18watt Liverpool build *** IT'S ALIVE!!!! ***

[DerStever]

Ok, Before I put this thing back to an 18 watt Marshall Clone - I would really like to make sure its not me missing something so here are some pix - I'd really appreciate any help you can give me on this - I'm too close to it.

Its using old Mullard and Telefunken 12AX7s and JJs on the output. Heybour 18watt GDS trannys and a UK Vintage 30 Celestion in the box.
Symptoms are cold fairly clean and bright sounding until you get to 8 where it gets distorted similar to my Express but no where near as nice sounding - most of the highs drop off here and it gets dark and somewhat muddy. I'd really like it to do the opposite and stay warm and dark until you get to the distortion - then get glassy.

The only thing I can think of is jumping the center and left tab on the presence pot - in Ceriatones drawing its not but in the new ones it is.
I'm using a 250pf in the bright cap also.

Please be tolerant of the wiring - this amp has been wired and rewired several times - and modifed and abused - amazingly its very very quiet - no hiss or noises until you play it..... but an AllynMey Job its not .....

Blue wires are Plate (except the little piece on the signal part of the board) the Blue and White are Heater - Red is B+ - White is signal as is Shielded - Yeller is Cathode. Black is ground and Green is the Presence. All Cap values are either exact or in the case of the bypass I use 25x50 instead of 22x50.

[UR12]

Woohoo. Got the new 15 watt Liverpool trannys in yesterday for my 15 watt Liverpool combo build. I had Heyboer take the stock 18watt PT and made it with a 300v and a 260v winding. Everything else stayed the same and they barely got all the windings and leads to fit the 18 watt tranny dimensions. These are the exact dimensions to fit an 18watt combo chassis. The OT is also the same physical size but was wound to 10.4k. I got 2 sets and am planning on trying maybe a 20watt express combo with 6v6s using the 300v tap maybe later this winter. Unlike the 18watt this will be a single channel amp with power scaling. Actually the only thing it will share with a 18watt Marshall is the combo cabinet . Everything else will be Trainwreck inspired

[dartanion]

VERY COOL DANA!!!

Keep us abreast of the details.

huh huh...he said breast

[DerStever]

As a final note on this - I put amp back to an 18watt although now I've got some wierd problem going on which Ive never experienced. I never could get it to do what I wanted it to - it may be that Graydon's design doesn't lend itself well to T-Wrecking.

I ordered some parts for a real Liverpool instead ..... Good luck Dana it sounds like you'll get it to work right!

[dartanion]

Layout for a wreck is pretty critical.

What's the issue with it now?

[dartanion]

Cut the boards out over the weekend. Need some time to drill and set the eyelets. Hope to squeeze that in tonight.

[DerStever]

Dart - not sure if you were addressing me - but I did redo the entire board like the Ceriatone drawing - what I ended up with was a rather brassy distorted amp - the distortion wasn't as smooth as my express and I compared apples to apples using the same speaker cab. When I did the Liverpool changes it was better but still not what I wanted - frankly I've got the 18 watt back almost where it was and it sounds much better than what I was dealing with before - less distortion but has that Marshall vibe - which I plan to make nicer with some cap tweaks - I have a certain sound in my head for this and I'm going to get there with it - or close.

The issues were a parasitic and a couple of bad solder joints which I found and fixed. Its always something stupid like that which trips you up.

[harryk]

DerStever! I have been struggling with samekind of voicing problems with my Liverpool 2xEL84 project and I am really considering to go also Marshall 18W way. Can you tell what 18W channel you are aiming to do? Somebody says that tremolo channel is the best one in this amp and someone says that the best is the channel with only volume and tone controls. I have heard not so good comments of that TBM channel in this amp. I am pretty disappointed with my Twreck skills at the moment. That is why 18W is one way to go. With respect Harry

[UR12]

DerStever! I have been struggling with same kind of voicing problems with my Liverpool 2xEL84 project and I am really considering to go also Marshall 18W way. Can you tell what 18W channel you are aiming to do? Somebody says that tremolo channel is the best one in this amp and someone says that the best is the channel with only volume and tone controls. I have heard not so good comments of that TBM channel in this amp. I am pretty disappointed with my Twreck skills at the moment. That is why 18W is one way to go. With respect Harry

I am going to attempt to answer this question regarding making the 18watt into a TW style amp. I know a lot of people have tried and not been happy with the results. IMHO I really don’t think that you can just put a Liverpool preamp in front of a 18watt power section and get it to sound and play like a Liverpool. The problem with taking an 18watt Marshall amp and turning it into a TW IS the power section.

