Since I'm working on a boat in a yard without power, I've splashed out
on a generator to power tools etc. It's from Machine Mart's cheaper
range - one of these: http://tinyurl.com/ya3f8za .

The generator works fine, but being a cheapish petrol one in an open
frame, it's quite noisy. I don't mind myself, but at weekends there can
be quite a few people working on their boats, and it feels rather
anti-social to be running a noisy generator when everyone else is
quietly cleaning and painting things in the sunshine.

Are there any cunning tricks to reduce the noise?

Cheers,

Pete

Pete Verdon wrote:
Since I'm working on a boat in a yard without power, I've splashed out
on a generator to power tools etc. It's from Machine Mart's cheaper
range - one of these: http://tinyurl.com/ya3f8za .

The generator works fine, but being a cheapish petrol one in an open
frame, it's quite noisy. I don't mind myself, but at weekends there can
be quite a few people working on their boats, and it feels rather
anti-social to be running a noisy generator when everyone else is
quietly cleaning and painting things in the sunshine.

Are there any cunning tricks to reduce the noise?

Cheers,

Pete
mass and padding round it.

"Pete Verdon" d wrote in
message ...
Since I'm working on a boat in a yard without power, I've splashed out on
a generator to power tools etc. It's from Machine Mart's cheaper range -
one of these: http://tinyurl.com/ya3f8za .

The generator works fine, but being a cheapish petrol one in an open
frame, it's quite noisy. I don't mind myself, but at weekends there can be
quite a few people working on their boats, and it feels rather anti-social
to be running a noisy generator when everyone else is quietly cleaning and
painting things in the sunshine.

Are there any cunning tricks to reduce the noise?

Cheers,

Pete

It was a very long time ago but I remember someone who had converted a
single decker bus to a mobile home. He had a generator underneath the floor
with a series of small exhaust boxes joined with U shaped pipe. As I
remember it was quite neat and quiet.

On 27 Jan, 22:58, Pete Verdon
d wrote:

Are there any cunning tricks to reduce the noise?

Turn it off when you're not using the angle grinder.

Swap it for a tenner's worth of 2kW building-site 4-stroke genny,
which is much quieter (and yes, a tenner )

Hide it inside or behind a baffle, which could be the boat you're
working on, oild drums etc. Just blocking the line-of-sight helps.

Do something drastic to the silencer, probably involving welding, such
that you can attach a length of flexible exhaust hose (you're a
boatyard, scrounge a knackered old bit off something). Route this into
a "pot" silencer, which is your local nearest equivalent to a cast
iron bucket (or chimney pot). Stuff a layer of loft insulation on top.

The Natural Philosopher wrote:

mass and padding round it.

I'm wary of just putting the whole thing in a duvet-covered box, as it
seems likely to overheat.

Pete

On Jan 27, 10:58*pm, Pete Verdon
d wrote:

Are there any cunning tricks to reduce the noise?

If you were to shut it in a box (like a 10ft ISO lined with
insulation), make sure it can breathe (and you or anyone else don't
die from CO poisoning).
Cunning? What about an audio rig that plays inverted sound waves which
cancel out some of the noise? The likes of Klark Teknik, Behringer,
etc no doubt have solutions to delay and phase the waves for optimum
effect.

Andy Dingley wrote:

Turn it off when you're not using the angle grinder.

I don't leave it running unnecessarily, but sometimes it's powering a
heater helping some epoxy or fibreglass to cure in the current weather.
This of course can look like I'm inconsiderately leaving it running for
no reason.

Swap it for a tenner's worth of 2kW building-site 4-stroke genny,
which is much quieter

This is a 2-ish KW 4-stroke genny, and I assumed it *was* the kind of
thing used on building sites.

(and yes, a tenner )

I'm intrigued. How?

Hide it inside or behind a baffle, which could be the boat you're
working on, oild drums etc. Just blocking the line-of-sight helps.

Last weekend I did put it among some of the less actively worked-upon
boats at the end of the yard, which helped a bit. But I don't want to
put it too close to someone else's boat - just after I'd packed it away
the owner of the boat I'd hid it behind/under turned up and started
taking off the covers - I'd thought the boat was basically abandoned.
There are also people living aboard at some pontoons just next to that end.

