Converting a blues deluxe reissue...

apostlegato

Member
2008-01-24 12:15 am
What kind of conversions can be done at low cost to my blues deluxe reissue? I really would like a bassman sound if possibe. I was considering building a 56fa from scratch, but if it may be better to convert what I have already. Any input would be greatly appreciated.
Thanks,
Mike
 

DaveMcLain

Member
2007-10-03 1:07 am
I have a customer with one of those amps, his is the original Blues Deluxe amp and I've done a few things that have helped the sound quite a bit in our opinion. I switched the amp from 6L6's to 6V6's and that was a good change, it lowered the wattage and gave it a better overdrive sound at a more reasonable level. Next up we changed the speaker, right now he has a Little Texas in there which is ok.

My gripe with these little Fender amps that they are just voiced too dark. It's like they are trying to make a little amp sound like a big amp rather than a little amp that sounds good. Just my opinion but this guy also had a Pro Junior that was voiced very similar in the stock configuration. I changed the speaker to a New Sensor alnico 20 watt 12 inch and it sounded WAY better. I think that speaker would be a good choice in a Blues Deluxe as well with the 6V6 output tubes, it'll really sing.
 

apostlegato

Member
2008-01-24 12:15 am
Thanks Dave,
I may try that. Is there a way though that I could turn this amp into a twin or bassman? I know would have to add a few tubes and take out the circuit board and put in a handwired circuit. How easy would this be? Does anyone have instructions on how to do this?
 
It can be done, but that would be like building a whole new amp! What is it exactly that you don't like about it? I've had one of these since 1998 and I aways found it quite versatile, especially with a Strat. What kind of output tubes are you using? You may want to do some tube rolling and hotter/colder bias experimenting before you start to do any drastic mods. What is the bias set at now? Fender recommends setting it at 60 mA, but I find that too cold. Setting it around 70 - 80 mA will make it sound a tad warmer. If that doesn't work, you can play with the NFB or change the speaker to something brighter/darker.
 

DaveMcLain

Member
2007-10-03 1:07 am
I agree, I'd try doing some tweaks instead of building a whole new amp out of the Deluxe because it can be made to sound pretty cool. For instance, I'd try some different preamp tubes and or a 12AT7 as a driver, experiment and see what sort of sounds you can get. Experiment with a different speaker. I think you'll find that a few little things could have you liking the amp a LOT more than a stocker.
 

apostlegato

Member
2008-01-24 12:15 am
Thanks Johnny. I havent tested the bias yet. But I will check it and adj to 70 - 80 mA like you said see how it sounds then. It has the original
GT blue labels output tubes in it. Its about a year old. Oh and BTW its a blem from musicians friend :cannotbe: Which is probably why it doesnt sound that good. Thats part of the reason I want to build a new one. Im not sure what the blemish is. I dont think its cosmetic because evertything looks good on it. With the info thats its a blem would your suggestions still the same.
Thanks again. I really appreciate the help.
 

apostlegato

Member
2008-01-24 12:15 am
DaveMcLain said:
I changed the speaker to a New Sensor alnico 20 watt 12 inch and it sounded WAY better. I think that speaker would be a good choice in a Blues Deluxe as well with the 6V6 output tubes, it'll really sing.

Which brand of 6V6s would you recommend?
What speaker would you recommend that would work good with
both the 6L6s or 6V6s (so I could change back to 6L6s if I wanted)


TubeHead Johnny said:
It can be done, but that would be like building a whole new amp! What is it exactly that you don't like about it? I've had one of these since 1998 and I aways found it quite versatile, especially with a Strat. What kind of output tubes are you using? You may want to do some tube rolling and hotter/colder bias experimenting before you start to do any drastic mods. What is the bias set at now? Fender recommends setting it at 60 mA, but I find that too cold. Setting it around 70 - 80 mA will make it sound a tad warmer. If that doesn't work, you can play with the NFB or change the speaker to something brighter/darker.

well the bias voltage is set at 73 mV It was at 71 mV and I adjusted it by ear and liked 73 a little better(I like the way it breaks up better) How do I adj the NFB? I would probably say that it gets kinda muddy or dark in the bass to low/mid notes especially when strumming hard or with overdrive, could this be the speaker?

