#1
Inspired by threads on this and other fora I bought a Fender Champion 600 - now only available second hand but the internally identical Gretsch G5222 can still be bought new.

A great little amp with oodles of tone despite just having a volume knob. I also have a Bugera V5 which, despite being armed with 4 knobs, doesn't hit the pleasing tones of the little Fender as readily. I also like the diminutive proportions of the Fender. The Bugera is by no means large but looks bloated in comparison.

Unfortunately, because of power supplies in the UK not really being the same as the rest of Europe the Fender hums when plugged into a UK wall socket. It was this that mainly prompted my first mod, although I had bought the amp with the intention of moding it. It was the hum which really tipped me over the balance.

I bought a kit from Alnicomagnet on ebay and the supplied instructions where extensive and faultless and to be recommended.

Areas addressed included:-

Hum - Components to create a filter and voltage modifier are added together with repositioning the output transformer.

Tone stack - Mods to the tone stack are widely documented and demonstrated elsewhere but having all the high quality components in one kit made things much simpler.

Triode/Pentode switch - Moding the tone stack makes the amp a great deal louder. Fitting the triode switch helps tame it for late night noodeling.

Standby switch - The original 50's Champ had a tube rectifier, because this new beasts rectifier is solid state the initial power to the amp tube is instant rather than ramping up as it did "back in the day". This is detrimental to the tube and can be solved by fitting a standby switch. This was also combined with an additional slow blow fuse.

5E1/5F1 Switch - A simple switch in the circuit to cap C3 gives two alternate voicings, perhaps like a brigtness or treble boost switch.

Speaker - Separate to the Alnocomagnet described mods I fitted an 8" speaker in lieu of the original 6. It is a squeeze and requires a replacement speaker baffle and new speaker cloth but does fit. I'm not happy with the current speaker choice (4 ohm speakers aren't readily available in the UK) as the currently loaded speaker is over rated at 30-120 max watts so is a bit lethargic and darker sounding than would be ideal.

All in all great fun, very satisfying, relatively cheap (even after all of the mods) and produces a killer late night sofa side table amp. To be recommended.

My late night sofa side table amp

So what next?

A better 8" speaker, nothing else left to do....Although... As per the picture I have a second currently un modified 600. I bough this to reference the changes to the original. Having found pictures of the original 1950's Champ upon which Fender based the 600 I have a fancy to reproduce the internals of the original. I may use an eyelet board rather than the copper backing plate of the original, as this has the potential to be a little dangerous, but otherwise.
Last edited by John Sims at Feb 16, 2015,
#2
Looks to me like the G5222 is no longer available in the States. Musician's Friend is showing it as no longer available. Went to the Gretsch website, which recommends Cream City Music in Wisconsin as an online dealer, but it's not showing up on their website either. Amazon still seems to have it. Always wanted to buy a Fender Champion 600, but never did. I prefer the looks of Fender's model over Gretsch's.
#3
Quote by KG6_Steven
...I prefer the looks of Fender's model over Gretsch's.


I don't mind the looks of the Gretsch but agree the Fender looks better. I think the contrast between the cream and the dark brown sides makes it look smaller. My Nº1 600 looks even smaller as the speaker cloth is now almost exactly the same cream colour as the tolex.

600's still come up quite regularly on ebay, even in as new condition, so there is no excuse for not having one ;-)
#4
Nice work

you should be able to get a 4 ohm jensen c8r without too much bother. I haven't tried it, though, but i'm guessing a ceramic jensen would be along the lines of what you want tonally.
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Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#5
Quote by Dave_Mc
Nice work

you should be able to get a 4 ohm jensen c8r without too much bother. I haven't tried it, though, but i'm guessing a ceramic jensen would be along the lines of what you want tonally.


Thanks for your comments. It transpires Thomans stock Jensen speakers. They also suggest they stock a 4 ohm 8" Celestion, not sure on that as Celestion don't list one.
#6
yeah. hotrox seems to stock it too- slightly dearer but then unless you're buying other stuff from thomann they charge 10 euros postage...
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Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#7
Indeed so, but I have a voucher from Thomann which would cover postage.