Do something drastic to the silencer, probably involving welding, such
that you can attach a length of flexible exhaust hose (you're a
boatyard, scrounge a knackered old bit off something).

This sounds promising. I haven't looked closely but I suspect the
exhaust (don't think it has a real silencer) is too thin for me to weld
to, but I could probably clamp something in place. One of my jobs is
replacing the knackered exhaust hose in my boat, but annoyingly I've
already thrown the old one away. I may have a short offcut from the new
one once it's fitted, but I'll probably want to use the genny quite a
bit before then. Nobody else seems to be doing engine work, but I wonder
if I can find some other kind of hose that won't melt.

Route this into
a "pot" silencer, which is your local nearest equivalent to a cast
iron bucket (or chimney pot). Stuff a layer of loft insulation on top.

Don't quite follow that. Just pipe into open-topped pot, with the top
blocked with glass wool?

Cheers,

Pete

Pete Verdon wrote:

Since I'm working on a boat in a yard without power, I've splashed out
on a generator to power tools etc. It's from Machine Mart's cheaper
range - one of these: http://tinyurl.com/ya3f8za .

The generator works fine, but being a cheapish petrol one in an open
frame, it's quite noisy. I don't mind myself, but at weekends there can
be quite a few people working on their boats, and it feels rather
anti-social to be running a noisy generator when everyone else is
quietly cleaning and painting things in the sunshine.

Are there any cunning tricks to reduce the noise?

Cheers,

Pete

connecting a bigger silencer onto the existing one can help enormously.
and they are free form any kwickfit type place, its nominally the pipe into a
silencer that fails first, so lots of usable*silencers end up in the*scrap
bin.**
\0

On 27 Jan, 23:28, Pete Verdon
d wrote:
Andy Dingley wrote:

Swap it for a tenner's worth of 2kW building-site 4-stroke genny,
which is much quieter *

This is a 2-ish KW 4-stroke genny, and I assumed it *was* the kind of
thing used on building sites.

Ah, I hadn't looked at your link. Yes, that's a lot better than one of
the Happy Shopper converted lawnmowers.



(and yes, a tenner )

I'm intrigued. How?

Plant sale the other week. Three of them went, no-one buying. usually
they'll raise £50 easily, these went to the same chap for a tenner
each. I'd have had one myself, except that I already have several and
no room for more tat.


This sounds promising. I haven't looked closely but I suspect the
exhaust (don't think it has a real silencer) is too thin for me to weld
to,

Can you get a spare bolt on flange, or any flange that matches the
studs & bore? Then abuse that, with Jubilees if necessary.

You need a few feet of flexi, which is hard or expensive to find, then
it's easy and you can use bits of old Ford escort, or whatever you
have. Most silencers have to be lightweight, which means noisy. If
yours is fixed, then you're laughing. Anything that combines path
length and an internal volume equal to ten or twenty times the
cylinder capacity works, so long as it doesn't turn into a drum
itself. A perfectly good silencer for a stationary engine can be made
from a labyrinth of stacked breezeblocks (the hollow sort), where it
uses mass and internal expansion volume to quieten the noise. There's
always a bit of high frequency left, so you stop that with a thin wad
of rockwool.

In message
,
Andy Dingley writes
On 27 Jan, 23:28, Pete Verdon
wrote:
Andy Dingley wrote:

Swap it for a tenner's worth of 2kW building-site 4-stroke genny,
which is much quieter *

This is a 2-ish KW 4-stroke genny, and I assumed it *was* the kind of
thing used on building sites.

Ah, I hadn't looked at your link. Yes, that's a lot better than one of
the Happy Shopper converted lawnmowers.



(and yes, a tenner )

I'm intrigued. How?

Plant sale the other week. Three of them went, no-one buying. usually
they'll raise £50 easily, these went to the same chap for a tenner
each. I'd have had one myself, except that I already have several and
no room for more tat.


This sounds promising. I haven't looked closely but I suspect the
exhaust (don't think it has a real silencer) is too thin for me to weld
to,

Can you get a spare bolt on flange, or any flange that matches the
studs & bore? Then abuse that, with Jubilees if necessary.

