Caevan O’Shite

Yhup!

__ http://herbiesaudiolab.net/ultra9.jpg The several Teflon HAL-O 9 Tube Dampers that I have were given to me by a very good friend years ago, but here is a link to the 'site for them: Herbie's Audio Teflon HAL-O Dampers Shop around for the best price; you may find used dampers for sale, other models, or dealers with sales-incentives that may reduce your cost below the MAP (Minimum Advertised Price) allowed by the manufacturer. I can't say anything either way to some of the audio-enhancing claims that are made about these, but I can say that they worked like a charm for negating the microphonic problems I had, and thus have added several years to the usable life of the tubes I put them on- and still are. They've also stood up to the considerable heat of the tubes.

Gheeze, I'm havin' a hard time pinpointing that! It was while Myles still worked there at GT, probably five or six years ago or so; he kindly hand-picked a set for me and they're still going strong, as is the matched, "#5"-rated EL84S quartet. The SAG MHG pres developed a little microphonic tendency, but that was easily cured with a couple of Hal-O tube-dampers- nary a whistle, ring or squeal since! All of the GT tubes that I put in that amp- during Myles' tenure there- have lasted much longer than I would have expected, including the output-tubes. There were good stretches of time where the amp saw little use, but when used I push it very hard- and I've been using it a LOT and using it HARD this past year and a half!

Wow- that's terrible. FWIW, the GT SAG MHG Kit that I bought was put together and signed-off by Myles himself, when he still worked there with his own equipment. Hey, renips, congratulations, I think you're going to be very pleased- I purchased that same SAG MHG Kit myself, and it made a whole new amp out of my little Carvin Vintage 33! ESPECIALLY the MPI- what an improvement!

Hey, renips, congratulations, I think you're going to be very pleased- I purchased that same SAG MHG Kit myself, and it made a whole new amp out of my little Carvin Vintage 33! ESPECIALLY the MPI- what an improvement!

I think that the Vintage 33 was the best of that line, and it got the least support, promotion, information... It seems to be the hardest to get solid info on!

Say, Myles- I had previously been under the impression that my Carvin Vintage 33 combo was cathode-biased, but have recently discovered that (A) upon opening it up, it is apparently "fixed-bias" with a bias-pot and cathodes going to ground with nothing in-between and (B) it does not seem to quite match up with the schematics that Carvin sent me years ago. It DOES have the model name "Vintage 33" screened on the back of the chassis... unlike some iterations of the 33, it has an effects-loop, compensated direct-out, and their active "Presence"-control on the back... ? ANYWAYS, I've been trying to figure out if I can just go ahead and use the recommended methods and specs given for biasing Carvin's "Vintage" series Bel Air/Nomad amps (the Vintage 33 is vaguely mentioned at one point)... any tips or recommendations?

Myles, how're ya doin'?

In a way, that's sort of still the recipe!

Thanks, Myles! I kinda thought more or less the same, myself; I figure that, there're versatile amps that are good for almost everything BUT mo' modernish "mid-scooped metal"; and then there're amps that are good at more extreme modern "mid-scooped metal", that are too hard, tight, stiff, for nearly "everything else". MAYBE "almost everything else" and '70s to early/mid '80s "Metal" can be reasonably done by a good channel-switcher like a Fuchs, Rivera, MESA/Boogie, etc., especially by a player with a good "touch" and grasp of "playing the amp"; but there seems to be a dividing-line between those that can reasonably do "Country/Blues/Classic-Rock/etc." and those that can convincingly do heavier, chunkier, more percussive mid-scooped "Modern Metal".

Myles- What might be some of your recommendations for an amp-shopper, willing to spend in the range of $3k or so, looking for a "do it all" channel-switching amp with three or four channels? (Three channels minimum.) He wants "to be able to play everything from the blues to hillbilly country to classic rock to mid-scooped metal." Variable power is a plus for him, too, whether different watt settings, "Power Scaling", "Master Voltage", etc. He will be using the amp at home, in the garage, AND, in time, with bands... Any promising candidates in the up to $3k +, multi-channel, "do it all", chunky/scooped metal-capable tube-amp category?!

Thanks, Myles!

Hey, Myles- am I correct in saying the following? "on MOST guitar amps, the treble, middle and bass controls only attenuate frequencies; they do NOT "boost" anything, unless they are specifically active-EQ circuit designs made for both boost AND cut." I was replying in response to the following: __________________________________________________________________ "Tone Controls Magnetic guitar pickups are inductive, and require compensation, although this opportunity is also used for tone enhancement, not just correction. Without compensation, they have a strong low middle emphasis and little high frequency response - overall a very muddy and muffled sound. This is why typical hi-fi Baxandall treble & bass controls are unsuitable. To hear the natural sound of a pickup, use a typical guitar amp with the middle set to full, and bass and treble on zero. This is actually sets a flat response in the amp (see below), and I expect you will hear a muffled and muddy sound. And that's the whole point of these tone controls providing compensation for the natural sound of a pickup - the middle control simply boosts the pickup's normal middley sound. The treble and bass controls do the opposite - they boost higher and lower frequency levels, leaving a notch in-between for middle cut (see the Fender/Marshall comparison below). So with typical settings of a bit of bass, middle and treble, the overall tone equalisation complements the natural pickup sound for a balanced response of lows, mids and highs. Full middle boost with no bass or treble actually gives a near-flat frequency response, allowing you to hear the natural sound of your pickups. Here are circuit diagrams of typical Fender and Marshall tone controls. They both meet the criteria of compensating for pickups' low-middle emphasis, as well as providing a useful range of tone adjustment. The Fender and Marshall circuits are each tailored to suit their own styles, which are quite different. Although a generalisation, Fender's market and power output stage are geared towards provided clean and chunky tones at clean and early-overdrive levels. Marshall amps are best at low-middle and crunchy rock tones, played at medium to high overdrive levels." __________________________________________________________________

janealex- do you mean that the bass is inconsistently changing pickup-selection or making weird noises, or do you mean that the bass amplifier is making strange, inconsistent sounds?