Was looking at the amp this afternoon and I'm not convinced the Jensen would fit as the Bugera speaker only just misses the valve. The alnico speaker would be right out.

Also, looking at the frequency graphs of the Celestion and Jensen I'm thinking the Celestion would be the better option.

Thoman have emailed me to confirm they stock the Celestion in 4 Ohm so it seems rude not to have one.

However, The Bugera speaker seems better now that it has broken in a bit - it was brand new when fitted. So I may just stick with it for a bit.
#8
yeah if the bugera one is starting to sound ok then stick with that, at least until you decide what you want.

and yeah alnicos are normally bigger, if it's already a tight fit you might be in trouble. though some of the cheaper alnicos use smaller magnets. so might be ok, or might not.

and yeah celestion versus jensen just depends on the tone you want. personally i prefer using us-voiced speakers with US-style amps and british-voiced speakers with UK-style amps but that's just me, and it's hardly a rule
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#9
I have the 70's Fender Champ, a later model with bass and treble controls. Love it. Mine didn't have tubes or speaker when I got it, but for $8 I thought it was worth a chance. At first used a cheap Radio Shack speaker, which did pretty well, then later on found a dead Gorilla practice amp with no chassis, just a 8 "speaker. For a buck I grabbed it, that speaker makes the Champ sound great. I've been using it about 15 years now, still working perfect, and I had to patch a hole in it before putting it in the amp. Toilet paper and fingernail polish does a gret job of patching small tears or holes in speakers and holds up really well.

Anyway, if you happen to find a cheap Gorilla practice amp the speaker in it is definitely worth considering. The one I'm using has been excellent. Mine is this amp

http://www.ebay.com/itm/Vintage-Fender-Champ-1975-Silverface-Tube-Guitar-Amp-5-Watt-/331474521249

Looks almost as good as the one here, silver face plate is a little gnarly. Listing says 5 watt, it's actually a 6 watt amp, mine's a 74 model. Can't get a better practice amp...the one you have, single volume knob, I think that's the same amp Eric Clapton used to record the Layla album, and Joe Walsh used to record Funk #49. Not sure though, I've never found anything that specified which Champ they used, just that they used Champs.

Look at Sweetwater, I've had excellent results getting guitar strings from them, good prices too.

Here's their speaker list

http://www.sweetwater.com/c1069--Guitar_Amp_Replacement_Speakers
Hmmm...I wonder what this button does...
#10
I've ordered the Jensen C8R from Thomanns as I have a E10 voucher which was going to expire. I agree that the US speaker is appropriate to the US amp and it was the drop in treble which frustrated me over the Bugera speaker. I have to try the Jensen and if I end up making another baffel to off set the speaker further I am sure I could sell the original on ebay. In many respects a straight 6" to 8" swap kit, with speaker, may be a desirable lot.

I believe the "Layla Amp" was a 5F1 Tweed Champ - I have a real hankering for a genuine 1962 version. These are readily available on eBay but I don't have a spare $1000 to $2000 kicking around. The Tweed Champ had an 8" speaker so, considering my tone stack is switchable between 5E1 and 5F1 voicings, the Jensen should get me pretty close.
#11


Herewith with the Bugera driver. You can see how close it is to the valve. Probably not ideal to have the valve in such close proximity to the magnetic field of the speaker but, so far it seems fine.
#12
Nice, let us know what you think when you get the jensen.

And yeah that looks tight. I'm not sure if it's a problem or not. The vibration from being so close to the speaker might be a bigger problem than the magnetism, but I could well be wrong about that.
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Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#13
I'm thinking any vibration will only be structure transmitted through the box, so pretty much as previously. The valve isn't touching the speaker.

What is also rather nice is the existing valve guard still fits behind the speaker, again without touching.

