about those old MusicMaster Bass combo's

[popthree]

thinking about getting a MusicMaster bass amp....just how much clean headroom can you get with one? twice that of a champ or thereabouts?

if I picked one up, should I expect to have to replace the speaker? if so, with what?

[Raymond]

One of the guys who knows more about those combos is Rob DiStefano. He loves those amps and enjoy building cabs for the. He'll be more than happy to talk to you. Great guy. Give him a call.

[Andre']

Hey dude the MMB is the amp I love. I own 2 originals with 6V6 tubes and a custom one being buit by
Winfield Thomas http://www.winfieldamps.com./ - Finely crafted custom guitar tube amplifiers, called The Rosco. It will be able to take 6L6s anytime and that will give you about 25 watts for more head room. I would definetly recommend anyone that wants a simple small tube amp with versitality to get a Rosco. I will post sound clips when it arrives. I'm just very happy that I got Winnie to build me the amp of my dreams!!!!!!!!!!!!For a great price too.

[Rob DiStefano]

Originally Posted by popthree

thinking about getting a MusicMaster bass amp....just how much clean headroom can you get with one? twice that of a champ or thereabouts?

if I picked one up, should I expect to have to replace the speaker? if so, with what?

A stock MMB can have about 50% more volume and clean headroom than a stock Champ.

Both the MMB and Champ will be Greatly improved with a speaker change. I prefer using a Weber AlNiCo 12A125 with my main MMB - if you want more clean headroom, go with a quality ceramic 12" speaker (think: Weber 12F150). Definitely giggable un-mic'd for small venues, even with a heavy-handed chic drummer (ask me, I know about this all too well!).

IMO, the MMB is a GREAT bluez amp, and if approached properly it can work very well for other genres such as jazz and rock and even country.

It seems every time I espose about the virtues of an MMB the prices rise, so I wind up shooting myself in the foot. That's okay by me - it's good karma to spread the word and knowledge. Besides, our new Winfield "Rosco" amp will be like an MMB on steroids, in a very good way.

The Rosco proto amp #1 chassis has been completed, just awaiting the front and rear control face plates. It'll become a head amp and will initially power a 4x10 speaker cab loaded with Weber Sig10s AlNiCo's, but I'll also build a 1x12 cab loaded with a Weber 12A125.

Andre's Rosco amp will become a caged head amp that'll slide inside a 1x15 speaker/combo cab loaded with a massive Weber 15A150 AlNiCo. Interesting, huh? :)

As Andre' sez, we'll have some sound clips up ASAP, in a few weeks at best. Chassis pics to arrive shortly.

[yegbert]

What's "caged head amp" mean? Sounds like maybe it's in its own cabinet, but also fits cleanly inside a larger cabinet with the speaker?

[Rob DiStefano]

Originally Posted by yegbert

What's "caged head amp" mean? Sounds like maybe it's in its own cabinet, but also fits cleanly inside a larger cabinet with the speaker?

A metal protective cage, ala THD Uni-Valve ...

[popthree]

does the MBB push 8 ohm?

[telewacked]

Originally Posted by popthree

does the MBB push 8 ohm?

Yeppers....8 ohm into 1 12" speaker stock

[Rob DiStefano]

MMB info @ Fender Amp Field Guide ...

http://www.ampwares.com/ffg/musicmaster_bass.html

[popthree]

thanks everyone. good information.

[Raymond]

Originally Posted by Rob DiStefano

It seems every time I espose about the virtues of an MMB the prices rise, so I wind up shooting myself in the foot.

That's because you've bought almost every single one that was produced back then so there are only like 5 left in the market...

[Rob DiStefano]

Originally Posted by Raymond

That's because you've bought almost every single one that was produced back then so there are only like 5 left in the market...

Hey! I resemble that remark! :)

[radarman]

...... sounds like a very neat little "caged" combo. I like the idea of a cage and the amp mounted "tubes up". My champ gets plenty warm, and a MMB does too, with the tubes down and the chassis completely encased. I was thinking of modifying a Champ to aleveiate the heat in the chassis. Maybe some nicely painted and trimmed expanded metal strips on the top in front/back of handle. And some vent holes in the chassis back.

