4-4-0 [2 NEW BUILDS WITH PICS; THE 2 WATT WRECK]

[wrsrider]

Wow, I'm sure this has been said before, but +1 to Cliff's kits. I didn't expect them to come with every little piece of hardware necessary, and especially didn't expect it to come with tubes. Very cool.

Couple of questions now: On the layout, it looks like the first two terminals on the multi-cap can are wired to the same electrical point. I assume the 40uF is intended to go to the turret on the other side of R3?

With the Heybeor xfmr, does the yellow wire = the white on the Hammond? Seems logical, but that doesn't always mean anything.

Finally, it looks like the layout and the schematic show two different orders of wiring the impedance selector switch. Schem: 1-orange 2-white and 3-green, Layout: 1-orange, 2-green, 3-white. Would someone be kind enough to tell me which color is for which impedance? Also, on a side note, on the schematic, it looks like when you are selected to the "white" impedance that your output to the speaker is inverted from the other two impedances? That seems like it could cause an issue with multi-amp setups.

Thanks Cliff!

[cliffchappell]

Wow, I'm sure this has been said before, but +1 to Cliff's kits. I didn't expect them to come with every little piece of hardware necessary, and especially didn't expect it to come with tubes. Very cool.

One of the complaints I've heard over and over about kits are that folks are disappointed that they don't come with all of the little stuff that you need to build the amp. Things like hardware, wire, etc. Once you have a few builds under your belt, you know all that, and you can plan for it. But if you don't know about it it's a source of frustration and I want to remediy that if I can. It does have the drawback of adding to the cost of the kit, and that probably accounts for low kit sales.

Couple of questions now: On the layout, it looks like the first two terminals on the multi-cap can are wired to the same electrical point. I assume the 40uF is intended to go to the turret on the other side of R3?

You are right: that's a screwup. The first 40u terminal should be connected to the right-hand side of R3.

With the Heybeor xfmr, does the yellow wire = the white on the Hammond? Seems logical, but that doesn't always mean anything.

On the Heyboer, the correct hookups are:

Orange = 16R
Green = 8R
Yellow = 4R
Black = Common

The hammond colors should be the same, but they can be anything you want. The 125 series don't have secondary wires on them, you have to put your own on them. The Heyboer detail is incorrect, whe wire called out as white should be black.

Finally, it looks like the layout and the schematic show two different orders of wiring the impedance selector switch. Schem: 1-orange 2-white and 3-green, Layout: 1-orange, 2-green, 3-white. Would someone be kind enough to tell me which color is for which impedance? Also, on a side note, on the schematic, it looks like when you are selected to the "white" impedance that your output to the speaker is inverted from the other two impedances? That seems like it could cause an issue with multi-amp setups.

Thanks Cliff!

Both the Hammond and Heyboer, for simplicity, should have been shown with the same color scheme on both the schematic and layout. I'll get that corrected later and re-post them. Sorry for the confusion.

[cliffchappell]

Duplicate post deleted.

[GainMaster]

This is a comparison of the 4-4-0 and an express clone Jose posted over at the AX84 forum.

Brian


'4-4-0 and a clone express.'
Author: Jose Echevarria (registered user: 73 posts )
Date: Fri, Nov 14th, 2008 @ 13:23

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I went to a friends studio to record an express clone and how the 4-4-0 compares to it. They both sound earily similar in the clean to mean department using the most recent schematic with the 12ay7. The only difference was the 4-4-0 has more gain at tap and the express was obviously louder pushing more air which gave it a more thumpy bass attack (those OTs are damn huge and heavy!).

We tried to replace the 12ay7 with an 12ax7 and it obviously gave it more gain. Replacing the V1 with a bugleboy 12ax7 made the amp even better and slightly more but smooth gain without the typical hi-gain gritty sound. It is definitely worth the money.

We A-B'd different cabs, speakers and two guitars. The best speaker to my ear for the 4-4-0 is a toss between a closeback G12h (nice thumpy bass) and the Blue (smooth and chimey). I will probably built a 2x12 cab mixing both speakers. SD JB pickups to me sounded good for the g12h keeping up the mids especially on solos and cut through the band and the speakers own bass response.

4x12 marshall blackbacks sounded good for that VH type sound but lacks lowend. A bigger OT will probably be a good idea.

This picture shows the two amps side by side. Notice those trany size differences. [link]

My friend who owns the express clone now wants to build the 4-4-0 after hearng it. I hope he won't be too busy and mail me the discs so i can post clips of both amps.

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views:

[kineteks]

I just got one of these kits and it's really nice. I'm a non-EEE/amp-guy & novice builder so I appreciate how complete the kit is and how good the online documentation is. Thanks Cliff...Brian too for generating the interest and keeping it going! I got the board loaded this weekend in very short order (I'm not allowed much time by the boss!) & expect the the whole project will come together quickly.

I did notice the 40u terminal error on the layout, as well as a couple of other minor things (I think?) R2 is labeled R1 & R37 is shown as R42. C21 & 15 are not shown as polarized caps. A super-minor point is a typo on the BOM showing R1a/R1b as Rfa&b, I'm a very literal guy...

So far on the build C1 is a little tight between the turrets and though there are a number of holes to choose from on the sweet CNC punched chassis, I couldn't find a set that matched the optional Heyboer tranny... so I drilled some more.
Not to be too lazy but if it already exists... the front panel hole spacing for a faceplate?

Now for my "dummy" questions:
large ga (18 ga?) twisted pairs... blk& wht are for the AC mains to the power switch? brwn/wht are for the filaments? .. the smaller ga (20 ga?) brwn/wht for filaments too?
the really small ga twisted or/yel & purp/wht are for C9/10 to V3 & R18/19 to the bias pots?
On my Ceriatone LP I just used 18 ga on the filaments and 20 ga on everything else!

