TUBE AMP SPEAKERS--THE MOST OVERLOOKED ASPECT

Hi and welcome..............................if you've read our other music-related guides (authenticmooretonemusic) then you know, we are Mooretone Music, LLC.  Our forte is and has been Hand Crafting custom vintage-style guitars, and single coil pickups, while incorporating our recommended  modern day upgrades and betterments.  After 25-years as a Musician and 14-years building guitars with many more years of performing guitar repairs, modifications and other services, Mooretone(TM) decided to get involved in Custom Vintage Amplification--Tube Amps.  Why?  After so many years of purchasing all types of amplifiers from vintage to new modeling amps, none could deliver on what we wanted to hear, so we decided to do it ourselves--what a great ride it has been--and it has been just exactly what we needed to do! 

Before we get into this "Guide", there are a couple things, that I'd like to share with you--ideas.  First............I think it's fair to say, that most successful "Guitar Legends", first had talent and a vision for it, then technology to back it up, then modified technology to hone it and shape it into their "Signature Sound".  This "Guide" therefore, is not meant for the "Expert" who is already "Technically Saavy".  This is for those looking for some ideas. There are so many speakers and variables that exist, which all can have profound affects on that which works versus one that doesn't, that there is no absolute "Guide".  Here is an example of an anomale which can profoundly affect your musical presentation.................an amplifier's circuitry has tons of caps and resistors, but just one .50 cent capacitor in the tone shaping stage (usually the very first stage) can change a frequency produced by your amplifier, up or down, which can drastically affect the guitar being amplified!!  Speaker choices are no different--they can and will actually change the dynamics of all frequencies with the most drastic results--you just have to know a couple basics so you don't get too drastic and find yourself wondering what the heck just happened.  Makin capacitor changes to an already marginal or pivotal amplifier that just need the right speaker to nudge things, should be a last resort  So, speaker are safe, easy and fun to play with but there are some things you have to abide by:

1.  Impedances--Speaker Coils and Output Transformers

2. Speaker Wattage or Power Handling--RMS and Peak

3.  dB Rating--Sensativity per-Watt

First, the Impedance.  The "Impedance" is hugely important for several technical reasons, but for here and in this "Guide" the only thing you need to know,  is that all amplifiers have an output transformer with inner wire windings as do all speakers have a voice coil.  When the two are not matched in terms of Impedance or the opposition that a speaker produces to the alternating current coming from an amplifier--the lower the impedance, the more power required--one of two things can and usually happens.......................either the inner wire windings of the transformer gets damaged, or the the speaker's voice coil can overheat and burn up or simply damage inner shieldings and develop "Voice Coil Rub"--an audible distortion at a specific volume.   "Voice Coil Rub" usually is due to an Impedance mis-match which can also occur from a damaged Output Transformer.  The good rule of thumb in keeping yourself grounded and things simplified..................if your amplifier manufacturer calls for a 4 Ohm speaker load, but uses two speakers as in a Twin Reverb, they are wired in "paralell"-- two 8 Ohm speakers in parallel will equal a 4ohm total load.  Do not buy two 4 Ohm speakers and then wire them in parallel!  Two 4Ohm speakers in parallel, equals 2 Ohms total which is guaranteed to damage your Output Transformer and or the Speaker's Coils.  We won't get into all that here, but just know.......................if your amp came with 2x12" speakers, and each is rated for 8Ohms but your amplifer states a "4Ohm Total Impedance".................they are two 8 Ohm speakers wired in "Paralell" and as such.........................you need to stick exactly to that which is known.  Do NOT buy into the hype that Attenuators or "Hot Plates" are a good option for creating distortion at lower levels!  This is without a doubt, the worst invention I have seen being sold!  All amps are designed to run within a certain AC voltage range--Output Transformers and Speaker Coils are designed to handle a specific "Load" so that the Output Transformers and Speaker Impedances are matched to one another.  Adding more voltage by plugging into things that produce higher AC voltages, is a modern day gimmick that will guarantee you disasterous results eventually.  You can get the same affects by properly choosing speakers or amplifer models which specify wattages more closely matched to your needs--change amplifiers if you have to--burning up a perfectly good amp is just dumb!  Impedances are something you don't want to experiment with or use outside influences to alter.  In some case like with a Peavey Amplifier, the manufacturer will specify how you can wire your speakers to meet the proper Impedances.  In fact, Peavey often has an Impedance Selector as does a Marshall.  Fender vintage amps do NOT.  So keep to the Manufacturer's specifications.  There are ways you can wire speakers to get to your Impedances specifications, but we aren't going into all that here.  It is best to simply replace what is there, with the same, but using options from various manufacturers--Celestion, Eminence, Peavey, Weber, Tone Tubby, Jensen, etc, etc......  In general, you can simply change Brands and get a whole different sounding amplifier while staying within proper operating ranges as specified by your amp manufacturer.

