Basic amp questions

ACR4V3N

New member
Ok, I have a bogner alchemist 112, and like it quite a bit, but I'm looking to enhance the sound to better get a chrunchy raw sound.

First off, I am thinking about some extension speakers. The back of the amp says "connect either a 8 ohm pair, or a 4 ohm single" and the amp can go between 20 watts to 40 watts. I was wondering if it would better get the desired sound if I wired up 2 8 ohm pair in series to the amp. How much different would it be using a amp like that as a head? Like what actually is the difference between using a amp head and using the 112 as a head.

Secondly, its still got the stock tubes in it which are about to be due for replacement. What could I put in there to get a better, thicker distortion. How much do tubes effect the eq of the amp, and can it reduce the mids? (The amps mids are hard to dial in sometimes, and I wish they would be less present)

Thirdly (and lastly), when people talk about modding an amp, I take it they mean some type of surgery, such as replacing capacitors, resistors and what not. How can I get started with that? From my understanding, bogner/line 6 havent ever released any of the schematics, so am I out of luck?
 
Re: Basic amp questions

two 8 ohm speakers in series will be 16 ohms and not what you want.

two 16 ohm speakers in parallel will be 8 ohms
two 4 ohm speakers in series will be 8 ohms

tubes will effect the sound but in that amp i it has a digital preamp so im not sure how much change youll hear from one tube set to another. a good set of tubes wont hurt either way
 
Re: Basic amp questions

two 8 ohm speakers in series will be 16 ohms and not what you want.

two 16 ohm speakers in parallel will be 8 ohms
two 4 ohm speakers in series will be 8 ohms

tubes will effect the sound but in that amp i it has a digital preamp so im not sure how much change youll hear from one tube set to another. a good set of tubes wont hurt either way

Maybe I'm mistaken but the Alchemist is tube preamp, the Spider Valves are digital.
 
Re: Basic amp questions

tubes will effect the sound but in that amp i it has a digital preamp so im not sure how much change youll hear from one tube set to another.

The Bogner Alchemist is an all analog signal with separate digital effects run in parallel per Reinhold. The user manual states "Two channel All-Tube design, 100% pure valve signal path".
 
Re: Basic amp questions

two 16 ohm speakers in parallel will be 8 ohms
two 4 ohm speakers in series will be 8 ohms

tubes will effect the sound but in that amp i it has a digital preamp so im not sure how much change youll hear from one tube set to another. a good set of tubes wont hurt either way

So two 4 ohm speakers in series 40 watt'ers would do the trick, yeah?

Also, it is an all tube amp, and what kind of tubes would be suggested?

this is what the manual says:
Your Alchemist comes with a matched pair of 6L6 power amp tubes depending on availability. Five 12AX7/ECC83 tubes are used in the pre amp. See below for individual functions.
Note: If you want to experiment with different tubes, you can reduce the potential for amp noise by 1) choosing lower gain tubes, and 2) placing any higher gain tubes earlier in the signal chain (the signall flows in order from V1, to V2, etc.).

I cant confidently translate that enough to make a decision on tubes.
 
Re: Basic amp questions

Does the manual say anything more about the tube layout? What V1 is etc.
In most amps V1 is the first pre-amp tube, changing this one out will make the most difference. Try a 'high-gain' type of tube in there for more crunch. If thats not enough, try one in V2 too.
 
Re: Basic amp questions

• V1 - First stage, Channel 1 and Channel 2 / Second stage, Channel 1
V2 - Crunch stage, Channel 1 / Second stage, Channel 2
• V3 - Third stage, Channel 2 / Fourth stage, Channel 2
• V4 - External FX Loop / Internal FX
• V5 - Power Amp Phase Inverter
• V6 & V7 - Power Amp Tubes

I'm having a hard time making sense of this whole tube thing, like, what is 6l6 and the other kind? Are tube sizes pretty universal?

Back to the speaker question: Is it just a matter of preference as to the speaker size or do they need to match the original (12")? And do they need to be 40 watts if they're in series? Also, what actually is the difference between the alchemist 112 amp and the alchemist head?

I know this is noobish but when it comes to this stuff I'd much rather be safe in the taking stake with in the wealth of this forum than sorry and a dead amp on my hands.
 
Re: Basic amp questions

Adding an extension speakers will not really get you more crunch...nor do I think changing tubes will drastically change the way the amp sounds (fine tune the sound maybe, but not fundamentally change it). If you want more (or simply different) crunch, how about a nice pedal of some kind?

In terms of modding the amp, it is likely a PCB amp, so modding it will not really be very easy...I think a pedal or two might get you some different sounds.
 
Re: Basic amp questions

This might be hijacking the thread, but why does the V1 make the most difference? Most or all of the amps distortion is generated after that tube, so wouldn't that make the first tube the least important one in tone generation? In clean channels it does make sense as it is the only tube doing the pre amplifier amplification, but with distortion channels this most definetly is not the case.
 
Re: Basic amp questions

the most tone shaping almost always happens in the first stage whatever that is. in this case v1a. everything else is just massaging the signal that comes out of that.

if the amp uses 6l6 tubes then you probably should stay with 6l6 unless you want to bring it to a tech. v4 doesnt matter all that much as long as its a decent tube of the right type
 
Re: Basic amp questions

• V1 - First stage, Channel 1 and Channel 2 / Second stage, Channel 1
V2 - Crunch stage, Channel 1 / Second stage, Channel 2
• V3 - Third stage, Channel 2 / Fourth stage, Channel 2
• V4 - External FX Loop / Internal FX
• V5 - Power Amp Phase Inverter
• V6 & V7 - Power Amp Tubes

I'm having a hard time making sense of this whole tube thing, like, what is 6l6 and the other kind? Are tube sizes pretty universal?

