Hot Rodding the Hot Rod Deluxe

[NTBluesGuitar]

All right, y'all...long-time lurker, first time poster comin' atcha...

I have an idea to build a PTP circuit that could replace the guts of an HRD. No...I'm not going to rip mine out as long as they're working, but when I recently did some maintenance on my HRD, the back of the PCB was charred in the area around the 5W power resistors. Not just the solder joints, but an area about the size of a 50-cent piece (I have a photo, but not online yet).

So I thought...if it were to ever die, or the PCB is damaged beyond repair, why not make use of the roomy chassis, good transformers, good tubes, and speaker and build a PTP circuit into it? My first thought was to get hold of an empty PCB and transfer/build he components into it, but Fender said they don't have any available. Fender was nice enough to have my local dealer refer me to another authorized dealer in Dallas, but they weren't keen on selling me one. And I quote, "I don't care what Fender told you, we're not allowed to release that part to the public." Fair enough, but when he started grilling me on what the problem was, it became a sales pitch for me to get them the amp to work on it.

I've read that the HRD is loosley based on the 5F6 (Bassman) circuit. Although, I think it resembles the 5F4 (Super-Amp) more...but they both have the same number and type of pre-amp/power-amp tubes. Sure there's no tube rectifier, but there IS room under the chassis for a hole to be punched for one. I can have it done here locally pretty easily enough.

I've seen that Torres Engineering sells a kit, but they weren't too helpful in answering my questions about it, and I've read reviews about some of their kits. Plus, the kit runs $300 which is almost what I paid for the amp. Sorry...but for only $75 I can get the circuit, tube sockets, wire and switches (including shipping).

The main question I have for y'all is: Would the HRD output transformer work with the 5F6 or 5F4 circuit? They're all originally (the Bassman re-issues upped the output I think) a 40W output, and it's really just a matter of speaker ohms then, right? There's plenty of room in the chassis for both circuits, although the Bassman circuit needs the filter caps outside the chassis for the sake of space.

Thanks in advance for your thoughts. I'm merely brainstorming ideas at this point. I have researched all the circuits and merchants who have all the parts, so it's a matter of compatibility of transformers at this point, I believe.

[Gris]

Get in touch with Justin Holton who discusses a rectifier and other mods on his site. Just google Justion Holton and Hot Rod.

[NTBluesGuitar]

Thanks for the suggestion. I am very familiar with his site, and, as a matter of fact, I was performing some maintenance and mods as suggested on his site when I discovered the charred area on the PCB. However, he's on a self-imposed hiatus from participating in things related to his site since it's his last semester of school and he's taking extra hours in order to graduate this year.

I've emailed him and haven't heard back yet.

However, if you know of any links or resources I may have not found yet that deal with power/output transformer compatibility, I'd be most appreciative to get them.

Thanks again.

[NTBluesGuitar]

As I previously mentioned, I have pics from the PCB burn I mentioned in my first post:



Anyway, this is why I am looking for a new, empty PCB for my HRD. Sorry for flooding my own thread...just wanted to get it all out there for a discussion.

[nitroburst]

Trust me ... Mine looks worse .:toobad I don't have any pics, But it's pretty bad. I'm thinking along the same lines as you. Next time the amp gives me grief The PCB is coming out for a P2P. I'm plotting which circuit will work the best. My main issue is I want to keep the verb. So I will have to add another tube & Choke. If you can find the specs for the HRD OT you could compair ohmage's. Good chance it would work? But I doubt the PT will work on a P2P board.

[JAM]

IMO, if you want a PTP amp, sell the HRD and get a kit (Weber or similar) rather than try to use the transformers etc with a new board.

[nitroburst]

IMO, if you want a PTP amp, sell the HRD and get a kit (Weber or similar) rather than try to use the transformers etc with a new board.

I understand what you mean,But the Weber kits have some cheesy componets IMO. I like my HRD as is, But if the PCB get any more crispy than it is now I won't be able to sell it with a clear consonance. So it will then become a good candidate for a P2P conversion at that point. For now... If it ain't broke don't fix it. :)

[NTBluesGuitar]

...the Weber kits have some cheesy componets IMO. I like my HRD as is, But if the PCB get any more crispy than it is now I won't be able to sell it ... it will then become a good candidate for a P2P conversion at that point. For now... If it ain't broke don't fix it.

