New Build: Ceriatone Replica OTS 50W
Moderators: pompeiisneaks, Colossal
Re: New Build: Ceriatone Replica OTS 50W
Had a very successful checkout with the amplifier today with my amp technician Aubrey Page. Doing a very thorough pass through, we caught one ground wire from the speaker jacks to ground that was missing and got one in place. The only other problem we had was the 15K carbon comp resistor on the bias pot that was unstable so we replaced that.
Once we validated all the voltages and worked our way up to having all the tubes in, it was time to fire it up. Everything seemed fine but with a 60 cycle hum. Aubrey asked if the heater voltage from the PT had a center tap and sure enough it did not. A couple of resistors later to ground to create a CT and we fired it up again and the hum was gone
Everything is working beautifully. Since my MIDI cable did not show up in time, we were not able to try the footswitch.
In the coming days I plan to post pictures and results with testing the footswitch.
Thanks again to all who helped me with making this project such a great success
Dave
Once we validated all the voltages and worked our way up to having all the tubes in, it was time to fire it up. Everything seemed fine but with a 60 cycle hum. Aubrey asked if the heater voltage from the PT had a center tap and sure enough it did not. A couple of resistors later to ground to create a CT and we fired it up again and the hum was gone
Everything is working beautifully. Since my MIDI cable did not show up in time, we were not able to try the footswitch.
In the coming days I plan to post pictures and results with testing the footswitch.
Thanks again to all who helped me with making this project such a great success
Dave
- martin manning
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- Location: 39°06' N 84°30' W
Re: New Build: Ceriatone Replica OTS 50W
Great! Overall sounds like it went pretty smoothly considering you mixed two different layouts. You aren't the first to miss a speaker output or filament circuit ground.
Re: New Build: Ceriatone Replica OTS 50W
Well the MIDI cable showed up yesterday after arriving home after the amp checkout. Looks like my perspective was backwards on the female DIN on the amplifier making things backwards on the footswitch. Rather than messing with the amp I re-wired the footswitch and everything is working there as well!
This thing is ready to Rock, Robben Ford, Larry C etc...this is literally a dream come true.
Few questions around the switching:
1. The Preamp Boost I believe bypasses the EQ stack and the amp acts accordingly, the EQ changes make no difference. Does it add anything?
2. The Deep switch does seem to make any noticeable difference. What should I be hearing?
3. The Jazz / Rock switch also has a noticeable gain and EQ difference. Is there a way to get those more gain balanced?
Thanks
Dave
This thing is ready to Rock, Robben Ford, Larry C etc...this is literally a dream come true.
Few questions around the switching:
1. The Preamp Boost I believe bypasses the EQ stack and the amp acts accordingly, the EQ changes make no difference. Does it add anything?
2. The Deep switch does seem to make any noticeable difference. What should I be hearing?
3. The Jazz / Rock switch also has a noticeable gain and EQ difference. Is there a way to get those more gain balanced?
Thanks
Dave
Re: New Build: Ceriatone Replica OTS 50W
Martin when you say mixing two layouts do you mean schematics? The reason I ask is I know the schematic we were working with did not exactly match the Ceriatone layout. Can you tell me which two layouts you are referring to?martin manning wrote: ↑Sun Jul 23, 2017 10:33 am Great! Overall sounds like it went pretty smoothly considering you mixed two different layouts. You aren't the first to miss a speaker output or filament circuit ground.
My amp tech has also been commissioned by a client to build an ODS with a 4 relay footswitch so he can control all the switches in the front. He is designing his own board to do all that. Quite impressive. But I was going to pass on the information on the two layout blend so he could marry the two together if it helps based on what he and I worked on yesterday.
Thanks,
Dave
Re: New Build: Ceriatone Replica OTS 50W
FINAL PHOTOS
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- martin manning
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Re: New Build: Ceriatone Replica OTS 50W
Maybe mixing a layout and a schematic... I think you were mostly following the C-tone 100W high-plate layout, but the ODS 124 (low plate) Skyliner schematic was referenced a number of times. They are close, but not identical. A layout is a drawing showing the physical arrangement of components and connecting wires corresponding to a particular schematic. The schematic shows components and electrical connections without (necessarily) any regard to the physical arrangement. There are some notes on the 124 schematic indicating ground locations, which differ from the C-tone layout.
Re: New Build: Ceriatone Replica OTS 50W
Thanksmartin manning wrote: ↑Sun Jul 23, 2017 4:19 pm Maybe mixing a layout and a schematic... I think you were mostly following the C-tone 100W high-plate layout, but the ODS 124 (low plate) Skyliner schematic was referenced a number of times. They are close, but not identical. A layout is a drawing showing the physical arrangement of components and connecting wires corresponding to a particular schematic. The schematic shows components and electrical connections without (necessarily) any regard to the physical arrangement. There are some notes on the 124 schematic indicating ground locations, which differ from the C-tone layout.
- martin manning
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Re: New Build: Ceriatone Replica OTS 50W
Doesn't add anything, just takes less away ;^).
You have a deep switch? The C-tone layout shows Bright, Mid Boost, and Rock/Jazz, with PAB on the back or foot switch.
I suppose you could modify the tone stack to get more volume in the Jazz setting, but most people just take it for what it is. Some like it, but most don't. Try using the FET input to boost the volume.
Re: New Build: Ceriatone Replica OTS 50W
Well the front panel says Deep but the Layout says Mid Boost. Oh Well...maybe the lack of Mids is Deep - I don't know LOLmartin manning wrote: ↑Sun Jul 23, 2017 5:18 pmDoesn't add anything, just takes less away ;^).You have a deep switch? The C-tone layout shows Bright, Mid Boost, and Rock/Jazz, with PAB on the back or foot switch.I suppose you could modify the tone stack to get more volume in the Jazz setting, but most people just take it for what it is. Some like it, but most don't. Try using the FET input to boost the volume.
Dave
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- martin manning
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Re: New Build: Ceriatone Replica OTS 50W
You should definitely hear the mid boost when it is engaged... Looks like you are missing the jumper across the bottom two lugs.
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Re: New Build: Ceriatone Replica OTS 50W
Well that's an easy one to miss on the layout. WOW. Thanks Martin!martin manning wrote: ↑Sun Jul 23, 2017 8:02 pm You should definitely hear the mid boost when it is engaged... Looks like you are missing the jumper across the bottom two lugs.
Dave
- pompeiisneaks
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Re: New Build: Ceriatone Replica OTS 50W
I'll delete it, I think only mods can delete them, just edit the post to say only something like 'please delete, duplicate' or whatever and I'll clean them up
~Phil
tUber Nerd!
Re: New Build: Ceriatone Replica OTS 50W
Added the one wire missing on the Mid / Deep switch and everything is working now. Added the logo on the front. Here she poses.
Dave
Dave
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Re: New Build: Ceriatone Replica OTS 50W
Sharp looking amp, hope it sounds as good.
Mark
Mark