You need a few feet of flexi, which is hard or expensive to find,

How about PORTABLE STAINLESS EXHAUST . 1.5M LONG , 30MM WIDE


http://cgi.ebay.co.uk/PORTABLE-STAIN...-30MM-WIDE_W0Q
QitemZ370324020538QQcmdZViewItemQQptZUK_BOI_Indust rial_Tools_Generators_E
T?hash=item5639081d3a

http://tinyurl.com/yaw67qf

Ebay item 370324020538



then
it's easy and you can use bits of old Ford escort, or whatever you
have. Most silencers have to be lightweight, which means noisy. If
yours is fixed, then you're laughing. Anything that combines path
length and an internal volume equal to ten or twenty times the
cylinder capacity works, so long as it doesn't turn into a drum
itself. A perfectly good silencer for a stationary engine can be made
from a labyrinth of stacked breezeblocks (the hollow sort), where it
uses mass and internal expansion volume to quieten the noise. There's
always a bit of high frequency left, so you stop that with a thin wad
of rockwool.




--
Bill

Andy Dingley wrote:
On 27 Jan, 23:28, Pete Verdon wrote:
Andy Dingley wrote:

Swap it for a tenner's worth of 2kW building-site 4-stroke genny,
which is much quieter

This is a 2-ish KW 4-stroke genny, and I assumed it *was* the kind of
thing used on building sites.

Ah, I hadn't looked at your link. Yes, that's a lot better than one of
the Happy Shopper converted lawnmowers.

:-)

As I mentioned, one of its uses is to run a 2KW fan heater to warm up
internal spaces enough for fibreglassing. Can't see one of the little
2-stroke fart machines doing that.

Mind you, this 2-stroke claims the same noise level as the 4-stroke I
have: http://is.gd/7byM4

(and yes, a tenner )

I'm intrigued. How?

Plant sale the other week. Three of them went, no-one buying. usually
they'll raise £50 easily

Well, I'd gladly have paid £50 myself, but finding such a sale (even
knowing they exist) is a lot less convenient than popping over to
Machine Mart and being back in the boatyard 20 minutes later.

This sounds promising. I haven't looked closely but I suspect the
exhaust (don't think it has a real silencer) is too thin for me to weld

Can you get a spare bolt on flange, or any flange that matches

Doubt there's an official spare, and I haven't seen where the little
pipe actually attaches to. In the Machine Mart picture, the left-hand,
shiner, black box is the exhaust, presumably a crude silencer. The
actual outlet is the round hole in the middle, which if I remember
rightly has a small pipe inside it, ie not just an orifice in the sheet
steel.

studs & bore? Then abuse that, with Jubilees if necessary.

I was thinking in terms of either fitting a small-bore pipe around the
little pipe as it exits the black sheet-metal box, or if I could only
get wider boat flexi hose, wedge that against the box so that the
exhaust is firing down it but not actually sealed to it. Not fantastic.

You need a few feet of flexi, which is hard or expensive to find,

Why a few feet? Is this for gasses to cool down or something? Anyway,
I'm kicking myself for throwing away the perished old hose off the boat
- would have done for this job (as long as I could have sealed the input
end).

it's easy and you can use bits of old Ford escort, or whatever

How about I put a 90º bend in a length of 15mm central heating pipe,
wedge it into the genny exhaust (looks about the right size) and put the
bottom end in a bucket of water? Probably completely futile, right? :-)

Cheers,

Pete

On 27/01/2010 22:58, Pete Verdon wrote:
Since I'm working on a boat in a yard without power, I've splashed out
on a generator to power tools etc. It's from Machine Mart's cheaper
range - one of these: http://tinyurl.com/ya3f8za .

The generator works fine, but being a cheapish petrol one in an open
frame, it's quite noisy. I don't mind myself, but at weekends there can
be quite a few people working on their boats, and it feels rather
anti-social to be running a noisy generator when everyone else is
quietly cleaning and painting things in the sunshine.

Are there any cunning tricks to reduce the noise?

Cheers,

Pete

The usual solution (adopted by the water board who have to run pumps in
the street when there's a break in the mains) is to surround the
offending item with straw bales. Far enough away not to be a fire
hazard, of course.