My thoughts exactly. I, personally, have plans for an amp build from scratch (or from another existing cab, speaker, or parts), and like to order my own components rather than kits. I love Weber's kit designs, but it's a waste of money for me since I rarely leave things in their original state. That, and I get paid monthly, so I have to budget my projects and spread the cost out in stages.

I also don't think I'll be using a fiber board when I do my next build...it's not a sound thing, but a durability thing. Living in the South, things get kind kind of steamy here outside of the two monts of 'winter' we get. I'm going to go with a G10 epoxy board to avoid warping.

Anyway...with this thread, I was curious to see if anyone has done anything to a fried HRD involving a Fender clone PTP circuit. Heck, maybe I'll be the first...

[tdurik]

Herre's the schematic

http://blueguitar.org/schems.htm#Fender

Hopefully you can re-use most of the original components :)

[NTBluesGuitar]

Which schematic are you referring to? I have the HRD schems as well as the Fender PTP circuits I'm researching.

Maybe I'm looking in the wrong place?

[Kap'n]

But the Weber kits have some cheesy componets IMO. I like my HRD as is

Weber kits having cheesier components than a stock HRDx?




Sure, there are some components I change out when I build one. But compared to what's in a Hot Rod Deluxe? :toobad

[JAM]

Weber kits having cheesier components than a stock HRDx?




Sure, there are some components I change out when I build one. But compared to what's in a Hot Rod Deluxe? :toobad

Yeah, IMO the HRD IS a cheesy component!

[CraigJC]

But the Weber kits have some cheesy componets IMO

I've heard the same thing from Ron Hatcher, owner of Hatcher Amps. He's disappointed because he's had a long association with Weber, and loves Weber speakers in particular.

I suggest you check out Ron's kits. Nothing but the best components avaiiable. Ron builds top notch stuff.
Hatcher Amps and Kits

[NTBluesGuitar]

I'm familiar with Hatcher Amps! Great stuff! Isn't he an authorized Hoffman Board manufacturer? I dig Hoffman's stuff, too.

On a related note, I'm in the process of laying out a PTP circuit based off the HRDlx schematics so I don't have to worry about new PT/Choke/OT. I'm making good progress (with thanks to several good folks here for their advice), and hope to have it leave the drawing board in the next couple of weeks.

[robberry99]

Torres have released this new kit

http://www.torresengineering.com/nenewblboamp.html

Blackface style Boutique amp KIT
deville hotrod mod

Anybody know much about this or Torres and the quality and detail of their kits.

I have had enough of my HRDx amp, great sound WHEN it works but ever since the 5W resistors toasted my board I have had nothing but trouble with crackle. The footswitch pcb tracks lifted and the same with the inputs, one 6L6 socket had a bad joint and my preamp tube socket crackles when it vibrates. Its hopeless I have wasted so many hours tracking down bad connections, I have had enough and I want to do the ultimate mod, TRASH the PCB and have PTP. If anyone knows of any other replacement PTP kts for the HRDx besides Torres I would love to hear from you, thanks.

Rob

[Toneseeker]

That's a very old thread you revived there. TJ (NTBluesGuitar) has since replaced the inside of his HRD with a tweed 5e3 circuit. Yankee rob (based in Yorkshire) has done a 5F6A (tweed bassman) rebirth and I am currently working on a 5F6A build. Just waiting on the turret boards from Rob. I'll post on my progress soon but basically the chassis and ironware are very suited to 5F6A Conversion. Go for it. There's a lot of knowledge and experience on this site to make it easy.
Forget the kits. DIY.
Here's a pic of mine:

http://images.lilypix.com/displayima...bum=2259&pos=7

Pete

[robberry99]

Thanks Pete, I was wondering about a 5F6 conversion.

I am assuming that by using the schematic and layout diagrams one could construct the PTP board. Do the transformers, power & output, supply the correct values to use? I have a little experience but not the technical knowhow to configure correct power supplys if the voltages are different.

