HawkeyeKane
564 posts
Dec 21, 2011
7:37 AM
|
I was browsing around yesterday, trying to see if I could find a classic Kalamazoo logo graphic to make a sticker out of. Came across this instead.
The site is VERY vague, and I have yet to hear back from the address to which I wrote. I even wrote Greg to see if he'd heard about this guy. He hadn't, but he did find out that this guy has indeed secured the trademark to the name. Very interesting if you ask me. Though I'm not wild about the look of the new cabinet, the setup is pretty neat. Especially what seems to be the ability to take the amp out and make it a head/cab. Has anyone else seen this or had an experience yet?
Kalamazoo ® Hand Built Vintage Style Tube Amps
----------
Hawkeye Kane
|
Greg Heumann
1383 posts
Dec 21, 2011
9:06 AM
|
I don't kow if it is neat or not. Note this is NOT the original Kalamazoo circuit - he is (at a minimum) using a solid state rectifier. There may be other differences as well. Given that power supply sag is a HUGE part of the Kalamazoo's characteristic tone, this is a Kalamazoo in name only.
/Greg
|
HawkeyeKane
566 posts
Dec 21, 2011
11:39 AM
|
Well...these days it's kinda hard to duplicate the original circuit since the rectifying 6X4 the 'Zoo and a few other amps in its class used is now out of production. It's weird though, the Reverb 12 used recitifying diodes at the same time the One and Two were using tubes.
I dunno Greg. When that guy writes me back, I'll let you know what I find out. And when I said neat, I really just meant the idea of making it convertible between combo and head/cab. The rest of it I can take or leave. Especially the Kalamazoo marquee he's using. Call me old fashioned, but I'll always prefer a blue Chevrolet bowtie to a gold one.
----------
Hawkeye Kane
|
MJ
340 posts
Dec 21, 2011
12:06 PM
|
6x4 tubes are still available without much trouble or expense.
|
HawkeyeKane
567 posts
Dec 21, 2011
12:13 PM
|
Available, yes. They're still out there. But for the guy to get them on a regular basis for production, that might get time and cost consuming.
----------
Hawkeye Kane
|
chromaticblues
1103 posts
Dec 21, 2011
12:14 PM
|
Nothing about this says Kalamazoo. This looks like another bad 50's reproduction.
|
HawkeyeKane
568 posts
Dec 21, 2011
12:24 PM
|
I don't even think that's a 10" speaker in there!
----------
Hawkeye Kane
|
LSC
124 posts
Dec 21, 2011
7:22 PM
|
"This looks like another bad 50's reproduction."
Can't judge a book by looking at the cover.
"I don't even think that's a 10" speaker in there!"
Looks like an 8". Hmm, Champs use an 8". Does that make a Champ a bad amp?
I know nothing about this amp other than what we've all seen here and what is on their web site, which isn't much. It does seem like negative conclusions are being drawn and equally negative judgements based on scant evidence. I don't think the guy is trying to do a Zoo repro anymore than the Sonny Jr Avenger is trying to be a Bassman repro. This amp might be crap or it might be great. In either event, perhaps we can hold off on lobbing grenades until somebody actually plays through the thing. Just saying.
----------
LSC
Last Edited by on Dec 21, 2011 7:24 PM
|
HawkeyeKane
569 posts
Dec 21, 2011
8:32 PM
|
No pinless pineapples here LSC. But I think the skepticism conveyed is relatively justified. He's calling it the Kalamazoo Model 1, a well respected name in the harp player world. And from what we can tell so far, the components he's using are not what one would expect or desire in an amp bearing that name. And no, the Champ is by no means a bad amp. But the original 'Zoos used a 10" Alnico.
----------
Hawkeye Kane
Last Edited by on Dec 29, 2011 6:56 AM
|
MP
1931 posts
Dec 22, 2011
1:41 PM
|
i think it's pretty. i'm sure my model one is better but this amp might sound kinda cool.
----------
MP
doctor of semiotics and reed replacement.
"making the world a better place, one harmonica at a time"
|
Greg Heumann
1385 posts
Dec 22, 2011
6:54 PM
|
One two three
I completely agree
with LSC
to the punch, he beat me.
----------
/Greg
|
Joe_L
1678 posts
Dec 22, 2011
7:27 PM
|
Greg - you are very poetic today.
A couple of years ago, I dropped off a few amps at David Barrett's Master class for his amp shootout that's featured on his website.
There was a guy there that said he had bought the Kalamazoo name. He was building new amps. I had his card, but I lost it. I don't remember his name. I remember him saying it wasn't a reissue of the old amp. I don't remember what the amp sounded like. It might not even be the same guy.
----------
The Blues Photo Gallery
Last Edited by on Dec 22, 2011 7:34 PM
|
Willspear
15 posts
Dec 22, 2011
8:56 PM
|
Doesn't lookbad but the last thing I'm after is another el84 toting amp.
