Sound Critter One - Part Four - Tone or no Tone?

I got back from lunch and shut the rig down. It still sounded tight, smooth lows and VERY punchy mids, and a nice high end that had a tendency towards brittleness. No shakes, rattles and rolls. Next step was to plug in the Pod. I installed and hooked up all my rack gear. Instead of rack rails I used 1x1 red oak strips in the rack portion to hold the rack screws, mainly because I'm cheap. I pre-drilled them and used 1 inch wood screws to mount the gear.

I powered everything up and started tweaking. For the maiden flight I used my number one guitar. A highly modified Bill Lawrence Swampkaster Tele. It's set up with a RioGrande Muy Grande Tele bridge pickup and a set of DiMarzio Class of '55 Strat pickups in the middle and neck positions. I also modded the wiring on this guitar for a 5-way switch and separate bass and treble controls and a chicken head volume knob.

After a quick tuning and a couple of strums I knew right away I need to start scooping out the mids using the mid control on the Pod. Alternately strumming and tweaking I started dialing in a decent sound. Having played open back or semi open back amps and cabinets for years I was apprehensive about the tone of the sealed and ported PA style cabinet. I did actually like the sound of the tight bottom end of the PA style cab. Using the Fender Bassman amp model I added the 2x12 cabinet model and guess what? I actually heard the tone of a 2x12 cabinet! Sweet. For the next hour I played with the Bassman, the Fender Twin reverb and the Class A-30 watt amp models. Awesome! Then for another hour I started dialing in the other parameters, mic'ing options, mic types, etc.

Bottom line... after a couple hours of playing and tweaking, I am VERY happy with the tone I am getting from this rig. To make the new cab start to resonate, adding it's on personality to the mix and representative of sealed back cabs you have to drive it harder than open back cabs, much to the chagrin of my neighbors. But overall I like the way the project turned out. The clean high fidelity reproduction of the actual tone the Pod outputs is definitely a goal worth pursuing! Since it was built from scrap material and leftover paint I only have about $22 in the whole project for the MDF and the casters. The 70/80 speaker turned out to sound pretty decent after all. It's not perfect but it's nothing the amp tone controls on the Pod can't handle. And never once did I have to touch the Pod's graphic eq.

I like it. I like the way it turned out. The tone, as always, is a work in progress but I am definitely happy with the results so far. They are very promising. If you want to get the optimum tone from your Digital Guitar Rig try this route. I think you'll be happy with the end product... TONE!

BTW, UPS just delivered the Eminence Delta-Lite II! I may have to write one more sound critter installment...

Sound Critter One - Part Three - The sound of music...

With the paint barely dry I couldn't wait to hook it up and see if I could get it to make a noise. I also wanted to, 1. check my wiring, 2. check for rattles and unwanted aural properties and, 3. last but not least check out the tone.

The Celestion 70/80 main driver that I installed is a low end entry level 12" 80 watt guitar/general purpose speaker. It has a pretty smooth low end coming into it's own around 175hz. It has a punchy mid around 2k and and sharp drop off around 10k. With this swell in response around 2-3k I expected it to be very middy. It wasn't the best choice for this application but it was good enough to test our proof of concept. The Eminence Delta-Lite II will be a much better choice for this rig. It's a Neodymium magneted 12" driver designed for PA systems. It has become hugely popular among bass guitar players for it's light weight and room filling tight bottom end. I'll give you a report on how it works out when it arrives.

The dome tweeter I used was a Boss TW-30 and was designed for car audio applications. It's frequency response was 2k to 20k. I was hoping for a pleasing crossover point. My crossover is fixed and unfortunately I could not find the specs on it. Fixed means the frequency at which it divides the sound is set at a fixed point, and is not adjustable. I have no idea what the crossover frequency is. To my ear it sounds like about 2k-4k. But even Google couldn't help me answer this question. I think it had CR-209 stamped on the circuit board.

Let me tell you a little about the rig I use. It's a Line 6 Pod XT Live pedal board, into a Carvin DCM-150 power amp. I do run the electric guitar into a Korg DTR-1000 tuner through an Audio Technica wireless. I A-B my acoustic instruments on a hard wire (guitar cable) thru the tuner and the Pod XT Live with an amp model set up for each one. I use the amp controls on the Pod for main EQ, and have the ability to get into the Pod's on board graphic EQ if more tweaking is desired. I was running this rig stereo into a 2x12 Avatar cabinet loaded with an 8 ohm Celestion Vintage 30 driver and an 8 ohm Celestion Greenback reissue. This trick of mixing drivers is a great way to get some killer tone, by the way. I thought this rig sounded really, really good. But with the rack case, the speaker cab and the pedal board it was a lot of stuff to tote to gigs.