Bias setting:
I have a couple of NOS 6SN7GTB, is there a common plate dissipation for this tube or is it unique for each mfg?
I'm going to need some help setting the bias, up to this point I've only dealt with cathode-bias amps....

[GainMaster]

Nice job on the board. I would have run the ground wire first though. You may want to put some insulation on one end of the tone stack caps as they pass under the ground wire. I usually use some of the teflon insulation stripped off the wire.

Brian

[kineteks]

...good point. I thought about it and figured I'd just insulate the ground bus with mini-shrink tube where it passed over the tone stack cap leads, is that a bad idea?

[GainMaster]

...good point. I thought about it and figured I'd just insulate the ground bus with mini-shrink tube where it passed over the tone stack cap leads, is that a bad idea?

No. I did the same thing on my first 4-4-0 build. Now the first thing I do is run the buss wire as it is easier to run a continuous wire before the rest of the components are wired. Also helps me remember where i am at on the board.

Brian

[cliffchappell]

I did notice the 40u terminal error on the layout,

I have fixed that on the latest plans.

as well as a couple of other minor things (I think?) R2 is labeled R1 & R37 is shown as R42. C21 & 15 are not shown as polarized caps.

Those were more corrections I made this weekend to the docs. They didn't show up in the posted pdf, so I probably built it with the wrong files.

I'll get it fixed and reposted.

A super-minor point is a typo on the BOM showing R1a/R1b as Rfa&b, I'm a very literal guy...

They look to be labeled Rfa and Rfb everywhere to me. That might just be a font issue.

So far on the build C1 is a little tight between the turrets

Right after you bought your kit, I had to build one for a customer and I made a couple of improvements to the circuit board. I made more room for C1 because it was tight, and I moved a couple of turrets where the space to be spanned by a resistor was almost too great (an example would be the 6SN7 grid resistors).

and though there are a number of holes to choose from on the sweet CNC punched chassis, I couldn't find a set that matched the optional Heyboer tranny... so I drilled some more.

I'll have to go and check again, but I don't remember having any problem using the holes that are there.

Not to be too lazy but if it already exists... the front panel hole spacing for a faceplate?

I can work something up for that.

Now for my "dummy" questions:
large ga (18 ga?) twisted pairs... blk& wht are for the AC mains to the power switch? brwn/wht are for the filaments? .. the smaller ga (20 ga?) brwn/wht for filaments too?

Filament wires are twisted brown and white. Use the 18ga. up to the 6SN7, and the 22ga from there on. I just always use heaver guage from the PT to the power tubes.

the really small ga twisted or/yel & purp/wht are for C9/10 to V3 & R18/19 to the bias pots?

Use one color twisted for the bias pots to R18/R19, and the other for the bias pots to R9/R12.

Bias setting:
I have a couple of NOS 6SN7GTB, is there a common plate dissipation for this tube or is it unique for each mfg?
I'm going to need some help setting the bias, up to this point I've only dealt with cathode-bias amps....[/quote]

I used 85% of PaMax in mine.

(0.85 * PaMax)/Va
(0.85 * 3.75)/342
3.1875/342
0.0093 or 9.3mA

[kineteks]

Cliff is this close?
2nd hole from the left was hand drilled(?) so it's not at round numbers. Hole sizes have been altered for the components I'm using...

[wrsrider]

Finished it up, I definately learned a few things about lead dress. There's some places I should've routed the wire differently, I may go back and fix it. I also have some tweaking to do on it, but I'm still really happy with the sound. 2W is loud as hell in a bedroom!

[kineteks]

Wreckless voltages:

B+1=351
2=325.3
3=286.1
4=264.5
5=249

V5 pin 1= 185.6
3= 1.67
6= 160
8= 1.31

V4 pin 1= 236.3
3= 2.59

V3 pin 1= 152
3= 43.4
6= 156.6
8= 43.4

V2 pin 2= 322.7
5= 323.5

Bias between TP 1&3=.0098 vdc TP 2&3= .0097 vdc

AC mains= 117
PT output= 278
Heater output= 6.86, after R1a&b= 6.43

Cathode voltages (43.4) on PI (V3) higher than projected values shown on the schematic (30.7), so showing 13.2 as opposed to the schematic’s 6.1 on lug 1 of the presence pot.

Full volume BUZZZZ! when either bright cap engaged & early onset of oscillation cured with grounding the shield of the wire from pin 2 onV5. Still more hiss than my Liverpool clone when the treble & presence are cranked up. I get oscillation with all the controls dimed, but just at the very end of the last pot’s travel.
No base on it yet & it’s just got the tubes that came with it installed, so there’s still stuff to do.
It’s definitely got some balls for a 2 watt amp! …maybe the optional Heyboer tranny contributes.
Great kit to build, can’t wait to get it tuned up….

[sst4270]

Just finished another one...

http://www.flickr.com/photos/32018625@N06/show/

These are great little amps.

Thanks again Cliff and Brian.

And yes, loud as hell, through a 2-12 in the basement. Not gig worthy, but perfect for studio or practice.

Enjoy,

Steve

[GainMaster]

Just finished another one...

http://www.flickr.com/photos/32018625@N06/show/

These are great little amps.

Thanks again Cliff and Brian.

And yes, loud as hell, through a 2-12 in the basement. Not gig worthy, but perfect for studio or practice.

Enjoy,

Steve

Man that is one fine cab. Did you build it yourself or have someone do it?

Brian

[Structo]

I'm not seeing where you can order this kit.
It see the page detailing the 440 but no kit.
Then when I click on the amps and kits to the left I see the PI and high octane amps but not the 440.
What am I doing wrong?