treble boost

[franz]

Long time no posts unfortunately and this one is like going to the doctor and asking about more than one ailment-not on.
However, having trawled through all the posts just now, I can't see anything on the supposed treble boost used by Hank on the early stuff, i.e when he was using the AC15s or AC30/4 without the addition of top boost.
I have a "Marshall" AC30 top boost with Roger Allcock's AC15 mod. To get the early tone, I use the treble boost pedal setting on my Tonelab. This produces through a Q2 EFTP and with Golden Sixties strings, the cutting, slightly "honking" sound,particularly on the middle p/u, of the early singles and first 2 LPs although it's not too accurate on some of the "bridge" numbers. Without it the sound lacks that cutting edge. (You have to be a bit careful to moderate the treble strings to eliminate any harshness.) No loss of tone either. The AC30 top boost channel produces a completely different sound.
Cutting to the chase, does anyone know what treble boost hank used with the AC15s? I have a feeling that a dedicated unit might produce better results still, although I have unpleasant memories of my cheap plug-in booster on an AC10 in the 1960s which ruined the harmonics.The amp was very bassey without it.
Next for the doctor is my inability to successfully e-mail the maker of the strings which are made in Germany and no longer sold in this country. Since they are the best I have ever used for the job,does anyone know how to contact them?
And lastly(sorry) re the posting on strat return springs which I have only just seen, the bridge can only be set to the correct pitch with the claw adjusted as far into the body as it will go and 4 springs. This is because of 12 gauge strings with a wound 3rd. The strat is a 62 so its old like me. I don't want to tighten up the retaining screws too much as this affects the free movemnt of the tremolo. Any idea anybody, please?

Franz

[JimN]

Never having owned an AC15 (I was an AC30TB owner from the age of 15), my understanding is that they always included an integral treble boost circuit (courtesy of the EF86 pre-amp valve) which was lost when the succeeding AC30 was switched from EF86 to an all ECC83 (plus one ECC82) valve line-up. The (slightly) later Top Boost circuit was an attempt to make up for the lost treble which had gone with the EF86.

JN

[Tab]

Without hearing your gear or playing with the controls, it's difficult to offer advice. However, it does sound as though the use of an ARIAB box or a Gemini pedal would help. These even out the bass/treble mix to good effect.

I have been using a Fender Super Champ XD for home use and mic'd it up through the PA for large venues and it produces quality vintage sounds - that 'bark' on middle pu and it works just as well on the bridge pu numbers. I acquired this amp second hand at a very good price and has been one of my best ever buys.

Re your strings - can't help with the German manufacturer, but I use DRs. I have two 57 re-issues which I use for early Shads stuff - one set up with 12-52s with a wound 24 and the other set up with 13-56s with a wound 26. Both guitars have 5 trem springs and I have no problem with the floating bridge. Tuning is never a problem but the guitars have to be set up properly.

Good luck.

Kind regards,

Terry

[rogera]

I have never heard any reports of Hank using a treble boost unit in the early years. One of the earliest amps that he used was a Selmer Stadium (also using an EF86 preamp) followed by the Vox AC15 which had a two way rotary selector switch marked 'Brilliance" on-off.

The use of the word 'Brilliance' in my opinion was rather misleading in so far as the result of switching to the Brilliance position only removed a significant portion of the bass frequencies. In no way did it increase the treble response.

One factor that also needs to be taken into account is the fact that the first stage of the Meazzi echo units that he used also removed a certain portion of the bass frequencies.
The factors mentioned above, coupled with not knowing what (if any) EQ changes were made during the recording process, give ample means to achieve the sound that we all know in those early recordings.

During the period that you mean I don't think that there were any 'treble boost' units available.

[franz]

Thanks, guys for your prompt and detailed replies. Roger and Jim seem to be agreed that the amp and Meazzi did the work themselves.
I shall look at the Gemini, particularly with reference to the evening out of the bass and treble response and give the DR strings as suggested, a try.
One thing that struck me yesterday, playing in a hall with almost no damping effects, is that it was quite different to playing at home in a small room. I had to use the AC30 cut control quite a lot to moderate the treble response although I still think that without the treble boost, that "bark" would have been lost, particularly on 1861 which I played. I ought to say also that without Roger's mod, I would not be able to get anywhere near to "that sound"
The strat tremolo unit performs perfectly well with the 4 springs but with 3 there is much more fluidity about it but of course it leaves the bridge at too high an angle for properly flattening notes/chords

Regards,

Franz

[peter roest]

Let me tell you what is technical Vox AC15 and AC30 treble boost or brilliant channel.
In the early sixties and still now the Vox has a small capacitor of 470-500pF (in Dutch koppelcondensator) after the first amplification step . Normally in amps is a value of 0.01- 0,1uF, 20 to 200 times higher. The small capacitor cut off the lower tones, you"ll miss them. At the end of the amp, in the poweramp between the push pull faseshifter
and the EL 84 valves, there is the cutcontrol. The cutcontrol consists of an potmeter 250 kohm and a capacitor of 0,47 uF like a shortcircuit between the two 180 degrees shifted signal conductors to the EL84's. This cut control will throw away the overdosis of high notes in the signal. So you get a "normal" sound out from your speaker(s). Poorely the highcut after the normal/tremolo channels gives then a a very dull dark sound.

Just like Roger says in the beginning (Jennings AC15 1960 and early Vox AC15) there was a normal/bright switch (still also nowadays in other brand amps).
It's still now a fairy tale in difference between an EC(C) 83 and an EF86 in the first step preamp. There is a difference between a triode and pentode. A triode gives odd and most even harmonics at heavy load. A pentode gives most odd harmonics at heavy load. In the first step, signal from the guitar the negative DC voltage of the grid in the valve is about 1,5 Volt. The output of the guitar is about 0,1 Volt (top 0,14 Volt), this is 10% load. This low load gives less than 0,1% distorsion(is nothing)
The EF86 gives max 120 times amplification. A half ECC83 gives simply 50 times amplification a complete ECC 83 can give 50x50=2500 times amplification.
The more bright tones in old Shadow stuff should be caused by the speakers (grey alnico's). A bandmember in my Shadowband has a 1964 Vox with those speakers. Those old speakers where not capable to give the low tone soutput of the modern guitarspeakers.
For getting extra high sharp guitar sound you can try a Behringer spectrum enhancer (like Spotnicks).

Something else,

Like more people I was not satisfied (like Amanda)of the sound of my Vox AC15CC1. The problem was the weak output of the bass tones. Like above there was in the schematics a 470pF after the first step. in the poweramp is a tonecut with the 0,47 uF capacitor and an straight 220 kohm resistor. This is insufficient. What i have done is replace the 470pF (C5) in a 10nF(=0,01uF) like older days. Now I have a very good amp with full and warm basses.
I found some helpfull information about demontage of the amp at http://www.guitarpug.com/2008/06/Vox-AC15CC-mod-guide/.
The owner (David Buntsma, a north Dutch name) of this site has removed my comment onder consideration (not readable for visitors). He puts people on the wrong leg (a dutch wisdom) poorely.

Peter (buizenkenner)