2.  Wattage or Power Handling Ratings--RMS simply and most easily remembered is the speakers "Continuous Power Handling".  Typically the "Peak" rating is 2-times the true RMS rating.  Again, we can talk science or keep things grounded and simple.  If you tend to play your amp at full volume, you will need a high RMS rated speaker.  Reason?  Any speaker's rating simply refers to its coil's ability to dissipate AC power continuously without suffering damage.  Output Transformers also have such ratings and again, it is important to keep Impedences properly matched between the two--speakers and transformer.  "Peak" is kind of a silly rating when it comes to Musical Amplifiers, as most of us don't turn volumes up to their peak, for short bursts!  So, the RMS ratings of a speaker should match the levels of volume you typically ask from your amplifier!  This can get complicated, but again there are safe rules you can follow in keeping to the basics.  Using the Twin Reverb as a generic guide, typically they come with 80 Watt RMS speakers--2x80=160watts of total RMS which is usually more than enough to dissipate the heat created by your Output Transformer working at 75% of its peak--which might be the usual volume you play at.  However for me..............since I ask about 90-100% of my amplifier's Output Tranformer, I look for larger voice coils and usually ones that are vented with RMS ratings anywhere from 2-3 times the minimum recommended rating.  Many in the industry will argue that my choices may not allow the speaker to fully open up--which is sort of a myth.  The fact is this.............you can run any speaker you want in any amplifier--irregardless of Peak or RMS ratings.  Why?  Because "Cut Off" is the moderator.  High Frequency "Cut Off",  is where you push a speaker into cutting off your High frequencies.  And at what point does your amp push your speaker into cut off, cannot audibly be heard up close to the amp.  If you really want to test your amplifier, you have to have someone else play your guitar, and then walk maybe 20 or more feet from the amp, and listen.  The human ear cannot handle the stimulus of a high powered amp speaker up close--above 90dB and your ear's sensory system overloads.  However, step back and take a listen.  So, the idea of Guitar amplifiers is to produce frequencies your audience can hear and not necessarily what you hear while being ontop of the amp--on stage for instance.  This is the very reason, we at Mooretone, like the Eminence "Commonwealth"--225Watt speakers at 100dB.  They can handle our amplifier's 100watt Output Transformer, with large 4" coils that are also vented!  So, I can make my amp loud continuously, with speaker coils that can handle the heat due to its vented dissipation feature.  But, if you add the numbers................225 Watts each x 2 = 450 Watts RMS or 3.5 times the necessary RMS rating.  However.............listen to my guitar from 20-feet or more distances, and the sound is gorgeous, clear, with full Bass, Mids and High frequencies that are well balanced and appealing to the listener--this also allows for my distortion to come from the Tubes and not the speaker's Voice coil that cannot handle the AC dissipation produce by an overly hard working Output Transformer.  The rule of thumb..............keep the combined RMS of both speakers to at least 2 times the rating of your amp's Output Tranformer--at 3/4 maximum rated wattage!  We usaully like around 2 1/2 times for safety and good musical presentations that aren't muddy or garbled and in-general................won't cut off to inaudible grunge or flapping noises--the sounds of a speaker self-destructing. 