It would be nice if the Jensen is the same size as it all fits snugly but nicely now.
#14
I have no idea
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Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#15


Herewith the modified internals.

The switch on the right was to switch out R7, switching the negative feedback loop in and out. It didn't appear to achieve anything of any note so R7 has now been removed completely.

I now use this switch to switch in C3. C3 is the same rating as original but I am tempted to reduce it to 10uF.
Last edited by John Sims at Feb 18, 2015,
#16
^ they always say the negative feedback makes the amp stay cleaner longer, but then the onset of distortion is more sudden. But , i've never tried it in the same amp where it was switchable.

nice work too
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Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#17
Jensen C8R arrived this morning.

I will most likely fabricate a new mounting baffle for it either way and nudge it over further.

I am pondering including a "Beam blocker" while cutting out the baffle. In effect a restriction in the centre to partially divert the high frequency sounds to produce a more rounded sound.

Apparently SRV would tape the inside of the centre of his speaker grills to the same effect. But this information did come to me from a company advertising after market beam blockers so might be marketing BS.

Considering, even though larger than a 6", an 8" speaker is still pretty tiny in guitar terms the beam blocker seems like a viable principal and doesn't involve any more than a more complicated cut out.
#18
I've never tried beam blockers, but if you're having problems with too much treble they might be worth a try. LOL at "Apparently SRV would tape the inside of the centre of his speaker grills to the same effect. But this information did come to me from a company advertising after market beam blockers so might be marketing BS."
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
#19
I didn't bother in the end and just cut out a round hole. Cloth all fitted and ready to mount tomorrow. 😊
#20
Jensen speaker fitted this morning - still to be soldered though.

Bit or a pain to fit as the Jensen basket is bigger than that of the previously fitted 8" Bugera speaker. To get around it I had to grind a small scallop out of the back of the amp chassis to clear.

Otherwise it misses everything and even allows the refitting of the back with the valve guard in place....which is nice. Apparently if you fit a 6" Jensen you have to remove the valve guard.
Last edited by John Sims at Feb 24, 2015,
#21
Soldered and tested and pretty damn superb.

With all the internal mods and the 8" Jensen this little amp is pretty formidable.

It can be uncomfortably loud in a living room and sounds much bigger than it is.

I think the Jensen was the right choice as it has restored the Fenderness that the Bugera had perhaps removed. It also gives much more relevance to the 5E1/5F1 switching.

It really is the original 600 on steroids; having all the desirable aspects of the original without the background noise and with much more weight in the sound.
#22
Nice, glad you like it

I suppose the one advantage of the smaller original speaker is keeping things quieter, though. sort of lets you crank it up at lower(ish) volumes. I have a fame tube 5 (glorified champion 600 with a jensen mod 6) for that reason.

EDIT: oh and i put a c10q in my vht special 6 a while back when thomann had it (speaker) crazy cheap for like £20 or something daft. it's pretty nice, that's why i thought an 8 inch jensen from the vintage/ceramic series might do what you want.
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?
Last edited by Dave_Mc at Feb 24, 2015,
#23
Thanks for your comments Dave, it did push me over the brink to get the Jensen and I'm very pleased it did.

I'm not sure there can be many advantages to the smaller speaker (aside being small). The larger size certainly gives more depth of sound and is perhaps no more difficult to play quietly. We all have a volume sweet spot below which the sound doesn't seem to come alive. With the silly cigarette packet amp I would run it flat out, not for the loudness just to get the sound to reach me so small certainly wasn't beautiful in that instance.

The 8" seems to allow the sound to flow out of the amp where the 6" seems to be forcing it out ...if that makes sense.
#24
Yeah I know what you mean. And thanks

That being said the little 6" jensen (~90dB IIRC) is noticeably quieter than my other speakers. For getting up to power tube distortion levels at (sort of) home-friendly levels it makes a difference. But I'd agree it probably doesn't sound as good as the bigger speakers, either.
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?