Moderators: pompeiisneaks, Colossal
I've tried svetlana6L6, JJ6V6 and JJEL34's in there. No luck. I like the mild drive, just when it is breaking but not the full blast sound - souns like a pedal to meI wouldn't give up on your express, they are very picky about what tubes sound good in them. Phil
Cab is DIY 2x12 with one Red White and Blues connected. Guitar is DIY http://koti.welho.com/mtiilama/DIY%20Guitars.htm 'Julia' with Schaller bridge humbucker - works wonderfully with the nonHRM witth 6L6's in it.dogears wrote:Hey Mat,
What speakers? Also, what pickups? I tried an axe with an alnico V bridge and it was shrill. Going back to any of my guitars totally fixed the problem.
) to see if it would better by time.I didn't like my express at all with modern tubes, pre's included. Philmat wrote:I've tried svetlana6L6, JJ6V6 and JJEL34's in there. No luck. I like the mild drive, just when it is breaking but not the full blast sound - souns like a pedal to meI wouldn't give up on your express, they are very picky about what tubes sound good in them. Phil
But I will definitely get back on the express when my HRM's harshness is tamed. Maybe put the choke in the express..
I dont have money to buy nos tubes on every socketphilmanatee wrote:I didn't like my express at all with modern tubes, pre's included. Philmat wrote:I've tried svetlana6L6, JJ6V6 and JJEL34's in there. No luck. I like the mild drive, just when it is breaking but not the full blast sound - souns like a pedal to meI wouldn't give up on your express, they are very picky about what tubes sound good in them. Phil
But I will definitely get back on the express when my HRM's harshness is tamed. Maybe put the choke in the express..
But I have few euros to buy some more components 
tweaktweaktweak 
I have dpdt-switch that bypasses the d-lator from the circuit. Eaven bypassed the feel of the amp is too 'shrill' and 'hard'. It has happened twice that the sound had dissappeared complitely ? After power of and on it is working again. I must check all the solder joints again.llemtt wrote:mat
remove completely the internal D-lator from the circuit and see if things improve
and please post detailed pics of you build, it has something wrong!
Teo
Thank You, clips will follow imediatly when I get the OD to work in a right way.Congratulations on a great build.
I'll try on some of the questions.I hope some can clarifying these few points before I embark on my build.
Yes, they are 1N4007.Are the value of the diodes you used 1 amps 1000 volts ? (1N4007)
Takamishava RY5W-KWhat type, model and brand of relays are used ?
Yes.Are the yellow resistors used carbon film ?
Yes.Are the Vishay Dale RN65 metal film the brown coloured ones ?
Sorry, I don't quite get this one. The 220k's (not connected) get their bias voltage from two seperate trimmers. Yellow wire was used. Btw. What picture are You referring to ?Is the yellow wire running from the board located next to the transformer with the 56 k resistor links up to the bias point were the pair of 220k resistors join ?
Yes, I supose that is the half power switch. Sorry, dont know the values.Next to the output jack there is a switch with two resistors in parallel that are missing there values and have ?? on them. Does the switch change the amp from a 100 watts to 50 watts ? What should the value of the resistors be and how should they be hooked up in the circuit ?
No idea, I used 2n4416.On the top right hand side board is the NTE 152 a:-
1. Silicon Complementary NPN Transistor. Audio Power Amplifier, Switch.
NTE 152 OR
2. NTE152 : Silicon Complementary Transistors Audio Power Amplifier, Switch
They are 5uF electrolytic caps.On the same board what are the small blue oval components - one is located next to the 2K7 resistor - what are these components and what is there value ? Is there any brand that you use specifically for these ?
Correct (the 500pF is ceramic).On the lower board there is also a capacitor that is green in colour is this value 500 pf ? On the same board are the value of the trim pots 20 k, 1M and 250 k ?
Yes there are few groud line missing. If assume Normster has not finished this build/layout yet. Might be busy with the D-LitesOn the main board were the coupling capacitors are located are all other points that are not connected to any other components actually connected to earth ?
http://www.uraltone.com/kauppa/index.ph ... a7b19f4371Where did you get the chassis and boards from ?
PT=TV19 and OT=NSC018343What type of transformers did you use ?
Few pictures:llemtt wrote:mat
remove completely the internal D-lator from the circuit and see if things improve
and please post detailed pics of you build, it has something wrong!
Teo
not good at all, small switches do leak at high freq!!!mat wrote:I have dpdt-switch that bypasses the d-lator from the circuit.llemtt wrote:mat
remove completely the internal D-lator from the circuit and see if things improve
Thank YouThanks Mat great pics! I promised I'll study very carefully.
I have shielded wire on input to V1, V1b to volume, drive pot viper and master viper to d-lator. I read somewhere that these are good places to put the shielded, but I can change them. The amp is very silent and actually has more highs than neededAt first look I can't understand if you are using coax on the OD section, there must be 4 "at least one foot" pieces of coax
1 from v2a to drive
2 from drive to v2b
3 from v2b (tone stack out) to OD volume
4 from OD volume to relay (this one is critical!!!)
This is a mod that I tried but it did not affect the brightness of the amp either way.then I see a strange connection of a small cap between plates of P.I., I can't see if it correctly goes plate to plate (btw it should not be there because no oscillation are expected in a good ODS build)
That is exactly what I have suspected also (with my very limited skillsbut what I suspect the most is an high-freq leakage from the OD section into some other part of the circuit, can you take the OD TS board of and shot a pict? there is a critical section!!!
) Ok, here they are:Would be really nice to read the interview. Yes, I know it is too crowded but have to say that some original photos of the dumbles show that they are quite crowded themself sometimes alsoanyway you putted to much stuff in that crowded chassis -> you can't !!! HAD too was saying so (If I can recover the interview I'll send it to you)
Do You mean I should put in a bigger dpdt or take the small one away ?not good at all, small switches do leak at high freq!!!
take your solder and remove
First thing tomorrow, THANKS!llemtt wrote:Ok Mat
two things
first you need all those 4 coax in the OD section or you have to add small capacitors to achieve the same effect -> one foot of coax is something between 33-47pF, you can solder them directly on drive and OD volume pots (one cap from hot to ground and one cap from wiper to ground)
then a larger switch is better but it also leaks and since you are debugging your amp I strongly suggest to desolder and rewire your amp without the D-lator stuff but before you can try this test:
turn your OD volume completely off, then master maxed and D-lator return maxed, then play -> in case you hear something coming out from the speaker you surely have a leakage
Teo