Also I like 8 inch speakers no problem there if that is in fact 8 inch
|
HawkeyeKane
571 posts
Dec 23, 2011
6:20 AM
|
@Joe_L
I would imagine it'd have to be the same fella. Kalamazoo's not a name that gets applied to many things.
Anyways, I wrote the email on the webpage and told him I'm an owner of a '65 Model Two and asked him if he had any intention of developing his line further to include the Deuce or the R-12. Still waiting for a response.
----------
Hawkeye Kane
|
HawkeyeKane
579 posts
Dec 28, 2011
6:10 PM
|
I've established a correspondence with Kalamazoo Joe Goforth.
ME: I have a couple of other questions for you though. First, on your Model One...is the setup convertible between the combo and the head/cab configurations? Or is it strictly choose one configuration at purchase and that's the way she comes?
JOE: The Kalamazoo 1 is a modular design so the head can be removed from the box as in the pics on the web site. I would like to generate some interest in the Kalamazoo amplifier brand. I've had thoughts of providing kits in various forms. What do you think of that idea?
ME: By kits you mean amp kits for enthusiasts to assemble themselves?
JOE: Yes.
ME: Since I only see two tubes on the amphead, I can only assume you're using a solid state diode for rectification. Can I ask what factored in your decision on that? I realize that the 6X4 is no longer in production, so that'd be out of the question in terms of meeting production en masse. But what about something like a 5Y3 that have been used in amps in the same category as the old 'Zoos?
JOE: The sag from a rectifier tube can be simulated with a series resistor. I've considered the rectifier tube as an option though. It uses less power with the diode though.
ME: Is the speaker in the photos an 8" Jensen?
JOE: Yes.
ME: Are you planning to keep your line strictly with Model One or do you plan to reissue the other Kalamazoo models?
JOE: My work with the amplifiers is based on the interest shown in them. I would like to avoid having them made in China.
----------
Hawkeye Kane
|
arnenym
24 posts
Dec 29, 2011
9:13 AM
|
In fact a rect tube could be simulated with resistors as Ted Weber does in the copper caps. I just burned my second power transforme caused by a bad rect tube.
I have changed my rect tubes to diodes and resistors or copper caps in all my amps now.. They are reliable and have no rattling.. And you can get the sag you want. But a K-zoo is a Class A amp and they dont have any sag at all.
The typical K-zoo sound came from a 12Ax7 and EL84 and they do not have bypass caps on the cathodes. Voltages and type of tubes is more important than rectifier. I made a k-zoo modification on a Valve junior once and compared it to a (recapped) original k-zoo 1. We recorded it. It was almost no difference between them. Even if we had different speakers. He had a original speaker and i had a Jensen 8 alnico.
Edit. Many ss rect amps have higher values on filter caps. This is more important for the sag-sound than the rectifier.
Last Edited by on Dec 29, 2011 10:30 AM
|
Pluto
197 posts
Dec 29, 2011
12:10 PM
|
Class A amps have no sag????? My zoo sags for days. Its the greatest 5 watt amp on the planet (imho)and its because of the tube rectifier and 10" speaker.
|
arnenym
25 posts
Dec 29, 2011
4:14 PM
|
Pluto. Nope. It's because they don't have bypass caps.
|
Greg Heumann
1397 posts
Dec 29, 2011
5:19 PM
|
I am still not clear on whether the circuit is in fact a copy of a Kalamazoo circuit at all - or simply a typical 5W amp? The amp looks more like the Kalamazoo's of the 50's that preceded the Model 1 and Model 2.
@arenym - I know in theory a class A amp doesn't have power supply sag. But I don't understand why, just because it doesn't have bypass caps, it shouldn't have power supply sag. I assume that more current MUST be drawn to amplify a larger signal than a smaller one. There's only so much current available - more in an initial burst as the filter caps can supply it - and then the voltage sags. I've watched all the lines of a Kalamazoo on an oscilloscope and there's no doubt in my mind that there IS power supply sag. This is why using much larger filter caps tends to reduce the amp's natural distortion. I am not an analog engineer - you have more knowledge in theory and operation of tube amps than I do - so I can't explain why - but I can tell you there's SOMETHING going on.. I have also tried copper can rectifiers in my Sonny Jr amps - and I swear they sound harsher. I switched back to tube rectifiers.
----------
/Greg
Last Edited by on Dec 29, 2011 8:09 PM
|
Mojokane
488 posts
Dec 29, 2011
8:32 PM
|
sag?
how much, how much?
not that I'd buy one...but I might!...
I just had some work done on my Kalamazoo Model One and Sanoette. Both nearly identical in circuitry. The Sano had ceramic discs everywhere. They were replaced with Mojotone mustard caps. To soften the harshness, I'm told. Both the Sano and Zoo Model One sound pretty damn good. You just can't go wrong with a Kalamazoo Model One.
