I pulled this quote from the '5EC mod' thread and I'd like to explore this a bit more.
phsyconoodler wrote:I cathode bias many of my D style builds and don't use the local feedback in those amps.It makes them nice and loose.The OD is really nice to my ears.
I recently built a 4 bottle 6CA7 cathode biased D style amp and the cleans are spectacular.The OD is pretty loose and does controlled feedback really nicely.
I'm a big fan of cathode biasing these amps.It loosens them up quite a bit.I use mostly NOS tubes however,and I pump the current to them.
That might kill some new production tubes.
I like a fixed bias amp too,but the cathode biased ones are pretty killer for blues based clean tones.
Last night at a local jam,two of my amps were on stage.One was the 4-6CA7 combo and the other was a 50 watt,2-6CA7 head on top of a 4-12 marhsall cab.The 4 bottle unit was spectacular with pushed cleans and the 50 watter was killer distorted.
I played my modded Vibrolux(fender til the end!)with my 72 Deluxe Tele.
I must admit that the 4 bottle amp ruled the roost last night.Fat,fat,fat was the order of the day.Killer leads for 'the thrill is gone'.The owner used a Tom Anderson Cobra.Wow! What a nice guitar!
What other mods have you guys tried that turned your D-style amp into a Blues machine? Low plates, no LNFB, cathode bias, tone stack tweaks? Is the Bluesmaster a Blues master?
I'd love to hear some down home Blues clips, too. Jazz is cool and all, but I'm a Blues guy. The best I've heard are the Red Plate clips from Henry's site. If I didn't enjoy the DIY so much, I'd order me up a Red Plate special!
"The blues is the roots, the rest is the fruits." - Willie Dixon
Sonny ReVerb wrote:I pulled this quote from the '5EC mod' thread and I'd like to explore this a bit more.
phsyconoodler wrote:I cathode bias many of my D style builds and don't use the local feedback in those amps.It makes them nice and loose.The OD is really nice to my ears.
I recently built a 4 bottle 6CA7 cathode biased D style amp and the cleans are spectacular.The OD is pretty loose and does controlled feedback really nicely.
I'm a big fan of cathode biasing these amps.It loosens them up quite a bit.I use mostly NOS tubes however,and I pump the current to them.
That might kill some new production tubes.
I like a fixed bias amp too,but the cathode biased ones are pretty killer for blues based clean tones.
Last night at a local jam,two of my amps were on stage.One was the 4-6CA7 combo and the other was a 50 watt,2-6CA7 head on top of a 4-12 marhsall cab.The 4 bottle unit was spectacular with pushed cleans and the 50 watter was killer distorted.
I played my modded Vibrolux(fender til the end!)with my 72 Deluxe Tele.
I must admit that the 4 bottle amp ruled the roost last night.Fat,fat,fat was the order of the day.Killer leads for 'the thrill is gone'.The owner used a Tom Anderson Cobra.Wow! What a nice guitar!
What other mods have you guys tried that turned your D-style amp into a Blues machine? Low plates, no LNFB, cathode bias, tone stack tweaks? Is the Bluesmaster a Blues master?
I'd love to hear some down home Blues clips, too. Jazz is cool and all, but I'm a Blues guy. The best I've heard are the Red Plate clips from Henry's site. If I didn't enjoy the DIY so much, I'd order me up a Red Plate special!
My experience with Dumble stem from
- a (50W) low plate #124 clone, 6L6 and
- ODS Highplate ODS w. both HRM and NON HRM preamps with EL34
I believe that both amps can do blues very nicely. I play tele's or strats (with a SD twangbang pickp in th bridge postition) IMO both guitars do Albert collins nicely on the bridge pu if you play hard on the strings near the bridge.
The phase inverter can really change the tone of these amps.Dumbles PI values bias the PI tube rather cold,using an 820 ohm resistor rather that Fender/Marshall's 470 ohm.Then the tail resistor/feedback resistor is different too.
I built one with a Marshall PI and presence circuit and it basically was a Marshall.The Dumble charm was lost.But....it was a mighty fine sounding amp!
No I can't imagine much difference from 470 ohm to 510 ohm.
I put the complete PI and presence circuit from a 2204 Marshall in one amp.
It sounded so much like a Marshall it was uncanny.But I wasn't wanting to build a Marshall,so it came out.
I did try adding a boost circuit with an extra relay that lifted the negative feedback.The amp was instantly turned into a rock monster.The volume and distortion boost was massive.
I think anyone who has built a few D style amps can attest to the lack of low end compared to a Marshall of Fender amp.The negative feedback is a huge part of that.But having too much bottom end is an issue a lot of players want to get rid of.Enter Dumble with an amp that cuts through the mix easily.He knew that losing some low end and boosting the mids would do it.