Back to the speaker question: Is it just a matter of preference as to the speaker size or do they need to match the original (12")? And do they need to be 40 watts if they're in series? Also, what actually is the difference between the alchemist 112 amp and the alchemist head?

I know this is noobish but when it comes to this stuff I'd much rather be safe in the taking stake with in the wealth of this forum than sorry and a dead amp on my hands.

So you want to turn you combo into a headshell and get a 2x12 speaker cabinet?

Don't you think it's just easier to sell this one and get a bigger amp? Bigger amps will sound bigger but also much louder!

If you have to mod it that much, ask yourself if this amp is the right one for you anyway. Why did you buy it in the first place?
A mint Bogner has good resale value, you could destroy that by doing mods to it, then find out it's not what you wanted.
Nobody wants to buy an amp that has undergone someone elses learning curve surgery.

Before you run out and change the world, ask yourself... What do you really want?!
 
Re: Basic amp questions

For what its worth, Avatar has thier special order Celestion G12T100 4 ohm speakers on sale for $59. But, before you go there...

Aged tubes can lose thier bass and treble response enough to "appear" to accentuate the mids. This can sound really cool in a low gain amp but not so much in a higher gain amp where it would start to just sound wimpy.

I would have the tubes (and possibly the amp) checked by a tech before you start throwing speakers at it. If you end up having to replace the power tubes (6L6's), the amp will have to be biased for the new tubes, so a visit to a tech would be warranted anyway (I assume you don't have means to do it yourself). Consider it as a periodic wellness check for your equipment.
 
Re: Basic amp questions

Ok, I have a bogner alchemist 112, and like it quite a bit, but I'm looking to enhance the sound to better get a chrunchy raw sound.

Secondly, its still got the stock tubes in it which are about to be due for replacement. What could I put in there to get a better, thicker distortion.

Thirdly (and lastly), when people talk about modding an amp, I take it they mean some type of surgery, such as replacing capacitors, resistors and what not. How can I get started with that? From my understanding, bogner/line 6 havent ever released any of the schematics, so am I out of luck?

1. trade an amp for something more metal - Engl like?
2. what pickups do you have?
3. yep, surgery it is.
Without thorough electronic knowledge ones only hope is to wait for someone to post the mods, and then choose if he likes it after hearing the outcome (on YTube for example)

I'm having a hard time making sense of this whole tube thing, like, what is 6l6 and the other kind? Are tube sizes pretty universal?

Back to the speaker question: Is it just a matter of preference as to the speaker size or do they need to match the original (12")? And do they need to be 40 watts if they're in series? Also, what actually is the difference between the alchemist 112 amp and the alchemist head?

I know this is noobish but when it comes to this stuff I'd much rather be safe in the taking stake with in the wealth of this forum than sorry and a dead amp on my hands.

1. Amps use preamp, poweramp and rectifer tubes. So you have three different types you'll get to know.

preamp - 12AX7, 12AU7... (small tubes, in amp may be in metal encapsulation for noise issues)
Tube reverb/vibrato or tube FX loop in more expensive amps for top notch feel and sound quality.

rectifiers - GZ34, 5U4 large, fat

power amp - 6L6, EL34 orange/red glowing tubes large (EL84 bit smaller, different pins)

http://music-electronics-forum.com/attachments/7375d1261936346-mesa-boogie-tete-dual-road-king-3.jpg
http://drewsgeezeramps.com/images/Marshall-1987/CabinetRear1.jpg
This is pretty basic explanation. If you want to know more, just ask.

2. If you have 40W amp, I'd recommend a speaker that can handle a bit higher power. You'll be OK with a 60W speaker.
It can be 2x 30W speakers or 4x 15W. It's just important to match the impedance (depends on cab wiring diagram) of your cabinet to your amps output.

3. It would be stupid to burn your amp by tweaking around things you're not familiar with, while there are people willing to help you with an advice here :)


Adding an extension speakers will not really get you more crunch...nor do I think changing tubes will drastically change the way the amp sounds (fine tune the sound maybe, but not fundamentally change it). If you want more (or simply different) crunch, how about a nice pedal of some kind?

In terms of modding the amp, it is likely a PCB amp, so modding it will not really be very easy...I think a pedal or two might get you some different sounds.

+1
Try couple of pedals, or some nice pickup booster on drive channel.
If it don't get you where you want, or you get to much mush, consider amp swapping.
You don't want to waste your time trying to make a PC out of Mac. Trust me, been there :)

This might be hijacking the thread, but why does the V1 make the most difference?

Glassman can help here.
Maybe V1 amplifies signal the most? (in relative units)
If you have 1V signal out of guitar (peak to peak) what would it be after V1 and what would it be at the last gain stage?


A mint Bogner has good resale value, you could destroy that by doing mods to it, then find out it's not what you wanted.
+1
 
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Re: Basic amp questions

Ok, I have a bogner alchemist 112, and like it quite a bit, but I'm looking to enhance the sound to better get a chrunchy raw sound.



 
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