[Toneseeker]

There are several ways you can construct the circuit boards but the best way is to use a material called Garolite G10. Unfortunately as far as I know it's only available in the USA and you may have to buy it in bulk. The board is drilled and small metal pins called turrets are installed. Again UK supply is almost zero. The best ones are Harwin Turrets, USA again. The layout can be bespoke or standard Hofmann style. You can buy either a bare turret board or a populated one from any number of websites and maybe some of the guys on this site can point you in the right direction of board suppliers. I'll speak to Rob and see if he is interested in supplying your boards.
The HRDx voltages are pretty close to what's required by the 5F6A but ther's a few little circuit tweaks required to the bias circuit etc. The feedback resistors need changing to match the output transformer but we have the pitfalls well covered. If you have a Hot Rod Deville it's a little more tricky as the voltages are a tad higher but again, we've got that covered. There are a few other things to consider like wheteher you will use a Full wave bridge rectifier or a copper cap. I've gone down the copper cap path.
If all this is a bit daunting don't worry there are a lot of guys here willing to hold your hand, at least 3 of us in the UK.

Pete

[robberry99]

Thanks again Pete, if your friend can help with a turret board I am interested, otherwise I could order one from the US from here
http://www.hatcheramps.com/products.asp?id=17

Is there much of a savings in just getting the board and buying the components here in the UK?

[Toneseeker]

Yikes!! $200 for a loaded board? That's about £100. I think you can do it a lot cheaper. However it's the choice of components etc that you will have no control over. Remember this is a HRDx conversion so it's not 100% 5F6A. I am using higher wattage carbon film resistors etc to build in reliability. I'm not sure whether that circuit board material is actually Garolite. I wanted to have an effects loop cause the 5F6A doesn't have one so I'm a bit non-standard there. My conversion will have 3 small boards as opposed to the 1 board Hofmann type solution. Besides you'll get a lot more satisfaction out of choosing your own components. There are tonal differences in the choice of capacitors etc. We can recommend the right suppliers, mostly uk. I do have a drilling template for the Hofmann board if you want to go down that route but lets see what Rob say's. Feel free to email me direct if you want to.


Pete

[robberry99]

I thought it was a bit pricey, but I guess that would include telephone support and warranty.

Your right, part of the fun is the choosing of parts, I have sent an email so if you and Rob have any info I would be eternally gratefull. I am down in the deep south of the UK in Southampton, we have an RS and Maplin nearby so components are easy to get.

[NTBluesGuitar]

OLD THREAD ALERT! Man, have I learned a lot since this posted first.

That's a very old thread you revived there. TJ (NTBluesGuitar) has since replaced the inside of his HRD with a tweed 5e3 circuit. Yankee rob (based in Yorkshire) has done a 5F6A (tweed bassman) rebirth and I am currently working on a 5F6A build.

Thanks for the nod, Pete. Actually, I'd put in the 5E5A Tweed Pro in these. It's the closest match to tube complement, wattage, and voltages.



The rebuilds we TFF'ers have done so far re-uses all the HRD hardware, from transformers to pilot light. That's what's fun about these projects, IMO.

I have yet to hear anything postive about Torres's work, especially considering what he charges.

[Toneseeker]

Hey TJ, I never tire of looking at that picture. Nice neat job. Mine is further along now. I rewired the heater supplies 3 times and it still looks a mess.

Pete

[robberry99]

Wow, thats a really nice job, any chance of a hi res image? I see you are using the eminence patriot, how do you find it?

[NTBluesGuitar]

The Eminences are outstanding! They're my new favorites.

Texas Heats are what I'd go with for a stock HRD, but the Red, White & Blues does the tweed thing nicely.

E-mail me and I'll get you links to more pics!

[yankeerob]

Hey Robberry,

I've already successfully built a HRDv/5F6A conversion (with the expert help from a few of the chaps here) and am about to make some turret boards for Pete (TS) for his HRDx/5F6A - I now just crank it and play - I never worry if it's gonna hold up because I built it from quality parts - it's the same Garolite G10/FR4 board that TJ uses (only in a light green - it comes in many colours but is only available in light green from my UK supplier) - Harwin turrets - Vishay Roederstein caps (similar to Mallory 150's) - this is what my HRDv looks like inside now



You can see an extra space for another preamp tube at the far right - when we get the send/return circuit perfected a 12AT7/ECC81 will go there as part of it.

As for the sound - it's everything I wanted and more - its pretty clean all the way up to flat out but has serious tone - and I don't miss the reverb because it sounds that good I couldn't care less... I use a Black Star HT Dual DS-2 for dirt and boost - I've used it on quite a few gigs now and always get asked how I get 'that rhythm sound' - the answer is I couldn't afford to buy an amp that sounds like it so I built one out of what I had... if you're really interested in doing a build and need some boards making let me know via email...

