UNAD: Unexpected New Amp Day

[barrymclark]

This story has some roots stretching back to the very end of last year and the beginning of this one.

 

I was looking at either building an amp or repairing one. 212MavGuy sent me a PM saying he'd be willing to guide me in my journey and further informing me that my initial goals were a bit too ambitious and I should consider starting smaller. He pointed out what he thought would be a great project and I told him that I simply couldn't free the cash yet for it. So, he got it and then I bought it off him thereafter. It was very cool of him to be sure. Sadly, I had to come up with some extra money for some of the extra monies needed for buying a new home suitable for my daughters that have JRA (which we are within two weeks of closing. ), and I had to sell it. As charged as I was to jump on the project, I will admit equal amounts of being intimidated by it. I spent the past few months being very bummed about letting that project amp go.

 

Adding to it, I was just still not in love with the JC120. As good as it sounded, it just wasn't quite it. I got the point where I was going to put it up for sale but, with the house thing going on, selling it wasn't at the top of my list to do. Luckily, I haven't needed any more money for inspections. They are killing me with that crap. Anyways....

 

On July 4th, I had the opportunity to get out of the house alone and I figured I would wander the music shops just to have something to do.

 

The third store I went to had a Fender Excelsior. No offense to anyone who owns one, but I had written these off to be novelty pieces. I wanted to try one anyway mainly because I liked the simplicity of the controls and I am a sucker for that old cabinet styling.

 

A played for a few minutes and had a blast with the old school 'honk' this amp had. After a few minutes of playing some old swing and WAY early rock, I had a big grin and had lot of fun. I looked at my phone and my 'few minutes' was actually more like an hour and a half. I played a few more chords and melodies. This time it was actually a few more chords and melodies and not another hour and a half. I had found what I had been looking for: that SERIOUSLY old school jazz sound. What kills me is, I know I love the jazz and swing from the 40's yet I never really spent much time looking at amps either from that time or are replicas from that era.

 

I asked the salesman if he'd consider a Roland JC in trade. He said he would and I went home and rolled the JC out into the car. My wife says, "Do I even need to ask?". No... she didn't. She knew I was on yet another amp mission. I went into the store and traded. Just so you know, I all but stole that JC for the price I got it for. I actually made a couple of bucks.

 

Anyways, I got it home and easily played for hours on it. I did it again the next day... and the next.

 

Normally, I just play my hollows acoustically as I don't want ot bother with plugging in an amp and so on. Even when they are new. This wasn't the case with the Excelsior. I gladly go out of my way to pull the amp out from the wall, plug it in, plug the guitar in and play.

 

First, this amp isn't going to have mass appeal stock. Not even a little.

 

That being said, these are my impressions after maybe 12 hours of play:

 

• The amp is no paperweight. It is right around 33 pounds or so. About the same as my Cube 80x. Most of that is MDF. If the cab was pine, I believe it would be just under 30 lbs.
• It is kinda large but not overbearingly so.
• At start, the bass was very lacking but as the speaker breaks in, I am hearing a fuller bass coming in.
• VERY unforgiving. If you don't have your picking dynamics under control, you are going to poke someone's eye out. You may need to adjust your playing technique for the amp. I did.
• The upper mids are VERY pronounced.
• The tone is controlled by a slider switch. You have a Dark and Bright setting.
• The amp also has a built in Trem effect. I have never been fond of this effect, but this one is VERY musical.
• The amp starts to get gritty early on the dial... especially with humbucker but rolling off the guitar volume helps keep it somewhat clean.
• No reverb.... and I don't even miss it. The amp has this enveloping tone that just negates the need for it my ears.

 

I am getting a tone similar to what you hear from Dave Barbour in this video:

 

http://www.youtube.com/watch?v=nThquNN4J4E

 

Where this leaves me is with the understanding that type of amps that works for me is the back in the early days of guitar amplification.

 

How does the story of the project amp fit into this?

 

Well, as much as I dig this amp, I have identified some areas that I want to work on with this amp.

• The tone slider: I don't mind where the extremes are with this, but you get nothing in between. I am replacing the slider with a pot. Easy modification.
• The speaker: not sure yet if I will change this out or not. I am waiting for the speaker to get broken in. If, after a week or more of the continued playing that I have done thus far, I am still not satisfied with the bottom end (and I am not far from being satisfied as it sits) then I will look at either a Weber 15a125a or a 15a125.
• The tubes will get replaced with better of the same type but the V1 will get a lower gain tube. I will back off the 12AX7 and slowly work down trying out a 5751, 12au7 and so on.
• I hear the iron in these do benefit, not greatly, but do benefit from something more solid such as Heyboer, Classictone or MM or the like.

 

The tie in is, I am not giving up on amp modifications and this amp presents a perfect opportunity for me to get my feet wet with it.