Cool, thought so, but was leery, especially considering how hard I push the amp, and tube-amps in general. Thanks!

Hey, Myles- Just how safe is it for me to run my Fuchs Lucky 7 with an 8 ohm speaker-out into my old GT Electronics Speaker Emulator (the original model) set to 16 ohms? Is this alright, or should I set the Sp Emu to 8 ohms? Particularly considering that I tend to push the amp hard, very often running the Lucky 7's volume full-up, "playing the amp" with my dynamics and the guitar's volume-knob... and I also sometimes hit the amp's input pretty hard with the boosted output from various pedals, including octave-up AND octave-down fuzz from an Octron (and even two octaves down from a Blue Box). I figure, this must be a torture-test at the very least, and wonder about this impedance mismatch... I like the way the Lucky 7 sounds and feels when the Speaker Emulator is set to 16 ohms, as actually recommended in the GTE Sp Emu owners-manual. It's subtly, but noticeably, different from being set to 8 ohs. Thanks in advance for your time and effort!

True; now, anything that's NOT easy to fix, WILL REPEATEDLY break down on you!

Hmmmnnn... Say, Myles, would it be unwise to put a G12H 30 or similar 30-watt speaker like the Weber AlNiCo 1230 in my 1x12 Carvin 'Vintage 33', which is apparently rated at a nominal 33 watts? I do tend to push the amp hard, using my guitar's volume-control to vary cleaner and dirtier tones, and sometimes punish it with pedals like a Foxrox Octron...

Believe me, I understand that all too well! In a similar boat lately, myself. If it's of any help, I found a used H&K Red Box being auctioned here on e-Bay... And while not ideal (but not bad- I used to have one, myself), somewhat overkill for your specific task, and only marginally cheaper, something like one of these might be a more affordable option for you...

Kimsky- I edited my previous post; I realized that with the Surprise Sound Lab SE-5 that I'd linked you to, you can run your AC4 WITHOUT connecting a speaker or an additional load. With the Red Box and JDX Reactor, though, I believe that you still have to have a real speaker or suitable safe load connected, as per the directions of the given DI units manufacturers.

(Chiming in again) Correct me if I'm wrong, Myles, but I don't think that would be a good idea, Kimsky. And be careful not to void your AC4's warranty while it's still valid! In short, you need a real speaker or suitable safe load connected to the speaker-output of the amp. To safely do what you want, you need one of these, or one of these, or one of these. Note that with the SE-5, you can run your AC4 WITHOUT a speaker or an additional laod; with the Red Box and JDX Reactor, though, you still have to have a real speaker or suitable safe load connected, as per the directions of the given DI units manufacturers.

Thanks, Myles.

Glad to hear it, especially from you, Myles! Thanks. Hey, Zephyr- if I had the dough right now, I'd pounce on this, whether I was me OR you... ! ___________ http://img.photobucket.com/albums/v696/bunyok23/IMG_2233.jpg

Carl Verheyen uses a THD Hot Plate to do this and it works pretty well. If I may chime in, the GT Electronics Speaker Emulator, the Marshall SE100, and the Palmer Speaker Simulator are/were all made for this type of application and excel at it. All use reactive-load designs. They may be a bit hard to find, though! And, they're not inexpensive. I can highly recommend the GT Sp Emu, I have an old one, the original version (and will not part with it! ), with a 3-band "pole filter" resonance EQ. It can take a while to dial-in just-right; the input and output levels are key here. The GT Sp Emu II has a more conventional, amp-like EQ, three levels of attenuation for live speakers, and an effects loop. While either would work excellently with most any tube-amp, I feel that the earlier model is particularly suited to "British" flavors, with the second model being a bit better for Fendery sorts. Again, though, both work well with either. ____________________________________________________________ I once put a Marshall SE100 through its paces (and I regret not having bought it!), and it was particularly excellent. It uses the same reactive-load design as the GT models under license, and adds some interesting features like a three-selection mic-position simulation. It worked beautifully with the Fender Twin I had at the time; and, of course, it works very well with Marshalls and other "British" types. These are highly sought after in the used market... ____________________________________________________________ Remember James_Italy, who used to post here a lot a few years back? He got, and loved, a Palmer Speaker Simulator, and had posted some excellent sounding demo clips using it to record direct. I'm convinced that the Palmers are at least the equal of the GT and Marshal speaker emulators, if not even better. You may even be able to score a new one, though a used one might prove to be more cost-effective...

Aaaah, I should have realized that to begin with, d'oh! I COMPLETELY forgot about the cathode-biasing being a factor here... THANKS, Myles!! You can do this is grid biased amps but not in your Carvin cathode biased amp. Cathode biased amps expect all the output tubes to be there as the bias is self adjusting and one of the factors is the tube load. Bottom line - never do this on a cathode biased amp. Or, other than a handful of EL84 amps, never do this on an EL84 amp.