On Jan 27, 9:42*pm, Dave Osborne wrote:
On 27/01/2010 22:58, Pete Verdon wrote:

Since I'm working on a boat in a yard without power, I've splashed out
on a generator to power tools etc. It's from Machine Mart's cheaper
range - one of these:http://tinyurl.com/ya3f8za.

The generator works fine, but being a cheapish petrol one in an open
frame, it's quite noisy. I don't mind myself, but at weekends there can
be quite a few people working on their boats, and it feels rather
anti-social to be running a noisy generator when everyone else is
quietly cleaning and painting things in the sunshine.

Are there any cunning tricks to reduce the noise?

Cheers,

Pete

The usual solution (adopted by the water board who have to run pumps in
the street when there's a break in the mains) is to surround the
offending item with straw bales. Far enough away not to be a fire
hazard, of course.

My uncle had a one-lunger from which he ran the exhaust into a hole in
the ground filled with clinker/stone etc. I don't think he had a
muffler/silencer on it all. Seem to remember a much quieter 'wuffling'
noise!

On Thu, 28 Jan 2010 00:14:12 +0000, Bill wrote:

You need a few feet of flexi, which is hard or expensive to find,

How about PORTABLE STAINLESS EXHAUST . 1.5M LONG , 30MM WIDE

http://cgi.ebay...

I was about to suggest eBay as a sourcec of various diameter flexable
exhaust pipe. I don't remember it being particularly expnesive
either.

Might be able to get a suitable silencer from the back of Quickfit or
similar.

--
Cheers
Dave.

Pete Verdon wrote:
The Natural Philosopher wrote:

mass and padding round it.

I'm wary of just putting the whole thing in a duvet-covered box, as it
seems likely to overheat.

A blockwork wall around it would probably be more effective anyway. Soft
materials stop high frequency noise. Heavy materials stop low frequency
noise, which can travel further.

Colin Bignell

Nightjar "cpb"@ insertmysurnamehere wrote:

A blockwork wall around it would probably be more effective anyway. Soft
materials stop high frequency noise. Heavy materials stop low frequency
noise, which can travel further.

OK - unfortunately it does need to remain somewhat portable, as I have
to drive to the boatyard each weekend with generator, tools and
materials in the back of my Polo. I could leave a certain amount of
low-value stuff (eg a few breeze blocks to construct a silencer) under
the boat, but a generator-sized blockwork compound, even dry-fitted, is
starting to take the ****.

Cheers,

Pete

On 28 Jan, 00:16, Pete Verdon
d wrote:


Well, I'd gladly have paid £50 myself, but finding such a sale (even
knowing they exist) is a lot less convenient

Farmer's Guardian.

Doubt there's an official spare,

Try unofficial? There are only so many combinations you can make with
two studs and a hole. It's often easier to connect to the block that
to the silencer outlet.


You need a few feet of flexi, which is hard or expensive to find,

Why a few feet?

Good static silencers are big hefty boxes. Your genny is on wheels.
You just need something to handle alignment and vibration.


How about I put a 90º bend in a length of 15mm central heating pipe,
wedge it into the genny exhaust (looks about the right size) and put the
bottom end in a bucket of water? Probably completely futile, right? :-)

That length of that diameter is going to be very restrictive,
especially once the exhaust has passed through one silencer and
expanded. It could reduce engine power, make it run over-rich, stop it
running altogether, and might even get noisier. The bucket of water
is good, but watch out for back siphoning when cooling down - you need
some good height between the engine and the water (you're in a
boatyard, there will be someone who knows water silencers).

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Pete Verdon
d saying something
like:

Are there any cunning tricks to reduce the noise?

Build a canopy with vent holes. Essentially that's what the industry
does, but you could molish one from ply lined with acoustic material.
Of course, a decent silencer is necessary.

"Pete Verdon" d wrote in
message ...
Since I'm working on a boat in a yard without power, I've splashed out on
a generator to power tools etc. It's from Machine Mart's cheaper range -
one of these: http://tinyurl.com/ya3f8za .

The generator works fine, but being a cheapish petrol one in an open
frame, it's quite noisy. I don't mind myself, but at weekends there can be
quite a few people working on their boats, and it feels rather anti-social
to be running a noisy generator when everyone else is quietly cleaning and
painting things in the sunshine.

