Point to point vs pcb (probably yet again)

EdGrip

Yeah, when people say PTP they usually mean eyelet- or turret-board. PTP is just a recipe for needless mess.

Richardj

Guilty as charged!  I (obviously wrongly) consider amps that are not PCB in that vein as they have the components more or less directly connected rather than soldered onto the tracks of a PCB.  My bad, but it is to the lay person a similar concept.

ICBM

The lay person would be wrong. They are no more directly connected if they're soldered to a turret or an eyelet which is joined under the board to another turret or eyelet by a wire - in fact, *less* so than on a PCB since there are actually more solder joints. (Component > trace > component on a PCB, component > turret > wire > turret > component on a turret board.) So actually PCB is closer to true point-to-point from that reasoning. No that it matters... as long as the joints are correctly soldered it makes no difference how many there are.

Dave_Mc

You'll get better (read: funnier) answers if you post this on TGP. >:D<

Seriously, though, I dunno. As ICBM says, it's virtually impossible to try the exact same thing where the only difference is whether it's PTP (more likely turretboard) or PCB. I've never tried an amp I liked (or didn't like) where I could point to its being PTP (or PCB) as being the only reason why it was good (or bad). That's good enough for me.

JohnPerry

ICBM said:

JohnPerry said:

I'm not sure of the technical specifics of it. But i've gone through a hell of a lot of amps over the years and the hand-wired jobs i have now are incomparably nicer sounding that the PCB amps i've had. The real night-and-day comparison was when i sold a vibroverb reissue and bought a silverface PR. The PR was twice the amp really. The vibroverb was fine (and good enough for Jeff Buckley, let's face it) but it didn't have the clarity or richness of the old PR. There may be other factors in play but the most obvious was the way it was wired, i'd have thought

So not the different circuit, different speakers, different transformers, different caps, different resistors or different valve types, then?

the tubes and the speakers were the same, in fact, but i take your point

ICBM

JohnPerry said:

the tubes and the speakers were the same, in fact, but i take your point

6L6s in the Princeton or 6V6s in the Vibroverb?

Just curious... neither is really ideal.

JohnPerry

Just meant the quality of tubes were the same. JJs in the power stage and old Mullards in the pre-amp. But it was more that the Princeton sounded way more alive and, well, Fender-sounding. The Vibroverb was like a simulation of an old Fender by comparison. I grant you the wiring is probably only part of it

menamestom

I really like those Vibroverb reissues, a mate has one and it sounds glorious, but it needs to be cranked. It remains pretty clean but comes alive at volume. I have a PR reissue, sounds great at lower volumes but gets a bit ratty loud. Apples to oranges really.

menamestom

So not the different circuit, different speakers, different transformers, different caps, different resistors or different valve types, then?

Although different circuit probably covers it I've read the short tailed PI separates the PR from the bigger fenders as well. When I got my PRRI i read quite a bit about mods and some people upgraded the transformers, changed to 12" speakers and had the amps converted to long tailed Phase inverters so they sounded like 'mini deluxe reverbs'. Why they didn't just buy DRRI I don't know but there you go....

ICBM

JohnPerry said:

Just meant the quality of tubes were the same. JJs in the power stage and old Mullards in the pre-amp. But it was more that the Princeton sounded way more alive and, well, Fender-sounding. The Vibroverb was like a simulation of an old Fender by comparison. I grant you the wiring is probably only part of it

While I would be the first to say the type of power valves makes less difference than usually thought, there's still a difference between 6V6s and 6L6s.

Were the speakers identical, or just both 10"?

This is not to mention the circuit or the cumulative differences in all the component types...

It's very easy to look inside an amp and see an eyelet board or a PCB, and think it matters - but trust me, if it does it's way, way down on the list behind everything else mentioned here.

JohnPerry

ICBM said:

JohnPerry said:

Just meant the quality of tubes were the same. JJs in the power stage and old Mullards in the pre-amp. But it was more that the Princeton sounded way more alive and, well, Fender-sounding. The Vibroverb was like a simulation of an old Fender by comparison. I grant you the wiring is probably only part of it

While I would be the first to say the type of power valves makes less difference than usually thought, there's still a difference between 6V6s and 6L6s.

Were the speakers identical, or just both 10"?

This is not to mention the circuit or the cumulative differences in all the component types...

It's very easy to look inside an amp and see an eyelet board or a PCB, and think it matters - but trust me, if it does it's way, way down on the list behind everything else mentioned here.

i burgled the vibroverb for the best tubes and an eminence (ragin cajun IIRC) and stuck them in the princeton.

