I was about to CAD up a chassis and have some built and thought better of it. I'm probably going to build a few different designs first and have some local players put some miles on them before deciding which one to market and the idea of rolling my own for something so complicated doesn't appeal to me at all.
1. Has anyone on the board made group buys of chassis' available or is there someone who sells them other than the ebay asian connection?
2. For those of you who have experience with the numerous designs which is your favorite and what would you chose if you had to chose one?
3. Is there a glossary of Dumble terms & acronyms anywhere as a sticky? Seems teh more I think I have them down the less I do!
Thanks,
Craig
Ready for first build, a few ?'s
Moderators: pompeiisneaks, Colossal
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collinsamps
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Re: Ready for first build, a few ?'s
Good luck withe the builds.
My favorote is the 90's HRM. It's fairly low gain compared to the 70's with 100k/1.5k Rp/Rk but smooth and refined. The hybrid with high plates and no HRM would be my second favorite. I'm not a huge Blues Master fan like many other here, just a personal choice, great sounding amps but not my sound.
I don't know of any glossery of terms but search out a few.
HRM = Hot Rubber Monkey and refers to the amp with a post overdrive tone stack using trim pots. There's other changes to the amp as well. Check out the ODS101 schems on the files page.
Blues Master = an ODS with different tone stack and PI.
High plates = the 90's version with Rp/Rk 220k/3.3k and 180k/2.7k on V1 and 180k/2.7k and 120k/2.2k.
Hybrid = 70's type amp with high plates.
PAB = Preamp Boost. A relay that switches the tone stack out of the ckt for more gain.
Have fun.
My favorote is the 90's HRM. It's fairly low gain compared to the 70's with 100k/1.5k Rp/Rk but smooth and refined. The hybrid with high plates and no HRM would be my second favorite. I'm not a huge Blues Master fan like many other here, just a personal choice, great sounding amps but not my sound.
I don't know of any glossery of terms but search out a few.
HRM = Hot Rubber Monkey and refers to the amp with a post overdrive tone stack using trim pots. There's other changes to the amp as well. Check out the ODS101 schems on the files page.
Blues Master = an ODS with different tone stack and PI.
High plates = the 90's version with Rp/Rk 220k/3.3k and 180k/2.7k on V1 and 180k/2.7k and 120k/2.2k.
Hybrid = 70's type amp with high plates.
PAB = Preamp Boost. A relay that switches the tone stack out of the ckt for more gain.
Have fun.
Re: Ready for first build, a few ?'s
At $65, the Ceriatone chassis is probably good enough to test the waters. As for "favorite" circuits, you'll probably find as many opinions as there are builders. My personal amp is a Bluesmaster, but I have always loved the non-HRM with high plates.
If you're going to market these amps, it would be a good idea to build as many versions as you can so you know how to match the correct circuit with the player.
If you're going to market these amps, it would be a good idea to build as many versions as you can so you know how to match the correct circuit with the player.
Re: Ready for first build, a few ?'s
Craig,
I looked through your website, nice looking amps, nice variety designs. Are you going to the NY amp show? I'd love to see your stuff.
On another note, I see you use a lot of PS 715, Mallory 150 and silver mica caps. Unfortunately these selections don't work well in a Dumble. These amps like PS6, MPP and some other poly caps as well as ceramics for pF range caps. I've had some inconsistencys with the 6PS but when they work, they work great. The Xicon MPP and MP's are more consistent IMHO and sound great. NTE poly's also seem to work well.
Also remenber the plates really like quality metal film. Most of us use Vishat-Dale RN65's but they're not rohs so that might not work for you. Experiment in this area. I tried some xicon metal film, then moved to RN65's and the change was dramatic. Carbon comp were actually better than the xicon's but the RN65's were the clear winner.
I looked through your website, nice looking amps, nice variety designs. Are you going to the NY amp show? I'd love to see your stuff.
On another note, I see you use a lot of PS 715, Mallory 150 and silver mica caps. Unfortunately these selections don't work well in a Dumble. These amps like PS6, MPP and some other poly caps as well as ceramics for pF range caps. I've had some inconsistencys with the 6PS but when they work, they work great. The Xicon MPP and MP's are more consistent IMHO and sound great. NTE poly's also seem to work well.
Also remenber the plates really like quality metal film. Most of us use Vishat-Dale RN65's but they're not rohs so that might not work for you. Experiment in this area. I tried some xicon metal film, then moved to RN65's and the change was dramatic. Carbon comp were actually better than the xicon's but the RN65's were the clear winner.
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collinsamps
- Posts: 223
- Joined: Fri Mar 06, 2009 1:51 pm
- Location: North Carolina
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Thanks guys
Bob & Normster, thanks for the info, very valuable stuff. I'm not making the NY show Bob but hope you enjoy it.
I'll eventually offer all designs(3 anyway) but want to cut my teeth on one platform until I know the amp inside and out. As for components I've already set aside some tasty choices for the prototype and will be interested to see the outcome. I've been having my own caps built for the past year or so and have had really good results in other circuits (my kensington & eastender have pretty much evolved into new territory as a result, or at least it's a new option for those who want something great sounding beyond traditional). As for metal films I do use a lot of vishay dales and concur with you 100% on the difference. I only do carbon films or comps anymore when they are asked for.
I'm also tossing cosmetics around, I know the original look is a lot of it's appeal but here must be 6-7 builders at last count offering it that way. I'll probably mix it up some there as well.
Thanks again and I'm still hoping around here learning as I go. so nice to see a community exchange info on such a professional level.
I'll eventually offer all designs(3 anyway) but want to cut my teeth on one platform until I know the amp inside and out. As for components I've already set aside some tasty choices for the prototype and will be interested to see the outcome. I've been having my own caps built for the past year or so and have had really good results in other circuits (my kensington & eastender have pretty much evolved into new territory as a result, or at least it's a new option for those who want something great sounding beyond traditional). As for metal films I do use a lot of vishay dales and concur with you 100% on the difference. I only do carbon films or comps anymore when they are asked for.
I'm also tossing cosmetics around, I know the original look is a lot of it's appeal but here must be 6-7 builders at last count offering it that way. I'll probably mix it up some there as well.
Thanks again and I'm still hoping around here learning as I go. so nice to see a community exchange info on such a professional level.
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collinsamps
- Posts: 223
- Joined: Fri Mar 06, 2009 1:51 pm
- Location: North Carolina
- Contact:
forgot to say
To all who are in the chassis or reproduction game who read this and fear competition on chassis' or builds etc...........let me put your mind at ease. I'm only looking for a few test bed chassis' and not going to produce the standard style. I guess the prototypes will be sold as is, but when I do field the amp it won't look like a typical ODS style amp. So rest easy all.
Thanks
Thanks