I started out running some streaming audio straight into the power amp from my laptop with no eq. It worked. Sound came out. I checked the tweeter and it was tweeting. I checked the main driver and it was driving. So my wiring was good. I cranked it up and checked the air flow from the vented ports and they were venting and porting. The air flow from the ports was a little weak which I attributed to the 70/80. Tonally... well it sucked! It was honky as heck! But then I was pushing streaming audio from the web at 32k or some such silliness. Basically beach music with the guts ripped out by the codecs. I thought the 70/80 would be middy and I was right! I put aside the honky tones and cranked it up louder listening for shakes, rattles and rolls. It sounded tight. No issues in the build, no air leaks that I could find. No aural artifacts. And it was LOUD! But at this volume level the cabinet was starting to work giving the tone a little personality. Nothing like my guitar cabs. But clean and tight on the low end. And a glassy presence on top. The middle sucked though! Ha! It was honking like a flock of geese!

I let the fowl fly and went upstairs to grab some lunch. If anything was loose I wanted it to shake free now rather then later.

Sound Critter One - Part Two - Building notes...

The design of the speaker cab was based on the compact size I wanted, the specifications required by the Deltalite-II 2512, namely 1.5 to 3.0 cubic feet of internal volume and the need for a built in rack for the few pieces of rack gear I use. I wanted it all in one cabinet. I was prepared for it to be heavy because I wanted it built like a tank. I also had to have room for the tweeter and two 4 inch x 5 1/4 inch long ports. I wanted to incorporate a crossover so I had to plan a spot for it away from the sound insulation so the heat from the crossover didn't cause a fire.

I had a 4x8 sheet of 3/4 plywood left over from another project so that became my choice of wood for Sound Critter One. BTW, my son, a 7 year Navy veteran, came up with that name. I kinda like it myself. This plywood was not my first choice for this project. MDF and or Baltic Birch plywood wood have been great. The stuff I used is not void less, ie., free from knot holes and empty spaces between the laminated plys which cause unwanted resonances. It is not 12 ply and made especially for acoustic applications. It was however, very strong and heavy, it was very cheap (free) and it was sitting here in the way. I measured the rack I currently used (also homemade) to get the dimensions for the cab. I built it 14" deep. It is 25.5 inches high without the 2 inch casters. It is about 21 inches wide. The speaker cab measures 18x13x15 internally. This gave me a volume of about 2.4 cubic feet, well within the specs for the Delta-Lite II.

The baffle and the rear of the sealed cab were from 1/2 inch MDF. This is a much better choice for the sound baffle than the plywood. 1/2 inch or 3/4 inch works fine. A half inch inside the front and back of the cab I installed 1x1 bracing around the perimeter of the opening to give purchase for the rear panel and speaker baffle screws. Once the bracing was installed I sealed every joint, crack and seam with 100% Silicone sealant to stop air leaks. I ran a bead along the front side and the back side of all the bracing. I wanted to make this puppy air tight! All the joints in the cabinet were glued and screwed during assembly for strength.

Next I installed the rear panel. I used a bead of adhesive weather stripping around the perimeter of the door again to get a good air tight seal. I pre-drilled pilot holes for the 1 1/4 inch wood screws and fastened the rear panel. Once the door was installed I used 2 inch thick pieces of fiberglass insulation to line the interior of the speaker cab to stop unwanted resonances. I stapled it just to the inside of the case in the corners and in the centers so as not to completely crush the 2 inch thick panels. I left a gap in the insulation on the bottom to mount the crossover.

The trickiest part was cutting out the holes for the speakers and the 4 inch ports. But it wasn't really all that bad. I first cut the soundboard or baffle to fit the opening. Next I laid everything out on the panel to get a sense of spacing and what goes where. When you do this remember to allow for the internal bracing thickness inside the cab. Draw a line diagonally across the baffle from each corner. Where the lines intersect is the exact center of the baffle. Once you get everything centered and laid out, mark everything well with a pencil. I used a jigsaw to cut out the openings. I used a fine metal blade for a fine smooth cut. Once cut out I marked and drilled all the mounting holes for the speakers and the 5" long by 4" diameter PVC ports. I glued the ports flush to the front panel with Silicone adhesive.

With the back on, sound deadening insulation installed and the baffle cut out I was ready to do the electrical part. I drilled a hole in the top of the speaker enclosure to pass the speaker wire into the box from the rack area. Wiring a crossover is easy. In a two-way crossover you typically have two input connections, + and -. You have two + and - connections each for the woofer and tweeter which are sometimes marked w-, w+, t-, t+. Simply attach the input + and - wire from the amp to the corresponding points on the crossover. Same with the Ws and Ts. Attach the + and - terminals on the crossover to the + and - terminal on the woofer and tweeter. Depending on the type of crossover you have you may have to do a little soldering. Once all the wires were attached I installed the crossover in the box away from any insulation. It is much easier to do the soldering outside the cab.

