I recently bought a Masco MA-17 and would like to build a 4x8 cab for it, and I must say, I know nothing abut cabs and speakers.
I understand the amp has 2,4,8,and 16 ohm speaker taps, and that it is 17 watts. Also from what I have read in the forum, Weber speakers would be a good choice (either Signature or Vintage, smooth or ribbed, ceramic or alnico).
The question is, how should I put all of this together? that is, 4,8 or 16 ohms speakers? wattage? wired in serial or parallel? .....how to do all of the math??
As long as the amp has those taps,it doesn't matter. Stick with speakers of the same ohms,don't mix a 4 with an 8,for instance. Series wired ohms just add--2 8 ohms in series gives you a 16 ohm load. Parallel wired,as long as the ohms of the speakers are all the same: 4 16 ohms speakers wired in Parallel= 16/4--4 ohms. 2 8 ohms in parallel 8/2=4 ohms. 4 8 ohms 8/4=2 ohms. You can use a combination of series and parallel wiring to get different ohm loads,but that may be getting a bit too complicated for you.
@jaimekike,.. Everthing ya need to know about speakers is right here for ya ,..all the tips an tricks,. Let's Talk Speakers :\ http://www.webervst.com/sptalk.html ---------- Simply Unique Kustom Mic's By Rharley
Yes ,..I Think I posted a thread a while ago of that site,. maybe should start a thread<>?
I believe one question asked was close to what jaimekike wanted to Know with out doing all of the math??:
I have two 8 Ohm speakers that I can wire either parallel or series to my tube amp for an impedance of either 4 or 16 Ohm. My amp has both 4 and 16 Ohm output taps. Are there any sonic differences or benefits of series over parallel wiring or vice versa? ---------- Simply Unique Kustom Mic's By Rharley
Last Edited by on Dec 26, 2010 3:43 PM
I have a speaker cab with 2 8ohm ceramic speakers, a 10" Jensen and 12" Weber. I have used this cab with two different 2-6L6 PA heads, one a Stromberg-Carlson AU-57, and one a Knight KN-3245. I have found that using the speakers in parallel and the 4ohm tap I can get more volume before feedback than with series and the 16ohm tap. I can't say that I have heard sonic differences or that this specific case can be generalized to all amps/speaker cabs. But that is the way it works with these PA heads and this cab.
By far the most common speakers are 8 ohm, and the most common way to wire 4 8 ohm speakers is in "series parallel" - that is, wire 2 pairs of speakers, each in series, making 16 ohms for each pair, and then wire the two pairs in parallel, making the set of 4 come out to 8 ohms.
If I was going for 4x8 with an amp that had 2,4,8 & 16 ohm taps, I'd use 8 ohm speakers and try all 4 in parallel for a load of 2 ohms to start with. They could also be wired series parallel as Greg suggests, for 8 ohms, which may be more useful if the OP is intending to use the cab with other amps.
In the past I did run an amp with 4 Valve Junior speakers (sig 8 clones) wired in series parallel at 4 ohms. The biggest problem with it was lack of projection, sounded nice on stage but not as loud or able to project as 2x10 in parallel.
I have done this with a Masco ME 27 it had 4x8" modern Jensens (Webers would of been much better) with four 8 ohm speakers I would run the amp at 4ohm.
I also had a Masco MA 25 & a cab with 12" & two 8's I think the the 12" speaker & two 8's was a better option than four 8's.
I also ran the Masco MA 25 with a 100 watt alnico & a kinder feedback pedal & the sound was incredible very loud fat tone & raspy
Thank you all for the valuable information. I will be building a 4x8", with Weber smooth cone Alnico Signature 8 ohm speakers in parallel for a 2 ohm load, in an 18.5 x 18.5 x 7 inch black british stile cab, open back, with BluesBraker grill cloth.
I will post pictures as it is done. Thank you for the comments.
Note: the 8a100 Vintage Series are very tempting with the H dust-caps, but tooooo expensive, twice the Alnicos!!
Yes, the Vintage Series speakers are expensive, but they sure sound great!
I don't know where you are planning on playing this thing, but I can tell you from experience that while the tone out of an MA-17 is amazing, it is seriously lacking in the volume department. I don't believe that 4x8 will get you enough output to play with a modern blues band.
You could probably build a 2x8 cab and use the extra cash for a microphone to amplify the setup.
Here is how an MA-17 sounds through a 2x8 set of smooth cone Alnico Signatures.
I took this setup to a blues jam. It was almost immediately drown out. I plugged the speakers back into the Harpgear Double Trouble head and could be heard.