[popthree]

i should have bought a MMB a few months ago when i first started thinking about it...they WERE going for under 2 bills on ebay. here lately sellers are putting the opening bid @ 300. oh well...i'll keep watching...eventually one will go down cheap....or not.

[Rob DiStefano]

Originally Posted by popthree

i should have bought a MMB a few months ago when i first started thinking about it...they WERE going for under 2 bills on ebay. here lately sellers are putting the opening bid @ 300. oh well...i'll keep watching...eventually one will go down cheap....or not.

Yep. At a high of $200, you still hadda pay for a health check/caps, new tubes and the best speaker you could afford - which meant adding in another $75 to as much as $200. Not so cost effective at $300 for the stock amp.

[Rob DiStefano]

Originally Posted by radarman

...... sounds like a very neat little "caged" combo. I like the idea of a cage and the amp mounted "tubes up". My champ gets plenty warm, and a MMB does too, with the tubes down and the chassis completely encased. I was thinking of modifying a Champ to aleveiate the heat in the chassis. Maybe some nicely painted and trimmed expanded metal strips on the top in front/back of handle. And some vent holes in the chassis back.

I really don't think the amp heat issue is that much of a concern with an upside down chassis as long as the tubes and tranny's can breathe a bit. Better with a head as you can grille the front to allow air to pass from the front to the back and over the chassis.

Modding most Fender amp chassis' to go upside down will cause a control access problem due to the angled face plate. Some folks get around that by angling the chassis in the cab!

The Rosco amp has a totally squared-up chassis so it can can be used ala Fender or ala Marshall. And, it'll feature control face plates for either configuration!

[missfortune]

And was wondering if the baffle has enough room to put a 15 inch speaker in it (allowing for the widening of the hole, of course)? I'm thinking about an Eminence Legend 151. Any thoughts or suggestions?

If not, any suggestions for a 12 incher with lots of bottom end?

I'm playing an MIM Tele with a Vodka Mods modded Boss BD-2 for overdrive and a Tonebender MKII clone for fuzz.

I've read the archived posts here--there sure are a bunch of folks who seem to love these things, and know a ton about them. Thanks for the archived expert advice, and I'm hoping that an old MMB lover can enlighten me as to the possibility of modding for a larger speaker.

Thanks in advance!

[RussBert]

Originally Posted by missfortune

...any suggestions for a 12 incher with lots of bottom end?

Thanks in advance!

I have an EVM12L in mine. Lot's and lots of bottom end! My kid uses my MM to play bass on (go figure!) and the EV holds up well.

[Rob DiStefano]

Originally Posted by missfortune

And was wondering if the baffle has enough room to put a 15 inch speaker in it (allowing for the widening of the hole, of course)? I'm thinking about an Eminence Legend 151. Any thoughts or suggestions?

If not, any suggestions for a 12 incher with lots of bottom end?

I'm playing an MIM Tele with a Vodka Mods modded Boss BD-2 for overdrive and a Tonebender MKII clone for fuzz.

I've read the archived posts here--there sure are a bunch of folks who seem to love these things, and know a ton about them. Thanks for the archived expert advice, and I'm hoping that an old MMB lover can enlighten me as to the possibility of modding for a larger speaker.

Thanks in advance!

With baffle mods, you can stick a 15" speaker into an MMB combo cab. Here's an MMB cab I built to house a 15" speaker - notice how the baffle cleats are cut out to bridge over the sides of the speaker ...





... since my custom cab is the same width as a stock MMB cab (due to the 15" width of the chassis), you can achieve the same exact results with the stock cab - just make new hardwood cleats.

[Kingpin]

Rob, you build some sweet cabs! I love the wicker cane grill too. I start jonesing for one every time I see it, even though I need another amp like a hole in the head. :x

[Paul in Colorado]

Rob,
Couldn't you make a reversable faceplate printed on both sides, one side for tubes up and the other for tubes down?

[missfortune]

Thanks for the suggestions.

Rob, your cabinet is truly a thing of beauty! Very nice work.

Once my MMB arrives I'll decide whether to go 12 or 15 on the speaker. I can hardly wait! Hurry Mr. UPS man, hurry!