The voltages are higher in the 18watt vs the Liverpool. This means you will be driving the EL84s harder , and they tend to get fizzy when cranked. The lower voltages of the Liverpool allows it to distort sooner but stay creamy without the fizz.
The PI uses different values and provides more gain than in he Liverpool.
The PI in the 18watt has two inputs that are 180 degrees out of phase with each other.
Since the two channels are out of phase you can’t implement negative feedback which means no Presence control and this takes away from the Liverpool voicing
The OT has a different primary impedance
The power amp uses different value grid resistors and screen resistors

I guess what I am trying to say is that if your goal is to come away with a lower power version of a Liverpool sounding amp, your not going to get an amp that does that. If you have to change all of the above stuff then you’re not using a Marshall power amp and PI circuit any more and why even bother talking about the 18watt Marshall. If you keep all of the above then you won’t have a Liverpool or even an amp that has any Liverpool properties but some hybrid in between Frankenstein kind of creation.

IMHO what needs to happen is to forget about the 18watt Marshall circuitry and concentrate on building a true single channel Liverpool circuit with the right voltages, values and OT. I have already gotten the Trannys custom made to fit a Marshall style Combo chassis and will start a new thread regarding my 15 watt Liverpool combo build as soon as I get time to start a new project. (I’m still tweeking on the 2 channel amp at the moment.)

In regards to the TMB not sounding good, I think when they are setup right they sound awesome. If you really want a cool 18watt amp then take Richie’s 36 watt preamp and install it in place of the standard 18watt TMB and then you got something very cool. Just my 2 cents. It’s a shame this conversation couldn’t be carried out on 18watt any more as it would be considered off topic.

[harryk]

Dana I highly appreciate your words and want to learn to tweak my Liverpool until it sounds right to my ears. My present version is standard Liverpool except 2xEL84 tubes and higher plate+screen voltages in power tubes. Preamp is according Mark Abbott drawning and voltages. I have one PT lying with 2x250V/110 mA. Should I change this PT to lower plate and screen voltages in power section to get closer original Liverpool. It is very difficult to buy a PT with 2x260V in Finland. If you want that you have to order it customized which is expensive. The more I watch Glen clip in Yotube, the more I know that I want to make one amp like his. Regards Harry

[UR12]

Dana I highly appreciate your words and want to learn to tweak my Liverpool until it sounds right to my ears. My present version is standard Liverpool except 2xEL84 tubes and higher plate+screen voltages in power tubes. Preamp is according Mark Abbott drawning and voltages. I have one PT lying with 2x250V/110 mA. Should I change this PT to lower plate and screen voltages in power section to get closer original Liverpool. It is very difficult to buy a PT with 2x260V in Finland. If you want that you have to order it customized which is expensive. The more I watch Glen clip in Yotube, the more I know that I want to make one amp like his. Regards Harry

Harry
I would rather have the 250v tranny than the 290v in the 18watt. I would think the 250 would get you in the right ball park for EL84s. The interesting thing to me is that you refer to the amp that Glen used in his youtube video. That was an Express, not a Liverpool and while they share a common preamp the pi and power amp is different (EL34s) and they sound and play a little different. I would think you would get closer to a Express type tone like Glen's by using a 6V6 output stage and Express PI values instead of the EL84s. Of course if you run 6V6s then you can get your Tranny voltages back up to around 300vac /250ma so I guess it depends on what you are after.