 

There is another amp sale/purchase brewing and I will let all in once it all actually happens.

 

212mav, sorry I had to let that amp go, but if it is any consolation to you, the spirit is still going and the tone knob parts (pot and knobs) on their way now.

 

 

 

[212Mavguy]

Awww, Barry!

 

What wonderful affirmation you have given me, I'm tremendously honored!

 

One of Central California's premium harp players, Jeffrey Halleck uses, gigs with and loves his Excelsior. He got it after selling his Mesa Lone Star Special, a VERY nice sounding modern American production amp.

 

On the speaker...in my humblest opinion forget those small voice coil 15's from Weber. The size of the 15 inch cone demands a voice coil that can provide far more cone control as a rule than a 12 inch speaker. On eBay there is a seller that sells NOS JBL MI-15's for 109 plus shipping. He'll bite for an offer over a hundy, probably. I have two of them and they are absolutely amazng guitar speakers clean, but the dirty tones are even better, smooth, tones very similar at moderate or loud gig master volume settings. Also, at 102db 1w 1 meter they will provide more headroom than some 15 inch speakers will. Think the VC is 2 1/4 inch, and know it's assembled with milled flat wire wound to put more copper in the VC gap. The voice this speaker privides is what the amp is putting out, a flat freq resonse was a design goal. These go 45-6000 hz if I remember the specs right. Presentation is warmer than a D130 and much nicer when playing in the dirt. Paper dust cap on the JBL MI series. I have two and I'd sell the broken in or unused one for my cost if eBay is not the way for ya.

[barrymclark]

Hey Mav. The affirmation is well deserved.

 

I had honestly looked at the JBL (due to our earlier discussions) and my concerns were two: it is MUCH different than what I would be pulling out tonally and, from the pictures, I am not sure it would fit physically. I really don't want to change the the sound of the speaker too much. I do like it. I'd like only slightly fuller bass and any other differences to be very, very negligible. I kinda dig the 'crappiness' if that makes sense. haha. The clearances in the back are very tight. As few 'guitar' 15" speakers exist, even fewer will fit in there without hitting the tubes or conduit. From what I read on BillM's site, he said the Emi Legen 1518 'just' goes in with the pre-tubes perfectly straddling the magnet. The Eminence has a basket that angles in whereas the JBL basket angles out more and very likely hits the tubes/conduit. I can't tell the back to front dimensions but I only have 7.5" from the back of baffle to the edge of the back of cabinet potentially being another fit issue. The speaker is rear-loaded.

 

The reason I looked at the Weber is that it appeared to be the closest I could find in modern production (within a reasonable price) to what is already in there that would open up the bass a bit more but not stray too far from the tone I already dig from the stock. There's the P15N... but man they are NOT giving those guys away. haha. There's also the C15N but I am a fan of AlNiCo smoothness. It is at least in the same price range as the Webers.

[212Mavguy]

The JBL will be fuller and tighter on the bottom end and won't ever go to mush. It will do the jazz thang extremely well, you'll be turning down that tone killing bass knob a notch or two more than the Jensen or Weber. I'd be surprised if it was as dimensionally deep as the Jensen alnico frame and cone is. Jensen style cones are steep flat sides and deep, the JBL is parabolic. I've been known to redrill and re-t-nut holes around the cutout to shoehorn a Peavey 10 inch scorpion into a Silverface Champ combo that had cast frame spoke clearance issues with the can cap...only to later yank that speaker as unsuitable for that amp design. I understand your caution about the JBL frame.

 

I do have a pair of vintage original paper P15n's in great shape sitting unused in the basement...also a pair of well doped Magnavox p232 15's, a less expensive version of that speaker but better build. They are great guitar speakers in sound, but the JBL has an open sounding musicality in the all important mids voice that these just can't match. You won't miss rattiness or loose bottom end, or a speaker imposing it's own tone limitations on the amp. I won't be using them for me anymore, I got ruined by Altec and JBL products or recones using them as the base. If you can get hold of a vintage 15 original paper Jensen Vibranto, it will do exactly what you want and fit perfectly without the bell cover on it. It is a very warm and full sounding ceramic speaker, I prefer it's tones to the alnico's earlier mentioned, and I'm a huge alnico fan.

 

Glad that you have an amp platform that you are excited about! Keep bumping this one as the parts come in...

[barrymclark]

Hey Mav. Here is the clearance issue.

 

 

The next concern with the JBL, as is with the Legend 1518 is the weight. The Legend will definitely pull the overall weight of the amp up about 10 lbs putting it in the low to mid 40s. I'd definitely like to keep the weight down. The P15N is probably the most direct replacement.