Are there any cunning tricks to reduce the noise?

Cheers,

Pete


In my experience quietning the exhaust doesn't help much on many open-frame
generators, as a lot of the noise is mechanical from the engine and inlet
noise. An enclosure round it will help, but it's not very portable then.
As a quick test hold an old damp towel over the exhaust outlet while it's
running (only for a few seconds, before it chokes itself), to see how much
quieter it gets.
Althought it will cost you more, a better solution would be to sell the
generator you have, and buy one of the 'silent' enclosed digital generators.
I have a cheap 'Kipor' 3kw clone of one of the Honda models, and it is
*much* quieter than my open-frame honda-powered generator of the same output
power. Also the quality of the mains output from the digital one is
excellent, a decent sinewave, unlike a traditional generator.

Alan.

In article , AlanD
scribeth thus

"Pete Verdon" d wrote in
message ...
Since I'm working on a boat in a yard without power, I've splashed out on
a generator to power tools etc. It's from Machine Mart's cheaper range -
one of these: http://tinyurl.com/ya3f8za .

The generator works fine, but being a cheapish petrol one in an open
frame, it's quite noisy. I don't mind myself, but at weekends there can be
quite a few people working on their boats, and it feels rather anti-social
to be running a noisy generator when everyone else is quietly cleaning and
painting things in the sunshine.

Are there any cunning tricks to reduce the noise?

Cheers,

Pete


In my experience quietning the exhaust doesn't help much on many open-frame
generators, as a lot of the noise is mechanical from the engine and inlet
noise. An enclosure round it will help, but it's not very portable then.
As a quick test hold an old damp towel over the exhaust outlet while it's
running (only for a few seconds, before it chokes itself), to see how much
quieter it gets.
Althought it will cost you more, a better solution would be to sell the
generator you have, and buy one of the 'silent' enclosed digital generators.
I have a cheap 'Kipor' 3kw clone of one of the Honda models, and it is
*much* quieter than my open-frame honda-powered generator of the same output
power.


Also the quality of the mains output from the digital one is
excellent, a decent sinewave, unlike a traditional generator.


Unless I'm missing something how can the output from an alternator be
anything else or less than a sine wave?..

--
Tony Sayer

On 29/01/2010 17:43, tony sayer wrote:

Althought it will cost you more, a better solution would be to sell the
generator you have, and buy one of the 'silent' enclosed digital generators.
I have a cheap 'Kipor' 3kw clone of one of the Honda models, and it is
*much* quieter than my open-frame honda-powered generator of the same output
power.


Also the quality of the mains output from the digital one is
excellent, a decent sinewave, unlike a traditional generator.


Unless I'm missing something how can the output from an alternator be
anything else or less than a sine wave?..


Well, it's all a matter of scale. The 500MW alternators at your friendly
local power station do produce a very nice sine wave.

Coming down the scale, a 100kVA diesel genset provides a pretty good
sinewave (certainly nothing to sneer at for the vast majority of
applications).

Even smaller gensets down to 10 or 20 kVA will be OK if they have a
quality alternator and a reasonably resistive load.

However, when it comes to very small generators (of the order of 1kW),
the waveform is not so good. Rubbish alternators connected to
underpowered, poorly regulated engines with very little flywheels mean
that (among other things) the load regulation is poor, which leads to a
squiffy waveform. Also, the pureness of the sinewave from a small
alternator is dependant upon the characteristic of the load. If you put
a 500W halogen floodlight on your 750W generator, you would get a pretty
good sinewave. On the other hand, if you put a few compact fluorescents
and a few switched mode battery chargers and the portable TV set on your
750W genny (only pulling about 150W total), these things add up to being
a horrible non-linear load and the waveform would likely be all over the
place.

On 29 Jan, 17:43, tony sayer wrote:

Unless I'm missing something how can the output from an alternator be
anything else or less than a sine wave?..

Not enough cylinders to keep it rotating at constant speed, two
strokes in particular. This isn't a big problem though, as the
harmonic output of those is still pretty low. It's nothing like as
ugly a waveform as most inverters.