[Rob DiStefano]

Originally Posted by Paul in Colorado

Rob,
Couldn't you make a reversable faceplate printed on both sides, one side for tubes up and the other for tubes down?

I dunno about engraving both sides of the same plate - I guess it could be done. The key things to consider are: the chassis front must be veritcal (not slanted, ala Fender) and when you flip the chassis all the controls will be lined up in reverse.

[3StringGuitar]

If heat is really a problem couldn't you jsut get a small desk fan to set behind the amp. A friend suggested a computer fan mounted somewhere around the tubes. That custom wood cab with cane grill is flat out amazing looking especially with the silver face, sets it off very nicely!

[missfortune]

It's missfortune again...thanks for the speaker suggestions.

My MMB arrived last week in pretty good shape. Its an early 6AQ5 model. It sounded pretty nice with the original postage stamp magnet speaker, but today I dropped an Eminence Swamp Thang into the cabinet and now the MMB just roars! Seems nearly twice as loud at the same volume settings as before, and has lots of bottom end. Lovely, lovely, lovely.

I've got a feeling that I'm really going to like this amp.

[Rob DiStefano]

Good to hear of your fortune, missfortune! :D

[ravindave_3600]

Originally Posted by RussBert

I have an EVM12L in mine. Lot's and lots of bottom end! My kid uses my MM to play bass on (go figure!) and the EV holds up well.

I've had one for a few months and really enjoy it. I haven't changed the rather flabby speaker though, because I primarily use it as a home bass amp (imagine!) and then as a guitar amp, and don't know what speaker to put in that will serve. So - and mind you I know nothing about speakers - will the EVM12L stand up as a bass speaker? Or, the Swamp Thing? Senor DiStefano, any suggestions?

[3StringGuitar]

Well I posted this http://www.tdpri.com/viewtopic.php?t=42183 but it looks like most of the questions were answered here. I'm looking to get an MMB and get it down to just a head unit that will hopefully push my 4x10 cab. As I said in my other post I heard with a rebiasing you can change the 6V6's to 6L6's is that true? Also could someone explain teh difference between the later model's with 6AQ5's?

[Rob DiStefano]

Originally Posted by ravindave_3600

I've had one for a few months and really enjoy it. I haven't changed the rather flabby speaker though, because I primarily use it as a home bass amp (imagine!) and then as a guitar amp, and don't know what speaker to put in that will serve. So - and mind you I know nothing about speakers - will the EVM12L stand up as a bass speaker? Or, the Swamp Thing? Senor DiStefano, any suggestions?

I can only say the obvious - if yer gonna use the MMB for low end, get an appropriate speaker. Also understand that it's only pushing 12 watts at best ...

[Rob DiStefano]

Originally Posted by 3StringGuitar

Well I posted this http://www.tdpri.com/viewtopic.php?t=42183 but it looks like most of the questions were answered here. I'm looking to get an MMB and get it down to just a head unit that will hopefully push my 4x10 cab. As I said in my other post I heard with a rebiasing you can change the 6V6's to 6L6's is that true? Also could someone explain teh difference between the later model's with 6AQ5's?

It's the early '70-'73 (or so) MMB's that used the 6AQ5 nine pin power valve, and they're nothing like a 6BQ5 (EL84). IMO, the 6AQ5 is a good valve that'll provide righteous Fender tone, but it's not like a 6V6!

IMO, the MMB doesn't have the proper iron, or rectification, to handle a 6L6 valve. Do so at your amp's risk. Don't try to make a sow's ear into a silk purse! :) You want the ability to swap out 6V6 for 6L6, get yerself an amp made specifically for such a task, like the Rosco.

I'm in the process of building a head and 4x10 for a customer's MMB - it'll work out just fine! Using a quad of Weber Sig AlNiCo 10's.

[Tremo]

I know a guy with a MMB. He has the 6AQ5 model, and he put in an old Jensen P12Q that he got out of an organ. It sounds great. Plenty of volume.

[3StringGuitar]

Thanks for clearing that up. I don't know if I'll ever find an amp I can afford. "Durring the last 6 years of production of this amp 1976 - 1982 the only tubes that were used was the 6AQ5. every year up to 1976 used 6v6 tubes." This is what I had read online concering the tube change. Everyone I've talked to has said teh 6AQ5's are thiner sounding. I guess all I can do it try one out, unfortunatly no music stores around here have one. There is a nice Ampeg J12T for $300 though.