[robberry99]

Thanks Rob

I was curious about what was the best way to get dirt and boost, my problem with the HRDx has always been the midrangey honky sound and the lack of low note definition of the drive channel. Does the Black star keep the bandwith and clarity? Of course nothing beats power tube breakup, have any of you looked at the power scaling methods.

I have tried yellow jackets with EL84s, that works nice but makes it sound like an AC30 cranked.

[yankeerob]

Hmm - there's a lot there to comment on - the midrangey honky sound is more to do with the speaker - the standard 'Fender Special Design' Eminence is just that - midrangey and honky - the cure for me in that area was Celestion G12-100T's (Hot 100's) - they're cheap in the UK - if you have problems sourcing them here gis a shout - they're fairly sensitive, reasonable flat response and have a resonant freq of 86 Hz...

The Black Star is virtually transparent if you want it to be or can colour the sound - it runs a 12AX7/ECC83 at 300V so it's not like many valve driven distortion pedals that run the valve under voltage and sound soft to my ears - you can use it for clean boost or crunch on channel 1 and straight dirt on channel 2 - the bypass is excellent and I don't experience any real loss on a coupla 10 metre cables but doesn't sound active either... it also has a funky tone stack adjustment called 'ISP' - as far as I can make out it shifts the mid around - I use mine full over to the 'American' setting...

Forget any of this 'power scaling' malarky - I have never looked back since getting my 5F6A going as a straight vintage design amplifier - I struggled a bit marrying some of voltage/impedance differences between the original circuit design and the HRDv power supply/bias feed and then the OT/global feedback etc but we got there with the help of some of the guys here... once you hear and use your HRDx with a vintage style front end you won't look back - they sound so good and solid it just makes you angry that Fender don't make 'em like this any more... and that you spent so much on a what is essentially a pile of dung...

Yellowjackets will always do that - I've spouted endlessly about this 'AC30' sound thing - it's more accurately put a 'EL84' thing - I've owned a good handful of EL84 amps (Peavey Classic 30's, Laney LC15, TT20 head etc...) and they sound like what they are - amps running EL84's - it just so happens that AC30's use them too and is probably the most famous amp that does - but you'll never get the rich, deep warmth of 6L6's out of em... especially on you bottom E - that's where it really shows

[yankeerob]

I've got a pressie for Pete...

[NTBluesGuitar]

It doesn't count unless it's done on one piece.

[yankeerob]

It doesn't count unless it's done on one piece.

Didn't know there were rules

It's a case of accomodating both HRDx and HRDv transformer sets - rather than make one board for all (and wasting board and turrets) it's just more practical to make a PS board for either and a front end board for both - I like the 4 x 47uF approach (in parallel and then series) on the first filter stage with Dv iron and was also concerned about space as I hadn't got definite dims and locations for the through chassis PT on a Dx... plus I knew Pete wants to try and get the S/R board in there as well - so yet again we'll be attempting to break new ground with that... I've re-jigged it a bit; made it simpler to mod if necessary and changed the earthing scheme so all the earths are star wired and anchored near the treble pot apart from it's own filter cap (which I'm not sure is entirely necessary) which goes back to the PS... putting the S/R jacks in their former position is a no no as well - and I suspect they'll have to be isolated from the chassis - with this thing being where it is in the circuit - I'm trying to leave no stones unturned...

I'm sure the rest will be a doddle - a little tweak here and there with the global feedback resistors and maybe the slope resistor but apart from that it's stuff we know - I'll email you the layout - I guestimated the location of the PT but apart from that it's as close as I can get it at present... wish I could get a decent price on export iron for these - it's not bad though I've heard of more Dx OT's going home than Dv's - even the 410 idiot who tipped up with his bias pot wound full up got away with only needing a coupla bottles - BTW - I've acquired a Peavey Encore 65 export PT for salvage - made by Basler - sounds favorite for the O-Clone - just gotta find a 60W OT - will probably source a 041754... will start a thread when I'm ready to build something to accomodate a coupla KT66's - anyway - gotta go post Pete's stuff!

[NTBluesGuitar]

Didn't know there were rules

I make them up as I go.