DaveMcLain said:
I agree, I'd try doing some tweaks instead of building a whole new amp out of the Deluxe because it can be made to sound pretty cool. For instance, I'd try some different preamp tubes and or a 12AT7 as a driver, experiment and see what sort of sounds you can get. Experiment with a different speaker. I think you'll find that a few little things could have you liking the amp a LOT more than a stocker.

How will the 12AT7 change it?
 
Here are some photos of a re-wire of a Fender amp that replaced the circuit board with an eyelet board.

http://www.naturdoctor.com/Chapters/Rodgers/ReWire.html

In this case, the amp had been repaired several times in the last year, which annoyed the owner. He had several older eyelet board amps that hardly ever needed repair, and when they did they were fixed quickly.

>> How will the 12AT7 change it?

The AT7 has slightly lower gain but delivers a lot more current, which makes it a great choice for a phase inverter. The sound and breakup are different.

>> I adjusted it by ear and liked 73 a little better

Slightly higher bias reduces crossover distortion, which makes the amp sound better clean and breakup earlier at the expense of tube life.

>> What speaker would you recommend

There are tons of choices!
My personal favorites are EV SRO (weighs a ton!) and Jensen P12R (for shimmering highs).
 
As far as 6V6's go there are numerous choices of current production stuff. This amp has the EH 6V6's which seem to work well and sound good. I don't know how something like a JJ would be in there but I would say they would be nice based on my experience with using them in a few other amps. I can't remember where I biased them current wise but it was very easy to do and switching back and forth with the 6L6 would be super easy. I've never tried the 6V6 swap in any Marshall amps but I'm thinking I might try it sometime just for fun. In the Marshalls that we use in the band right now I'm using the KT66HP(Saratov produced from Groove Tubes) and they are awesome. I wonder what a 6V6 would do? We use a power attenuator 99% of the time anyway...

The 12AT7 is just a different sound in the phase inverter and something to experiment with since it requires no circuit modification, just plug and play. See if you like it better or not as well as the stock 12AX7 in that position. Whatever works for your playing. Trying a few different 12AX7's in position 1 in particular could help to fine tune the sound. Most of the time in rather subtle ways but that can be a fun way to experiment again no mods are required just a few different 12AX7's. Try the JJ, Chinese or anything you can find, what sounds good is good.

As far as speakers go, this guy has an Eminence Little Texas in the amp which seems to be ok. In lower power stuff I really like the 12 inch alnico magnet 20 watter that Electro Harmonix offers. It's not very expensive and in something like a Deluxe seems to sound really good with a great tone and smooth breakup. It's much better in my opinion than the stock speaker in something like the Deluxe Reverb reissue. With that said in the Blues amp it would probably be very cool but I've not tried that combination. When running with 6L6's I don't know how long it would hold together but I'd bet it would sound great while it lasted, who knows, it might last for years.

I'd say to get a couple of speakers and try them, see what you like best. Generally something low powered(what the amp really needs) isn't all that expensive. Some low wattage ceramic magnet speaker could be very cool too. Experiment it's fun and you'll learn a lot about guitar sounds.
 
I replaced the stock Eminence speaker with a C12N Jensen and I think that it is definitely worth the while. Replacing the 6L6's with 6V6's? You would have to re-bias, and biasing is not an easy thing to do. I wonder if re-biasing could be avoided by changing the wiring of the power stage from fixed-bias to self-bias. We would still have a push-pull amp and therefore the OT would be valid, and less power with the 6V6's -without having to re-bias. If anybody has ever tried anything of this sort, I would very much appreciate to hear from him. Cheers, Beni.