Finally.........................each speaker should advertise its Sensativity or "dB rating".  The easiest way to say this is.....................the higher the dB rating, the louder the speaker per-watt or is it?  "Noises" by definition, are those "Sounds" which are unwanted--or that which is unappealing.  A chainsaw for instance produces about 110dB of noise--unless you are a Logger and urn for that sound, most consider it "noise" and thus unappealing.  Therefore, in Music, you want to produce Sounds that are appealing and at levels the human ear can tolerate before being pushed into sensory overload--thus becoming noise--and science says that happens about 90dB!  A speaker's ability to produce clear balanced and blended Frequencies such as Bass, Mids and Trebbles or Highs, are directly proportionate to its dBW or "Decible per Watt rating".  Keeping in mind, the rule that the human ear cannot detect "Cut Off" above 90 dB, until you are distanced from its source.  However, a high powered speaker with a high dB rating, produces audible frequencies which can then be tapered or structured by changing capacitors within the tone shaping  segment of the amplifiers circuitry--remember earlier (above) and that .50cent capacitor I mentioned?  Secondly, this is the very reason, that I as a Musician, refuse to mic my amplifier(s) while playing live--the "Sound Board or Mixing Board Engineer" typically modifies and reproduces an on-stage amplifier's sound, which is then sent out through "Loud Speakers"!  Those speakers can have 1,000Watt RMS ratings and produce typically 140dB of "N  O  I  S  E"!  Ever heard the saying.........."If it's too loud, you are too old?"  Now, condider that human ear cannot detect "Cut Off" above 90dBs while ontop of the amplifier--sensory overload.  But listen to that amp from a distance, and as the distance increases Cut Off,  is more easily detected!  Therefore, a high Watt RMS combined with a high dBW rating, is most likely going to produce Frequencies that are less prone to irritating sensory overload--at any distance!  Ironically, we at Mooretone, have been wrongfully ousted for this theory, which is, "those who think lower powered amps propped up on a chair or amp stand pushed into low powered "tube clipping" and then being miced through a mixing board where their "Sound" is re-engineered and delivered to the audience via "Loud Speakers", sounds better or more "Bluesy" versus a high powered amp with high watt, high dB speakers un-miced or re-mixed.  The fact is, that in truth, those lower powered amps simply sound good on stage, (to the Guitar Player) but sound muddy and garbled with less clarity and Musicality for the audience--as the Guitarist on stage cannot hear those high frequency cut-off, but the audience can and DOES!  What they are really achieving in truth.............is a more appealing audible stage sound, which is far different from that which is really being heard at distances!  Here is an example..............the typical Super Reverb amplifier owner, loves their vintage amplifier's 25-Watt 94dB rated speakers--Jensens usually.  The amp sounds lush, appealing and just right--while up close and ontop of it.  But at distances, what you more often hear, is predominantly mushy Bass Frequencies topped by Tube Clipping High Frequencies and speaker cut-off--Trebbles that are distorted.  The Musician on stage, thinks his sound is musically appealing, but many of those in the audience are cringing and thinking.............yuck............too much overdriven mush!  Now, take the same amplifier and change the 25 watt speakers with 40watt RMS and 100dB rated speakers, and step away from the amplifier--at lower volumes, you can produce more audible and appealing balanced frequencies, since the speakers are not being pushed into cut offs at higher Volumes.  And if you want controlled distortion, use a pedal effect which produces that distortion in the early stages of the pre-amp circuit which ironically..........happens to be the Tone Shaping Stage as well! 

In conclusion, here are some of my favorite speakers and the companies I think offer the best options and choices.  But, the choice is innevetible yours and some experimentation is an absolute.  Remember..................what you hear is NOT going to be exactly what someone else hears.  But, by sticking to the basics which will preserve your amp and your speaker's coils, you can have allot of fun while you experiment  So, good luck becoming a Legend.  Namaste!

Speaker Companies--our preferences in order of experiences:

1.  Eminence--without a doubt American made and offers the widest choices with the best prices--little known factoid.................back in the 60s, Eminence was outsourced to build the JBL line of D-110, 120 and 130s!  So, now you know the real origins of those great speakers still sought today!  Manufacturers do that all the time and it is common but not usually advertised to keep Brands separated.

