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Jackson Ampworks Bass Amp Poll
- Thread starter JacksonAmpworks
- Start date
JacksonAmpworks said:
The reason, I think, that most bassist want to be able to "blend" a clean channel and a distorted channel is due to thier experiences with high quality distortion pedals that do this. A purely distorted bass sound loses much of the ability to cut through a live mix. For this reason, most players like to blend a clean signal back into thier sound.
Akami said:
Seriously this is a REALLY cool idea, but it will compromise the tone of each channel. Also there would be phase issues to address that would require that I alter the gain structure of one of the channels.
It works like this:
The 6SL7 channels has two gain stages.
The 12AX7 has two gain stages.
If I mix these two channels together, they will cause phase problems with each other. The only way to avoid this is to add a gain stage to either the 6SL7 or the 12AX7 channel.
Think of it this way: The number of gain stages in the channels that are going to be blended cannot both be even or odd. For instance, a 2 gain stage channel cannot be blended with another 2 gain stage channel. One of the gain stage numbers has to be odd and then it can then be mixed with a channel that has an even number of gain stages.
Is that clear as mud?
The reason that I say that is to demonstate that having a blend control will necessitate the modification of one of the channels, which would unfortunately alter the original tone of each channel.
- Apr 3, 2003
- 35,515
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- Editor-in-Chief, Bass Gear Magazine
JacksonAmpworks said:
Right on. Gotcha. Two isolated channels it is!
But if so, is it possible on Channel 2 to blend overdriven/distorted tone with clean? Might this require a second tube on Channel 2? If it's not going to work, that's cool, but it's just that once I heard how nice I could get an overdriven tone to sound once I blended in some "clean" low frequencies, I'm kinda hooked on that tone.
Tom.
If the signal from both channels was properly buffered and not merged until just before being sent to the power section wouldn't that keep the purity of signal intact?JacksonAmpworks said:
It seems like such a desirable capability, to choose blend levels, that there must be some way to make it workable and, albeit expensive, preserve the signal as desired.
haujobb said:
That I can't say. I'm going to use Toroidal transformers and those are half the size and weight of the usual EI transformers. That right there should make a huge difference in weight. I'm also going to try to keep the chassis as narrow as possible.
tombowlus said:
I see what you're saying, but at the moment I can't think of a way to do this without compromising the individual channels. I'll read into this and see what I can come up with.
Akami said:
The issue is really not about buffering the signal, but about phasing. That's what really hinders the feature. It could be done, but I would have to alter one of the channels and the concensus seems to be that tone is the first priority.
I'm still looking into this. I'll let you know what I find and if this is doable.
I forgot to mention something guys. 
Actually this one just dawned on me while I was working on the schematic for the amp. We have been talking about adding a gain stage for a while and it just hit me.... THIS AMP ALREADY HAS A GAIN BOOST ADDED!!!
The FX loop is buffered with a tube and then sent to the FX send, the FX Return has a Tube Gain Stage that is meant to amplify the return signal back to line level. While thinking about it, I realized that all you have to do is put a patch cable between the FX SEND and RETURN and now when the FX Loop is enabled, all you have to do is adjust the send and return levels to adjust the ammount of gain boost that you want. This gain boost would apply to both channels and would make a great level boost or OD boost!!
Now we have it all! Independant channels + a gain boost!
Actually this one just dawned on me while I was working on the schematic for the amp. We have been talking about adding a gain stage for a while and it just hit me.... THIS AMP ALREADY HAS A GAIN BOOST ADDED!!!The FX loop is buffered with a tube and then sent to the FX send, the FX Return has a Tube Gain Stage that is meant to amplify the return signal back to line level. While thinking about it, I realized that all you have to do is put a patch cable between the FX SEND and RETURN and now when the FX Loop is enabled, all you have to do is adjust the send and return levels to adjust the ammount of gain boost that you want. This gain boost would apply to both channels and would make a great level boost or OD boost!!
Now we have it all! Independant channels + a gain boost!
- Apr 3, 2003
- 35,515
- 19,942
- Disclosures
- Editor-in-Chief, Bass Gear Magazine
JacksonAmpworks said:I forgot to mention something guys.
The FX loop is buffered with a tube and then sent to the FX send, the FX Return has a Tube Gain Stage that is meant to amplify the return signal back to line level. While thinking about it, I realized that all you have to do is put a patch cable between the FX SEND and RETURN and now when the FX Loop is enabled, all you have to do is adjust the send and return levels to adjust the ammount of gain boost that you want. This gain boost would apply to both channels and would make a great level boost or OD boost!!
Now we have it all! Independant channels + a gain boost!
Interesting! I presume this would be just "clean" gain, meaning no additional overdrive introduced, right?
Tom.
tombowlus said:
No it would be however much OD you want depending on where the send and return levels are set. Sounds like it would be pretty cool. Basically you're just adding one more gain stage to the amp.
- Feb 27, 2005
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- Full disclosure, I'm a certified Fender technician working in a music store that carries Fender, Yamaha, and Ibanez products among others.
I just noticed how this poll is going, what with the OD channel winning at this point. Is there really that much demand for overdriven bass? Personally, hitting the first gain stage with a hot signal is enough for me about 95% of the time. I voted gain boost.
I really want to hear this amp when it's done.
I really want to hear this amp when it's done.
That sounds pretty cool. That way you could blend the channels with an A/B/Y box, but keep the tones of both channels uncompromised and pure otherwise.
jabberwock777 said:
yes, i'm of the four who voted for the non-OD amp, but hey, i'm actually starting to figure the benefits, especially in a trio setting.
jokerjkny said:
Which is why i wanted it
I'm usually playing in a Keys/Drum, or Guitar/Drum trio. That OD really helps me let loose and fill up space with acrobatics or singing notes when necessary.
Will the channels have multiple inputs like Marshalls and Fenders have had, where one channel could be "jumped" into the other? Could you "jump" the clean channel into the OD?
Does that make any sense, or does any one who may be able to articulate it better understand what I'm referring to?
Edit: I realize after posting that this wouldn't create a blended signal, but a hotter signal being fed into the other channel. Not really what y'all are talking about.
Does that make any sense, or does any one who may be able to articulate it better understand what I'm referring to?
Edit: I realize after posting that this wouldn't create a blended signal, but a hotter signal being fed into the other channel. Not really what y'all are talking about.
SCS,
i dont think you can do that on a channel switching amp without horrible consequences. those "four input" amps ala Marshall Plexi, were essential a single channel amp that happened to have four means of plugging in.
brad can go into better detail than i, but suffice to say, a channel switching amp is a whole other beast.
i dont think you can do that on a channel switching amp without horrible consequences. those "four input" amps ala Marshall Plexi, were essential a single channel amp that happened to have four means of plugging in.
brad can go into better detail than i, but suffice to say, a channel switching amp is a whole other beast.
