone and its excursion will be closer to the 50~70% target range where most speakers properly matched to the heads sound best. Musically you'll have better dynamics and string touch sensitivity.

 

The speakers SPL rating is the next item. The higher the SPL the more efficient a speaker is at converting wattage to sound. Many speakers are over 90db these days which should make a 12 watt amp gigable. Allot of vintage speakers are under 90db and they rob the amp of allot of power.

 

Going too high on the SPL comes at a cost. The cone becomes too lightweight and can be flabby for allot of music. Someone playing rock may not mind it because they are running clipped signals anyway and dynamics isn't a major concern. You can look up the specs and get a general idea of the SPL ranges.

 

Next item should be the choice between open backed and closed backed cabs. Different speakers can do better in different cabs. Jensens are commonly used in open backed cabs. Their SPL is a little lower then others in the mid 90's but the cones are well suited for open backed cabs. They produce what's called the American tones which can range from a nice jangle when cranked or nice clean Jazz tones when dialed back and treble rolled off. You can do well playing Country, Rockabilly Jazz and blues with them with the right head and cab. Fender got their signature tones with Jensen's, Utah and Oxfords (none of these original companies are in business any more but the new Jensen's made in Italy are very close to originals)

 

Celestion are what's considered to be the British tone. The green backs produce allot of mids and the heads used like Marshalls push the speakers upper end to flatten out their response. When teamed with a Fender type head they can sound very muddy. They do make other speakers now which are more full ranged. I have some 75's which do a good job producing a flatter response and I can get Fender and Marshall heads to sound right with them.

 

High SPL speakers are often designed for closed backed cabs. The air volume of the cab acts like a shock absorber and prevents the cone from over excursion. These cabs should be designed using the speaker specs and a calculator using those specs to find the optimal air volume needed for that particular speaker to get the best results. Too little or to much air causes bad things to happen with the speaker. You can have rogue frequency bumps or dips which will drive you nuts at lower volumes . The speaker can sound overly compressed or just flab out on you at higher volumes. Sealed cabs will likely be larger and heavier then open backed cabs if they are properly tuned. Ported cabs are rarely used for guitar because the instrument produces mostly midrange tones and the port is for bass response which isn't needed. Maybe some jazz players might like it.

 

Given the fact you build guitars and would likely want to hear what the guitars sound like (without those frequency bumps) You'd either want to use a cab design calculator to get the sealed cab design right or just go with an infinite baffle open backed cab which doesn't have those design issues. You can make a open back cab with little or no calculations and still get a very flat response. without the air volume size restrictions involved in building a closed back cab. Just be sure you narrow down the speaker choices before you design the cab. Allot of people build the cab first and wonder why the sound sucks after the speaker is installed.

 

Cabs are built around speakers not the other way around. Open backed gets you the best results especially with lower wattages. The speaker is free to move and has less design issues. If you want a deeper bass response simply make the cab an inch or two deeper.

 

Again, the speaker choices for either of these will be important here. You can get some compensation using your amps EQ settings but the ideal cab and speaker will make the guitar sound great with the EQ settings at 12:00. The EQ will simply let you target the pickups and not have to be used to compensate for a flawed cab design.

 

If you can narrow down some of these options you might choose it will be allot easier to rule out the speakers that will be a bad choice for the cab design leaving you with a targeted speaker selection that you can decide on.

 

 

[BG76]

There is a book called 'How to Build Speaker Enclosures'. Buy a copy and read it a few times. I have built a lot of speakers over the years and the knowledge contained within this book combined with another book that Altec Lansing published around the same time are great resources.

 

An enclosure is very important.

[billybilly]

Warm? Wow, that's a new take on the Vintage 30, must have been in the design.

[billybilly]

So, based on experience with one of their speakers, you're discrediting the entire line? That's your choice.

[Freeman Keller]

Interesting that the page I printed from a company called Amplified Parts says "the Vintage 30 features enormously detailed and complex overtones, a warm low-end, a famously rich vocal mid-range and a beautifully detailed top-end"

 

I guess different people hear things differently.

[t_e_l_e]

^freeman, i guess they mean overdriven/distorted sound

there are not that overtones when playing clean...

 

for me it is almost not possible to play really clean with my 6/12W amp. there is always some grit at least

[WRGKMC]

If its an open backed cab just take a tape measurer to a music store and copy the dimensions off a cab similar to the one you want. Slight changes in size have little effect.

