Vox / Orange / Apollo - Treble and Bass Booster  [schematic]

Discussion regarding early stompbox technology: 1960-1975 Please keep discussion focused and contribute what info you have...
User avatar
sinner
Old Solderhand
Information
Posts: 4709
Joined: 06 Nov 2008, 17:16
Location: ...no more
Has thanked: 1031 times
Been thanked: 908 times

Post by sinner »

shit, values were missing

again...

User avatar
SonicDaeath
Information
Posts: 21
Joined: 30 Nov 2010, 22:50
Has thanked: 7 times
Been thanked: 14 times

Post by SonicDaeath »

Here is my take on the Vox treble and bass booster. I used Gottfried Divos' schematic. I wanted to make a layout with no cuts...

As yet unverified, once I set my workshop up again in Alaska I'll build it up.

Image
Attachments
Vox- Treble and Bass booster.jpg
Vox- Treble and Bass booster.jpg (40.88 KiB) Viewed 3047 times

User avatar
SonicDaeath
Information
Posts: 21
Joined: 30 Nov 2010, 22:50
Has thanked: 7 times
Been thanked: 14 times

Post by SonicDaeath »

I forgot to add input via T/B: lug 2.

User avatar
MildSilverbirdApps
Information
Posts: 5
Joined: 18 May 2012, 00:49

Post by MildSilverbirdApps »

Thanks Pedalman85 for sharing your schematic - I built it and it works like a charm.

I too tried building from one of the other Apollo boost schems on the web and it was obvious something was seriously wrong. I figured it might have been the base and collector loads at fault but wasn't sure.

Great work. Many thanks!!!

User avatar
Harold
Breadboard Brother
Information
Posts: 77
Joined: 21 Oct 2008, 21:06
Location: The Netherlands
Has thanked: 7 times
Been thanked: 21 times
Contact:

Post by Harold »

Pedalman85 wrote:soooo sorry folks! forgot pw and forgot that i made this enjoy. Note: S1 and S2 is a DPDT slide switch.
@Pedalman85: thanks for the schematic! :thumbsup Did you build a clone yourself?

I don't have any 2SB175's at hand, so I will try a AC128 first ...
DIY-Layout.com: Online stripboard layouts

User avatar
Pedalman85
Information
Posts: 15
Joined: 27 Apr 2009, 19:19
Has thanked: 2 times
Been thanked: 11 times

Post by Pedalman85 »

Harold wrote:
Pedalman85 wrote:soooo sorry folks! forgot pw and forgot that i made this enjoy. Note: S1 and S2 is a DPDT slide switch.
@Pedalman85: thanks for the schematic! :thumbsup Did you build a clone yourself?

I don't have any 2SB175's at hand, so I will try a AC128 first ...

No I haven't been able to find 2SB175's and I've been preoccupied with a PT2399 based delay pedal build/design as well as a load of other projects. I did find some 2SB176's not sure if they would sound the same but I'm going to give them a try once I get a order together.

Best of luck with cloning it! :thumbsup I'm sure some of the part will need to be substituted (like the caps) but most of the closest values should be with in tolorences.
I'd say if ya do build one, slap a 1M pulldown resistor on the input (soldered between the signal and ground of the input Jack) to tame the pop when it's turned on. Some power supply filtering/protection would be a bad idea either.

User avatar
Harold
Breadboard Brother
Information
Posts: 77
Joined: 21 Oct 2008, 21:06
Location: The Netherlands
Has thanked: 7 times
Been thanked: 21 times
Contact:

Post by Harold »

Pedalman85 wrote:I'd say if ya do build one, slap a 1M pulldown resistor on the input (soldered between the signal and ground of the input Jack) to tame the pop when it's turned on. Some power supply filtering/protection would be a bad idea either.
Well, I already created this layout for it:

Image
Apollo treble bass booster


... I guess some filtering could harm either ... :thumbsup
DIY-Layout.com: Online stripboard layouts

User avatar
Harold
Breadboard Brother
Information
Posts: 77
Joined: 21 Oct 2008, 21:06
Location: The Netherlands
Has thanked: 7 times
Been thanked: 21 times
Contact:

Post by Harold »

Hmmm... "You cannot edit your posts in this forum"

I meant to say: some filtering couldn't do any harm. And the link to the layout: http://diy-layout.com/76
DIY-Layout.com: Online stripboard layouts

User avatar
Pedalman85
Information
Posts: 15
Joined: 27 Apr 2009, 19:19
Has thanked: 2 times
Been thanked: 11 times

Post by Pedalman85 »

Very nice layout, it even looks like it might be about the same size board as in the original.
I personally have never used a strip board for projects (mostly perf or multipurpose) but I might have try my clone like your layout.