A.  "Commonwealth"--this is the modern day "JBL" like speaker.  It has Aluminum Voice Coils and Dust Caps--4" big voice coil speaker!  This is the Grand Daddy of the 12" Eminence speaker lines, while maintaining very musical decible ratings.  This speaker is easily the most overlooked out there by the Twin Reverb guys due to we think...................its weight.  Huge magnets means only one thing--huge sounds that will never come from Voice Coils self destructing or cut off!  We love these speakers--they aint cheap, but oh my are they worth every penny!  For the Twin Reverb purists..............this speaker can play quiet with all the sensativity to the Guitar Player's nuances from picking styles.  But, when really pushed, the dBW is not so much so, that the speaker won't sound great with 6L6s Clipping and an A/B Amp's harmonics.......... wow.....................man.................just deadly gorgous! Big Aluminum forged baskets prevents deflection that occurs when any speaker is really pushed hard.  That deflection with stamped steel high powered speakers can cause Voice Coil vibrations that sound like Coil Rubs--called "Deflection".  Forged Aluminum baskets really are a must with high powered speakers.  Also, the Forged Aluminum basket helps stay true, when Baffle boards over-vibrate from poor mounting features or soft versus Hard wood construction.  This speaker's Coil Gap reminds me of the old JBLs and with the large Coil and other features the, Commonwealth is perfectly matched for moderate baffle boards--typical Plywood with top and bottom Baffle attachment screws.  Its huge magnets adds allot of weight also to the cabinet, which helps propell the sound out and away from the front of an amp--closed back guitar cabinets adds deflection/echo affects, but does not really do much to add to its Bass Frequencies!  Eminence really knew what what they were doing with this speaker!  We highly recommend them--if you can handle the added weight. 

B.  "Texas Heat"--150watts, stamped basket 99dB and for the Blues guys who are purists, but love that SRV or Texas-hot Blues with Hendrix feel and vibe, these speakers we have in another Twin we re-built here in the studio--fantastic absolute killer speakers!  The bottom end is tight, with incredible singing Mids and Highs.  These are my second favorites speaker for my Twins!  I get a chimey nuance that is just punchy but not mushy or soft sounding--very thumpy and tight with just a great blend of singing highs and sustains when pushed to 75% of thier capacity!  Why anyone would own a Twin Reverb and play anything else is a wonder other than...............

C.  "Swamp Thangs"--150watts at 102dB.  What I love about these speakers, is thier bullet proof damage proof coils--gaps are a bit wider than I like, but they offset the dB somewhat while increasing the RMS handling.  A 100watt Twin Reverb can just punish these things and they come back sounding sweeter and sweeter.  They don't have the singing highs like the Texas Heat, but they have that Mid Southern Rock grit with very tight and controllable Bass responses.  These were my favorites until the Texas Heat showed up!  I run 4-amps at one time in my set up--Two Twin Reverb Re-Builds, a Mooretone 100Watt Custom Amp and a Super Reverb we also completely re-built!  Reason for all the amps...............widened Frequency range at all three Frequencies which allows me to produce my sound from the stage so that the audience hears me and not the Sound Guy's interpretations.  I use the "Commonwealths" in my main Driver Amp, which are now in the Mooretone Custom Amp, and the "Swamp Thangs" in a re-built Twin which is set a bit more Bass heavy, while the "Texas Heats"  are in my other re-built Twin--which are used to produce a bit less Mids and High frequencies to those of the Commonwealths, but more than the Swamp Thangs.  The Super Reverb with Jensen 40watt Alnicos are used for Clipping and Background Distortion with modified circuit board to tame the High Frequencies that can produced icky sounding over-driven Highs that sound good to me up close, but can make my audience cringe!  I am thinking of selling this amp altogether though, as it really doesn't fit with what I am after--although a Twin style 100watt amp pushing a quad of 10 speakers might be interesting. 