 

If you want a more organic tone you can do like fender did and use a thin speaker baffle that's supported on two ends. The other two sides were free to move. The baffle would vibrate much like an acoustic guitar top does and produce more bass tones for the amps size. I've done this myself on lower wattage cabs and it really does sound cool. It doesn't work well with higher wattage amps because they begin to rattle but for a single 10" or 12" its a pretty cool option.

[DeepEnd]

. . . Phil' date=' the Gibson cab has a Legend "Eminence". I had always been under the impression that neither the amp nor the speaker was held in very high regard - it was used when I got it, pretty inexpensive but was OK for my first amp. . . .[/quote']

Gibson isn't known as an amp company but Eminence speakers are very good. They also tend to be good bang for the buck, which is why you see them in lower priced amps.

[Phil O'Keefe]

Yeah, there's nothing wrong with Eminence speakers. If you like the sound of the Legend with your kit amp, you can find another one fairly easily, and they're not all that expensive - comparable in price to the Jensen C12 I mentioned previously.

[Freeman Keller]

Thanks, DE and Phil, that's good to know. I really don't know jack about the sounds of different amps and cabs - I've listened to lots of electric guitars over the years but don't know how much of the sound is amp, speaker, guitar, effect or player. Until it broke the Gibson sounded pretty good for my style of playing - bluesy jazzy stuff at modest volume without much distortion. I mostly play the neck pup on both the lester and the tele. Not very exciting, am I?

 

Since the kit amp (6L6's) is pretty similar to the Gibson (6V6's) maybe I'll try a slightly different speaker to see what effect that brings. Remember, right now the Gibbie is broke - once I build this new box I plan to have it fixed.

[WRGKMC]

I'd think an American voiced speaker will likely suit your playing better then a British voiced with that amp.

Since the head was built for a kit I suspect its a Fender clone of some type and has similar voicing.

If you go with a British voiced speaker you may have issues with your tone control ranges not matching the speakers frequency response.

 

Eminence Legend GB128 is a good choice They are decent speakers for the price. This one has an SPL of 101 which will make that little 12 watt loud enough to play with a live drummer. http://www.parts-express.com/eminenc...8-ohm--290-488

 

Celestin type A might be another. Its SPL is a little lower but still plenty good enough to play live. http://www.parts-express.com/celesti...-ohm--294-2321

 

This Eminence TF-1250 is in the same range too. Its got a better SPL and produces vintage American tone. http://www.parts-express.com/eminenc...aker--290-4914

 

I'm still partial to Jensen Alnico P12N for low wattage amps.

 

Many of your Gibson amps used them to get those good semi hollow body tones from their jazz guitars.

Alnico speakers have a unique tonal character and compression you don't get form the harsher sounding Ceramics.

When you drive them up the saturation comes on gradually and warmer then a ceramic which is more like brick wall in comparison.

 

The Jensen site has sound clips of their speakers. You might want to give them a listen.

https://www.jensentone.com/vintage_alnico/p12n

 

 

Eminence makes some alnico speakers too but I think the Jensen's are a better build and buy.

Celestin makes some really nice alnicos. You pay an arm and a leg for one new or used.

[Freeman Keller]

I performed a little experiment last night. I have this VOX thing they call a "modeling effects processor" - I primarily bought it to experiment with different effects without buying a whole lot of single units, but it has the ability to model 33 different amplifiers and 11 different speaker cabinets. I had totally spaced out that it models the cabs - I've fooled around with the amps before but really had not tried the speakers.

 

Anyway, I set my amp as clean as I can, remember it is playing thru the Eminence speaker and I set the Vox to a clean amp with no effects. Then I just sat there and switched from one cabinet to another, played the same little riff, then something else. I don't know how accurate the models are but frankly there is a pretty noticeable difference and some I like a lot more than others.

 

In order of my preferences, I really liked the VOX AC15 and AC30. I liked the Tweed 1x12 (which I think is a Hot Rod with Eminence speaker) and the black face 2x10 (Vibrolux?). I actually liked the little Tweed 1x8 (Champ). Hated all the Marshall's, the Tweed 4x10 and the VOX AD120VTX.

 

So, based on that I'm leaning towards the VOX sound which I guess is the Celestrion blue or vintage 30 in an open back cabinet (the amp will be in it too - I need some air circulation. Or should I do 2 ten inchers.....