[Rob DiStefano]

Originally Posted by 3StringGuitar

Thanks for clearing that up. I don't know if I'll ever find an amp I can afford. "Durring the last 6 years of production of this amp 1976 - 1982 the only tubes that were used was the 6AQ5. every year up to 1976 used 6v6 tubes." This is what I had read online concering the tube change. Everyone I've talked to has said teh 6AQ5's are thiner sounding. I guess all I can do it try one out, unfortunatly no music stores around here have one. There is a nice Ampeg J12T for $300 though.

I dunno who said that about the MMB tubes, but FWIW I've had at least one stock MMB for every year of production, and I never found a 6AQ5 in one beyond '74.

Tone is subjective. 6AQ5's sound very fine and Fendery to my old ears - I just prefer an octal power valve, and 6V6 is *the* one I prefer in a small tube amp.

There will always be MMBs around for sale, keep looking, older PTP amps are gonna be yer very best value in terms of tone and dollars, in the long run - though the prices have risen in the last few years. $250-$300, for an MMB in good shape, is a fair price these dayze.

[Tremo]

I'd say, given my 'druthers, I'd go with a 6V6 version. But if the only thing that came along was a 6AQ5 version, I'd jump on that as well. The 6V6 and 6AQ5 have very similar transfer characteristics, and in those amps, sound nearly the same. Moreover, NOS 6AQ5s are cheap. But stock up, nobody makes them any more.

Whichever you get, have it capped and put in a good speaker like a P12Q or a Weber 12A125 or 12F125. Then just slap in some healthy tubes and you're good to go.

[Rob DiStefano]

3String - I heartily second Tremo's good advice!

[Jef]

Moreover, NOS 6AQ5s are cheap. But stock up, nobody makes them any more.

I had a nice MMB with 6aq5s for a few years (sold it...)and it saw some heavy abuse but those 6aq5s never failed. They're small (7-pin) but they have a big sound. The MMB sounded very similar to my 5E3 clone, but I liked the 5E3 better so I sold the MMB. I sure miss it, and I have a nice stock of 6aq5s in my drawer. They're only rated for 250V plate voltage so I think I'll use them for one of my next amp projects with that cheap power transformer that's just not potent enough to really satisfy the EL84s in my SS rectified 18watt project.

Jef[/code]

[3StringGuitar]

Yeah I've noticed I can't seem to find any 6AQ5's except the tube store and they just say “Assorted brands in stock" with no specifics. So would you all say the census is that I could easily play the MMB in a band setting, practice/gigs with out too much of a volume problem? I know most of the places I play mic anyways so I'm sure it shouldn’t' be too much of a problem but what about in a non-micd setting? I do know from using a PJ that that was loud enough to do shows and practice with. I wouldn't mind an old tweed PJ if I could find one in decent shape for a decent price, how much would you say a tweed PJ goes for? I’ve seen 350-450 for a few 94 ones.

[Rob DiStefano]

Also - you can mod a 6AQ5 MMB to take 6V6's ... I've had a couple like that, and they worked out just fine.

[missfortune]

Originally Posted by Rob DiStefano

Also - you can mod a 6AQ5 MMB to take 6V6's ... I've had a couple like that, and they worked out just fine.

Rob,

Can you point me toward the details of this mod? I'd like to keep this thing for a while and worry about the continued availability of the 6AQ5 tubes.

If I don't mod the amp for 6v6s, do the 6AQ5s need to be a "matched pair"? In my preliminary searches for these tubes I've been told that the only ones available are miscellaneous singles.

Many thanks for sharing your expertise!

[Rob DiStefano]

IMO, there are enuf good 6AQ5 bottles available to last for many decades to come - no worries.

Yes, though an MMB is cathode biased, you need to have the tubes matched - any good vendor tube source will do that for you, and you usually can even have'em matched hot or cool.

The Fender Amp Field Guide has a 6V6 MMB schematic - that's how the 6AQ5 can be modded ... this should be accomplished by a qualified amp tech only!