2.  "Jensen Alnico"--25/40 watts each (10") 94-96dB and quite honestly, just moves beautiful amounts of air in my Super Reverb--the fourth amp in my line up.  I have to admit though.......................I am not a huge fan of thier other lines including the Mods.  Although, I did re-build a Twin Reverb (72 original rebuilt to 64 Blackface specs) and I used one Mod 12" Jensen with one 12" Swamp Thang" Eminence for a recording customer of ours.........................and the combination was just dead on perfect for recording--wow!  Both were in the 7.2 Ohms range so they were pretty well balanced and sounded great together.  Anyway..............................generally I don't advise mixing speaker brands due to the "nominal impedences" can vary enough, that one speaker runs a bit hot while the other may run hotter or cooler and usually you want fairly matched nominal impedences.  But once in a while you get a slightly worn coil that just happens to produced like impedences with another brand and if you are lucky enough to get those results, mixing and matching can be very useful.

3.  "Weber California"--I hear great things from other amp guys.  My personal experiences were okay--I found their 15" JBL like speaker, that a lot of people like in thier Vibroverb clones, to be just a tad bottom ended--very bass heavy and hard to keep clean.  But, that was also in an amp we did not build, and the same amp builder who built us a Twin Reverb from a 70s Silver Faced Amp (basic Black Face mods), used the Webers in that amp with the same mushy bottom end when pushed to 3/4 power or beyond.  So, it was most likely our amp builder who was at fault and not the speakers themselves--again, I hear a lot of people like them.

4.  "Peavey Scorpions"--I had an old set of 80s Scorpions in a 2x12 amp that was a "Classic" and I was fairly impressed.  The Peaveys took massive abuse and kept coming back for more.  In fact, I went through power output tubes several times due to how loud and hard I run my amps, and the Scorpions took the abuse without failure or damages.  Really, just great speakers perfectly matched to Peavey's PC circuitry which had the Overdrive via two 6L6 Output tubes--Solid state otherwise as well.  And oddly, for a lower ended amp with printed circuits it had a very well balanced sound through the Scorpions.  But, it was just not right for my set up, and instead I opted for another Twin from the 70s and found a lot more room for modifications than the Peavey amp offered.

5.  "JBL-D-Series"--Outsourced to Eminence (in various years of productions) back in its hay day...................what can you say?  A good lightly used set of vintage JBLs are just hard to find, but harder to let go, once you do find them.  We renovated a 64 Vibroverb for a customer, with a blown JBL, had it reconed and totally refurbished and it never sounded right or good after that.  We then found another lightly used one, on eBay and it was just perfect.  In fact we bought another one from the same Seller, and it went into one of our Mooretone Vibro-type amps (I built a couple of SRV Clones for myself) and since then, we have had a half dozen others come through the doors, and none sounded nearly as sweet as those other two.  Welcome to the vintage markets though......................you just never know what you're gonna get till you get it and play through it.  Overall--a vintage JBL is just hard to beat unless you buy the Eminence Commonwealths which are dead on identicle sounding to me.  But in a 2x12 cabinet.................you will need a forklift--forget carrying your amp anywhere.  But the trade off is well worth it for my set up and yours--if you want a singing Twin Reverb that has it all at all volumes. 

6.  "Celestion"--Greenbacks, Heritage and Classics......................well..............I guess the British and Marshall likes them.  I think they are underrated in terms of wattage, as they can get very loud for thier advertised ratings.  Again...................the dB rating would be the great moderator in that argument.  But, I find the Celestions, just not to my tastes.  In a Fender Blackface all tube amplifier like we build and 99% repair or upgrade.......................I find the Celestions tough to tame or really dial into the Blackface circuitry.  It's most likely me, as we've not been building amps long enough to really know all the great tricks of the trade--in fact, we know just enough to make our own mods work in conjuntion with our hand wound custom pickups and guitars and our customers love our amps--they are almost exclusively of the Blues crowd with SRV being the preferred Cat to imitate.  Studio warts and Sound Engineers, have every type of editing machine known to man, so I don't much care to build amps for those types.  I stick to the gigging guy who wants big sounds coming from the stage and not so much the mixer and re-mix speakers strewn everywhere.  But, if I were building amps for the recording guys, and didn't want to set up my amps in another room due to thier power..................I would probably opt for Celestions.  But, I don't think I would opt for them live or on stage, as when pushed, to me they sound very Brittish harsh.................not allot of bottom end--they sound a bit too bright and mid heavy with limited bass frequencies.