Sessionman

Hi Guys,

As you will see, I'm new on FB and was inspired to sign up after reading this thread.  I'm not really a 'forum' person and don't have a lot of time.  But after so many years in the guitar amp business and verbally fighting off 'forum fantasy' beliefs about technology, it's nice to see so much informed 'real world' chat going on here.  Seems like a lot of you have an electronics background, so I might be, at last, in good company. 

I am a formally trained electronic bod who has spent much of my career designing guitar amps made with transistors and PCBs (valve background though)... so you can probably guess I've had a pretty hard time!  Heard every negative comment that's possible!  Lol.

So, that's about it.  Hope to make the odd contribution when I feel motivated to do so.

p90fool

Sessionman said:

Hi Guys,

As you will see, I'm new on FB and was inspired to sign up after reading this thread.  I'm not really a 'forum' person and don't have a lot of time.  But after so many years in the guitar amp business and verbally fighting off 'forum fantasy' beliefs about technology, it's nice to see so much informed 'real world' chat going on here.  Seems like a lot of you have an electronics background, so I might be, at last, in good company. 

I am a formally trained electronic bod who has spent much of my career designing guitar amps made with transistors and PCBs (valve background though)... so you can probably guess I've had a pretty hard time!  Heard every negative comment that's possible!  Lol.

So, that's about it.  Hope to make the odd contribution when I feel motivated to do so.

Cool, welcome aboard! There aren't too many technology snobs around here, your perspective will be viewed with interest.

JayGee

GuyBoden said:

My problem is that I can't see the components on a PCB board, they're too small, but I can see them on a Point to Point board, it's probably age related.

There's absolutely no reason why you can't use exactly the same components on a PCB as you'd traditionally find in a tag/turret board (or true P2P for that matter) build and in fact if you look at early PCB amps that's pretty much what you'll see....

Sessionman

There's absolutely no reason why you cannot substitute the turret board with a PCB to the same layout... I've done it back in the 1970's!  And use the identical components.

ThePrettyDamned

The reason some (though not all, and perhaps not even most) handwired kit sounds better is because of careful lead dress, layout (all of which can be done on pcb anyway) and component selection. Also, they are generally simple circuits. Actually, most independent type amps I've seen are tweed or vintage Marshall, you don't get many high gainers or new sounds (there are some, I know sabre have some interesting stuff).

Pcb amps are made for production. Actually, I'd be interested to know how many hand wired folks would benefit from a pcb build - they're cheap enough, and if it was split into 2 or 3 key parts, fixes would be easier - just swap the board. But then, it might be easier to repair a turret board amp still (point to point just looks like a bloody mess!).

But production amps don't necessarily use top quality components, instead going for the cheapest. Spending a few more pence on some caps is no big deal to an independent builder but to a company churning out hundreds, it adds up. And that's less profit.

Richardj

I started this discussion because someone essentially rubbished my Cornford Roadhouse 30 on the basis that it was far eastern junk (yeah!) compared to the Hurricane, Carreras etc because they were truer handwired and simply 'better' full stop.  Not saying they aren't great, but are they better simply because the Roadhouse series were PCB?

JayGee

ThePrettyDamned said:

The reason some (though not all, and perhaps not even most) handwired kit sounds better is because of careful lead dress, layout (all of which can be done on pcb anyway) and component selection.

Actually I think a lot of it is down to a combination of not selling into the  cheaper  end of the market (and hence not building/designing down to a price), needing to differentiate the product from the cheaper stuff, and plain old fashioned pride in workmanship and giving a damn...

Or, to put it another way, hand wired stuff tends to sound better because it's built/designed/engineered by people who both want and need to build stuff which sounds better and who have the luxury of selling to people who are willing to pay a little more for something which sounds a little better.

Another thing to bear in mind is that PCB production "front loads" the cost because you need to pay up front for the design and artwork, possibly (probably?) going through a number of iterations along the way - I know that CAD/CAE/CAM has pushed some of those costs down quite a bit from the old days of literally "taping out" a board design, doing the photolithography thang, and dipping boards into ferric chloride but even so, if you're only building a relative handful of amps then it may simply not be cost effective to go PCB and a cleverly laid out turret board which you can build multiple designs on may be the best option financially!

ecc83

jpfamps said:

ecc83 said:

And when you start to get into very high gains P2P makes stability/hum issues tricky. More or less a de-bugging exercise for every individual chassis.

Turret tag is better but once you have a PCB sorted, its sorted!

Dave.

We've built several high gain amps with channel switching using turret board with absolutely no stability/hum issues, and no need for debugging.

Equally there are PCB amps with known stability issues (eg the Blues Junior).

Yes, I agree electronics can serve you problems no matter the construction.

Perhaps I was put off P2P very early on having to fault find a PAL I decoder built in that way! (ITT-KB hybrid CTV) . We are talking seriously deranged spider here!

Dave.