A couple of mods I thought of were replacing the output pulldown resistor with a pot for volume control or maybe replace the resistor in the tone stack with a pot (and maybe a fixed resistor in series) for a sort of scoop/timbre control. And of course there are endless combos for the caps in the tone stack. Idk just some ideas :)

User avatar
Harold
Breadboard Brother
Information
Posts: 77
Joined: 21 Oct 2008, 21:06
Location: The Netherlands
Has thanked: 7 times
Been thanked: 21 times
Contact:

Post by Harold »

Pedalman85 wrote:A couple of mods I thought of were replacing the output pulldown resistor with a pot for volume control
You mean that the current pot is for treble or bass and not for volume?
DIY-Layout.com: Online stripboard layouts

User avatar
LucifersTrip
Resistor Ronker
Information
Posts: 413
Joined: 06 Aug 2010, 10:39
my favorite amplifier: Companion Psychedelic Machine
Completed builds: Mosrite Fuzzrite (Si), Mosrite Fuzzrite (Ge)[2], Get Lo-Fi Fuzz, Fuzz Face (Ge) [2], Fuzz Face (Si) [3], Mos-Face, Vox Tone Bender, Kay Tremolo, Os Mutantes Fuzz [2], Psychedelic Fuzz, Smokey Amp, Sunn Buzz, Jen Fuzz, Fancy Fuzzbox, Muff Fuzz (op amp) [2], Buzz Box, Fuzz King, Rangemaster [5], Maestro FZ - 2/3, Ruby Amp, Orpheum Fuzz (Ge) [4], Great Destroyer, Schizo, Carlsbro Suzz, Shin-Ei Companion Fuzz (si), DOD 250 Gray [2], Super Dirt Fuzz, Fuzz Factory, Jordan Boss Tone, Sam Ash Fuzzz Boxx, Heathkit TA-28 Fuzz, Olson New Sound Fuzz, LRE Fuzz Sound, Green Ringer, Vox Super Beatle (Ge), Colorsound One Knob (Ge), Demon Buzzz [2], Demon Wasp v1, Demon Wasp v2, Super Hard-On, Bazz Fuss, Burns Buzzaround [2], Selmer Buzztone, Shin-Ei Companion Fuzz (Ge), Fuzz Face/FY-2 (Ge), Zonk Machine, Univox Squarewave, Demon Fuzzz, Mosrite Fuzzrite BG-500/1000 (Ge), Univox Superfuzz, Marshall Supa Fuzz, Demon Monster, AA Overdrive/ Retro Fuzz, Tone Bender MKII, Psychtar, Jordan Vica Vibe, etc...
Has thanked: 19 times
Been thanked: 71 times
Contact:

Post by LucifersTrip »


User avatar
Harold
Breadboard Brother
Information
Posts: 77
Joined: 21 Oct 2008, 21:06
Location: The Netherlands
Has thanked: 7 times
Been thanked: 21 times
Contact:

Post by Harold »

Ah, found an error in my layout which sent the bass side straight to GND ;)

Fixed the layout: I now have a bass or treble booster! :applause: Well "booster" isn't the correct term as it has a volume drop. :(
DIY-Layout.com: Online stripboard layouts

User avatar
R.G.
Resistor Ronker
Information
Posts: 337
Joined: 22 Sep 2007, 02:24
Been thanked: 39 times

Post by R.G. »

Replace the two 220nF caps on the front end with 47nF to 100nF.

User avatar
Pedalman85
Information
Posts: 15
Joined: 27 Apr 2009, 19:19
Has thanked: 2 times
Been thanked: 11 times

Post by Pedalman85 »

alright folks i've finally got some 2sb175's to try to clone the Apollo booster. btw small bear is currently carrying them as well as 2sb176's. so i had to sub in 2200pf, 33uf, 4.7uf caps and a 33k resistor. the original 2sb175 had an A labeling for it's Hfe range and the ones from small bear are all B's. they come in at about 270-400 Hfe, much higher then the datasheet says they should be but oh well.

So as Harold put it's not quite boosting as it's name would imply. Here's the problem!!! I A/B the breadboarded with the original and the original has a noticeable boost and the breadboarded clone has a drop!
As far as i can tell all the voltages are close to a match with the original. The original draws about 480uA while the breadboarded depending on the transistor is any where from 307uA-900uA.
i've even tried sb176's in it and was pleasently surprised at how much less hiss was present.

I have messed with different values in the voltage divider and both the collector and emitter pins but i haven't noticed much change.

so my questions to you fine people are: would i only need to change the 10k resistor on the collector to bias? and is there any possable way to measure or rough guess what the original transistors Hfe is without removing it from the circuit?

Post Reply