 

You could probably get some coin for those Jensens! The price of those guys new or used has kept me away from the Jensen P15N. If they were down lower, I'd definitely look at those. Over the JBL and Eminence, I'd be giving up sensitivity for sure. I've hung up my group playing aspirations for good. I just need an amp combo to clear the acoustic sound of my guitar now.

 

I will definitely keep this thread properly bumped.

[212Mavguy]

Yep, I figger 350 for the pair of p15n is about mid market. The Maggies I'd turn loose for 35 bucks each, not collectible due to me boogering the cone surround with damping material to roll off some high end freq's... Don't see any problem shoehorning that JBL in there from looking at the pic to be honest, the magnet is about the same diameter as the stock one. I have a Jensen concert 15 from my Harmony 420 and can compare frame depths with that JBL.

[barrymclark]

Yep, I figger 350 for the pair of p15n is about mid market. The Maggies I'd turn loose for 35 bucks each, not collectible due to me boogering the cone surround with damping material to roll off some high end freq's... Don't see any problem shoehorning that JBL in there from looking at the pic to be honest, the magnet is about the same diameter as the stock one. I have a Jensen concert 15 from my Harmony 420 and can compare frame depths with that JBL.

Actually, I just found another picture of one that was more of a side shot showing the frame profile a bit better. You're right. That may just clear. If that eBay guy has a return policy, I may just try one.

 

Found a spec that has the net weight at 7 lbs. Perfect there.

[DetroitBlues]

I had an excelsior for a while. It was an amp I just didn't need. Sounded great, had its own unique voice. You're right though, it needs a tone knob, not a switch.....

[barrymclark]

I had an excelsior for a while. It was an amp I just didn't need. Sounded great, had its own unique voice. You're right though, it needs a tone knob, not a switch.....

Absolutely. Regardless of anything else, that is a mod that is going to happen.

[212Mavguy]

You might want to investigate how Carr amps does their voicing switches on their amps. What is used is not a variable resistor, which is what a pot is. introducing such a part in the circuit may or may not cause some unforeseen outcomes. A multi position rotary switch with different cap values across the terminals will do the same as the slide switch but offer several alternatives, and also for ease of doing...might be easier to follow the native type/style of tonestack/controls when doing the mod. My Ceriatone SSS uses a 7 position knob to control the inductor portion of the circuit's tones. The jump between values can be mitigated with the instrument tone knobs if it has 'em.

[barrymclark]

You might want to investigate how Carr amps does their voicing switches on their amps. What is used is not a variable resistor, which is what a pot is. introducing such a part in the circuit may or may not cause some unforeseen outcomes. A multi position rotary switch with different cap values across the terminals will do the same as the slide switch but offer several alternatives, and also for ease of doing...might be easier to follow the native type/style of tonestack/controls when doing the mod. My Ceriatone SSS uses a 7 position knob to control the inductor portion of the circuit's tones. The jump between values can be mitigated with the instrument tone knobs if it has 'em.

Luckily, this has already been done by a number of people (such as BillM) and seems to be issue free.

[212Mavguy]

Schweet! Get after it.

[barrymclark]

Schweet! Get after it.

If I can scratch the funds together, I may get that JBL just to have it around even if it doesn't somehow fit the Excy. Would be a good basis for another project at a minimum.

 

Only 4 left though. Booo!

[DetroitBlues]

Honesty, you won't need the speaker upgrade.... Just break that one in... Play it for a while, it will sound better and better...

[barrymclark]

Honesty, you won't need the speaker upgrade.... Just break that one in... Play it for a while, it will sound better and better...

I have put in probably 16 hours on it so far. The bass is coming in... but I am not sure if it will come in much more. I am waiting to see though. I am not expecting bottom end like my Cube but just something a little more solid. If that comes in, I will be happy.

[barrymclark]

I have put in probably 16 hours on it so far. The bass is coming in... but I am not sure if it will come in much more. I am waiting to see though. I am not expecting bottom end like my Cube but just something a little more solid. If that comes in, I will be happy.

I take that back. From reading up on this type of speaker and the length of time it takes to break in for my approach I may only be a quartet the way there. Oh well, I'm getting there.

[barrymclark]

Played my electric upright bass through the Excy last night... and it sounded as top notch as it gets. I plugged it in to really get the speaker moving for a bit... and because curiosity got the best of me. Upright tone for days. Plenty of bottom at least for that.

 

I did this after running my mp3 player through the Excy for a bit to get the speaker moving while listening to music during chores. I noticed how much bass was coming through. So... yeah. The music sounded really good until I hit roughly 75% of the dial. Then it started turning into a overdriven hot mess. Brian Setzer, Ray Charles, Wes Montgomery all sounded great.

 

Got me thinking of long term mod goals for it.

[DetroitBlues]

There you go... good news is, if the circuit goes out on it, the amp itself has a lot of space to build into....

[212Mavguy]

Haw! So true! You never know what can happen around here...the enabler factor!