With all the holes drilled and cut and the speakers and port tubes mounted on the baffle, and the wiring done, I removed all the components and spray painted the baffle flat black. I used spray can flat black truck bed liner to paint the outside of the main box. While it was drying I attached the four swivel casters to the bottom. Once dry I screwed the speaker baffle to the box. I did not use any adhesive when I attached the baffle because I want to be able to remove the baffle to replace\tinker with components. I did use a touch of Silicone to seal the hole that I had cut in the top of the box around the speaker cable.

Standing back and looking at Sound Critter One my first thought was this thing is a tank! LOL! It looks like I have finally built the guitar rig I have been pondering for 3 years! All that was left was to hook it up and see how it played.

Sound Critter One - Part One My latest digital guitar project...

Being a guitar tone snob is not easy. Sometimes you have to admit you were wrong. I was a tube bigot for many years. But consider Digital Guitar Rigs, or DGR's for a moment. The tone you can get from digital preamps and processors like the Boss, Zoom, TC Electronics, DigiDesign, Digitech or my personal favorites the Line 6 products, can be amazing. I know, I know you tube purists are thinking no DGR sounds like your nirvanic tiny tubed magic tone charmer. Well, it depends. It depends on the person setting up the parameters. It depends on how you reproduce the sound. The tone coming out of these pedals is very good with the necessary tweaking. But of course, you may not realize that since you tried to play it through your guitar amp.

You can't take a modeling preamp and run it through your guitar amp and cabinet and expect to hear the nuances of the tone that the DGR produces. Why? Because your amp and cabinet and speakers and even the room you play in affects your tone. It colors the tone. It may sound great and it may be the tone you were looking for. Or it may not suit your aural tastes at all. But it carries the sonic personality of your guitar gear. Now as tone snobs... do we stop there in our quest? I say nay, nay! It is an evolving process. The search is the important part, not the end results.

I've owned 20 different guitar amps, and who knows how many pedals over the years looking for tone, mostly in all the wrong places. I've only had a couple of DGRs. But I like them for several reasons. The tone is good now. It was less so 10 years ago. But things have changed. Better hardware, faster processors, better software and advanced digital signal processing have completely changed the face of DGRs. I like other things about digital rigs. The repeatability. It will sound the same tonight as it did last night. Not always true with tube type amps. I like the ease of setup and tear down. I like the fact that you can achieve your tone at almost any volume level. Whether you are playing at the coffee house 3 feet away from a few couples or playing a dance in a college stadium. I like the variety of amp and cabinet models. I like being able to find optimum tone for my electric guitar, my acoustic guitar, my fiddle and my mandolin all on one rig. So DGR's have some appealing traits.

We played a show in Nashville and our guitar player ran his Line 6 Pod XT Live into the house pa and also into a small pa amp and a Peavey SP-5 on stage for a monitor. He went on and on about the tone he got from his XT Live. It got me thinking that maybe we need to run these rigs thru more of a PA system than guitar amps.

The tone of a DGR is arguably better thru a sound system than a guitar rig designed to work within a more narrow range of frequencies. But I am a guitar player and I didn't want to give up control of my stage volume to the sound guy. I wanted an amp I could control on stage. I tried the XT Live thru power amps and into guitar cabs. 1x12's, 2x12's and more. I turned off the cab modeling on the Pod and let the cabs sing. It sounded great but it was a pain dragging all those cabinets and rack cases and guitars and processors around. I wanted simple tone. I wanted compact tone. I wanted to lighten my load. I always said I played for free. I got paid for lugging all my gear!

What is it they say? "necessity is a mother..." So here is what I dreamed up...

This is basically a PA cabinet and speakers with a rack on top for my tuner, power supply, wireless and power amp, plus a couple extra spaces. The speaker cab is roughly 14dx16hx19w. It is a sealed ported/vented design. I want to share the construction process with you, in case you feel the need to seek tone on this path.

The speaker is an old Celestion 70/80 that I had laying around. I didn't expect much from it since it's a general purpose speaker made for guitar and small PA applications. Boy was I surprised! I have ordered an Eminence Delta-lite II 2512 and it should be here next week. So I built the speaker cab to the specs on Eminences web site. http://eminence.com/pdf/cab-deltaliteII2512.pdf The 2512 has a pretty smooth roll off after 2k so I added a Boss TW-30 tweeter to the cab to get my desired sparkly twang. The ports are 4 inch in diameter and 5.2 inches long.

Construction notes follow...