[harryk]

Hi Dana! I know that it was Express and not Liverpool but I presume that they are some relatives soundwise. To me 2xEL34 is too much volume after 30 years playing in rock bands. You can always use some attenuator or power scaling but I try to get the sound I like with smaller tubes and volumes. I have used 6V6 tubes with good results in many projects, but now I wanted something else. I just red of Paul Ruby tweaks to Express preamp and I try them to my Liverpool project. In this age of 51 years you have a lot time in the evenings (no girl hunting or night clubs etc.) to tweak these little beasts. I will change PT to 2x250V. By the way if you like to see my amps, please look at www.bluetone.fi Regards Harry

[UR12]

Hi Dana! I know that it was Express and not Liverpool but I presume that they are some relatives soundwise. To me 2xEL34 is too much volume after 30 years playing in rock bands. You can always use some attenuator or power scaling but I try to get the sound I like with smaller tubes and volumes. I have used 6V6 tubes with good results in many projects, but now I wanted something else. I just red of Paul Ruby tweaks to Express preamp and I try them to my Liverpool project. In this age of 51 years you have a lot time in the evenings (no girl hunting or night clubs etc.) to tweak these little beasts. I will change PT to 2x250V. By the way if you like to see my amps, please look at www.bluetone.fi Regards Harry

I agree that the Express is loud and like you my poor ears are 53 years young. 15 -18 watts is still pretty loud in my book. I haven’t built a amp over 50 watts in some time. Even though the Express shares the same preamp it has been my experience that while they do share some attributes they don’t sound exactly alike. Each one has it’s own little flavor, but the two things they share is the singing sustain and the ability to go from clean to mean with the vol on your guitar. What voltage are you running right now? Let us know how Paul’s tweeks work out for you.

I do envy you with all that time on your hands. If I’m not building amps I am playing with my car restorations (I restore old VWs and build kitcars) I also help my son’s band out from time to time doing sound for them in clubs that require a little more effort or where they don’t have a soundman on staff. This gets me and my wife out in the clubs every now and then. I’ll be doing a show with them Friday night here in a local pub. You can check out their myspace at http://www.myspace.com/tencarplie. (I have to warn you, they are a weird bunch) My son's the drummer

You have done a beautiful job on your amps at your website. Absolutely awesome work! Love the snake skin cab!!

[harryk]

Heh! this is getting very nice project to meet new nice people in this forum. Everytime I come here I learn a lot despite I have built tube amps a long long time. My time is also limited but if you relly love something, you always fins some time to it. My missio is to try to retire from my everydat job within 5 years and devote myself to guitar playing, tube amp building, tennis, fishing and travelling with my wife.

I tried Paul`s modifications and all touch responsivness disappeared. Then I changed bass pot to variable, slope resistor from 100 kohm to 47 kohm and treble cap from 50 pF to 500 pf. Result was awful sounding amp that has to be tweaked with some new ideas. Any new ideas??? Reagrds Harry

[DerStever]

harryk,

I'm using the GDS basic design for TMB on my 18 watt clone with a Vintage 30 speaker - tubes are Mullard used 12AX7s and Telsa EL84s - I put the amp back to the way I had it before which was an 18 watt with NFB and Presence - 4 inputs - unlike stock 18 watts this has more sizzle and more controllable mids. I have tweaked the caps and use a mix of Orange Drops and Sozos to get a sweet glassy clean sound and when turned up a nice creamy smooth Marshall distortion with some high end sparkle- its a really nice tone with my strat. A balancing act between getting the glass treble from the presence / and keeping it under control in the PI and Tone stack. I've tried a bunch of different cap combinations in the PI and always come back to this one that I found after days of trial and error and A/B ing different values and manufacturers.

I use .047 Sozos in the PI input - .02 P6s ODs in the PI Output - the Tone Stack is .1 .047 150K Sozos respectively. .1 OD on the presence control with 100K NFB resistor. Its either a 10 or 25K pot.

I do want to do the Volume Scaling thing on this Dana so whenever you have that circuit done please let me know - I also ordered parts for a Liverpool and plan to do the same there - if you don't have the stuff for that I'll get the kit from Oconnor. Let me know where you are at with this please - the 18watt is my church amp and I'd like to be able to scale it back so I don't get the hairy eyeball from the worship director