Recap it, upgrade the speaker, three prong cord, maybe a new cab, some tweed, and why mess around with something which is already near perfect.
Finally, someone who is doing it! Awesome, Joe.
I really got a thrill out of the "Goforth" Model One.
How much?
I'll check out the site...thanks.
----------
Why is it that we all just can't get along?<
Last Edited by on Dec 29, 2011 8:36 PM
|
arnenym
26 posts
Dec 30, 2011
4:28 AM
|
Hi Greg.
I know how it sounds - It sound as a Push-pull sag.
You get the same effect with a ss rect and resistors.
It's hard to try to explain this because i have not english as first language. I do not go in yo discussion about Amp-classes. And i believe you can ask any amp tech you know about this and get a better axplanation then i can give you on broken english.
The current can not get to the tubes fast enough. They want more. It gives compression. That's sag.
If you take a Valve Junior and cut out /change resistors to k-zoo values, adjust the currents to Kalamazoo level, go down a little on filter caps value, and cut out the bypass caps. you get the same "sag" Compression. Without rectifier tube. Don't ask me why.. But maybe this discussion belongs in another forum?
Last Edited by on Dec 30, 2011 4:31 AM
|
HawkeyeKane
585 posts
Dec 30, 2011
6:26 AM
|
@Mojokane
The price isn't listed on the site. You have to inquire by email. I haven't really asked Joe about that detail because at this point I don't think I'll be getting one.
I will say this for Joe though, he's being very amicable and reasonable with his trademark rights. My wife and I are trying to start fabricating a small line of gig-bag type carrying cases to fit the vintage 'Zoo Models 1 through 4. We want to embroider the old Kalamazoo logo on them. He's only asking a very minute royalty for the simple reason of protecting the trademark and name.
----------
Hawkeye Kane
Last Edited by on Dec 30, 2011 6:36 AM
|
KingBiscuit
141 posts
Dec 30, 2011
6:53 AM
|
@Greg - In your last post on this topic, you mentioned that you don't use copper can rectifiers in your Sony Jr. amps...does that include the Avenger? My avenger came with the copper can. Reading Gary's web site, he indicates that he tried a lot of different tubes and the copper can won out.
I will probably leave my Avenger as it is, but I'm curious if you found enough benefit to warrant swapping it out and what did you replace it with. If there was a swap, did you have to tweak anything or was it just pull the old tube and put the new one in?
Thanks,
Dan
Last Edited by on Dec 30, 2011 6:54 AM
|
Greg Heumann
1400 posts
Dec 30, 2011
8:38 AM
|
@King - mine came with tube rectifier. I could be blowing smoke because honestly I trust Gary's ears more than mine - but I prefer the tube. If you switch rectifiers they may have slightly different output voltages so the power tubes should be re-biased to the same current for a fair comparison.
----------
/Greg
|
KingBiscuit
142 posts
Dec 30, 2011
10:39 AM
|
@Greg - Thanks....I'm in the "if it ain't broke, don't fix it" camp. That being said, my Avenger is fantastic so unless some major turn of events comes about, it will always have the copper can. Thanks again for the info.
|
5F6H
1050 posts
Dec 30, 2011
10:47 AM
|
@Greg & Arnenym...
Class A amps theoretically don't sag, *if* centre biased & *within their rated clean power output*, under drive/distortion, as most folk play them, they sag...It's a bit like knowing objects fall at the same rate in a vacuum, interesting to know but of little practical use in everyday life! ;-)
Most single-ended instrument amps usually qualify as "class A" simply by virtue of only having one power tube (therefore can't switch to AB, as there's no out-of-phase tube to take over the other half of the wave), rather than being designed to meet perfect "class A" operation criteria.
This is a much misunderstood area & Randall Aiken's thoughts on class A are much misquoted. His piece on class A bias & sag also relates to push-pull amps in the main.
www.myspace.com/markburness
|
Greg Heumann
1401 posts
Dec 30, 2011
11:15 AM
|
Thanks, Mark
I hate it when my own observations conflict with "theory" so it is nice to have an explanation that rationalizes them.
----------
/Greg
|
MJ
341 posts
Dec 30, 2011
11:15 AM
|
Greg, what type of rectifier tube do you run in your sonny jr. ?
|
arnenym
27 posts
Jan 01, 2012
7:08 AM
|
Okay. I do not disagree Mark. When I made those modifications and wrote in the forums on Sag in my VJR I was yelled at by everyone.
What sounds sag in an SE amp was something else, did all of them told me, all the time.
Anyway, you can get the same effect (sag) with diode rectifiers and resistors.
Add a 5W and 100 - 150 ohm resistor between the CT and the plate and You have the same effect.
Happy new year...
Last Edited by on Jan 01, 2012 7:09 AM
|