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Andy Dingley
saying something like:

Not enough cylinders to keep it rotating at constant speed, two
strokes in particular. This isn't a big problem though, as the
harmonic output of those is still pretty low. It's nothing like as
ugly a waveform as most inverters.

A cautionary tale:
Last year I had three one-day-long power outages and was running the
basics (TV, lights, UPS-PCs) from a cheapy Chinese inverter. Two months
after the first outage the TV gave up, and I got it fixed for ¤30
(East-West chip fault).
A couple of months after the second outage, the TV failed again, with a
psu fault - again, ¤30 repair.
I didn't connect the two at the time, but it became much more obvious
when the TV failed shortly after the third occasion, with the same fault
as the second time.

At the time it was a bit inconvenient, but it spurred me into biting the
bullet and buying something new rather than spend any more cash on an
elderly telly. Pity really, because it was a cracking set and I'd hoped
to keep it going for another year or two.

Sure as ****, I won't be running the new TV on a crappy inverter. I will
risk a laptop on a UPS, purely as a stopgap for the day.

In article , Dave Osborne
scribeth thus
On 29/01/2010 17:43, tony sayer wrote:

Althought it will cost you more, a better solution would be to sell the
generator you have, and buy one of the 'silent' enclosed digital generators.
I have a cheap 'Kipor' 3kw clone of one of the Honda models, and it is
*much* quieter than my open-frame honda-powered generator of the same output
power.


Also the quality of the mains output from the digital one is
excellent, a decent sinewave, unlike a traditional generator.


Unless I'm missing something how can the output from an alternator be
anything else or less than a sine wave?..


Well, it's all a matter of scale. The 500MW alternators at your friendly
local power station do produce a very nice sine wave.

Coming down the scale, a 100kVA diesel genset provides a pretty good
sinewave (certainly nothing to sneer at for the vast majority of
applications).

Even smaller gensets down to 10 or 20 kVA will be OK if they have a
quality alternator and a reasonably resistive load.

However, when it comes to very small generators (of the order of 1kW),
the waveform is not so good. Rubbish alternators connected to
underpowered, poorly regulated engines with very little flywheels mean
that (among other things) the load regulation is poor, which leads to a
squiffy waveform. Also, the pureness of the sinewave from a small
alternator is dependant upon the characteristic of the load. If you put
a 500W halogen floodlight on your 750W generator, you would get a pretty
good sinewave. On the other hand, if you put a few compact fluorescents
and a few switched mode battery chargers and the portable TV set on your
750W genny (only pulling about 150W total), these things add up to being
a horrible non-linear load and the waveform would likely be all over the
place.

OK point taken so if we have a rather light load on our Homebase 750
watt jobbie we may well get a half decent sine wave, but for the same
power genny can we assume that an inverter type will produce better
results..

Come to think of it the mains waveform round here, City area underground
cable fed substation 400 yards away isn't that much cop;!...
--
Tony Sayer

On 30/01/2010 22:44, tony sayer wrote:
In , Dave Osborne
scribeth thus
On 29/01/2010 17:43, tony sayer wrote:

Althought it will cost you more, a better solution would be to sell the
generator you have, and buy one of the 'silent' enclosed digital generators.
I have a cheap 'Kipor' 3kw clone of one of the Honda models, and it is
*much* quieter than my open-frame honda-powered generator of the same output
power.


Also the quality of the mains output from the digital one is
excellent, a decent sinewave, unlike a traditional generator.


Unless I'm missing something how can the output from an alternator be
anything else or less than a sine wave?..


Well, it's all a matter of scale. The 500MW alternators at your friendly
local power station do produce a very nice sine wave.

Coming down the scale, a 100kVA diesel genset provides a pretty good
sinewave (certainly nothing to sneer at for the vast majority of
applications).

Even smaller gensets down to 10 or 20 kVA will be OK if they have a
quality alternator and a reasonably resistive load.

However, when it comes to very small generators (of the order of 1kW),
the waveform is not so good. Rubbish alternators connected to
underpowered, poorly regulated engines with very little flywheels mean
that (among other things) the load regulation is poor, which leads to a
squiffy waveform. Also, the pureness of the sinewave from a small
alternator is dependant upon the characteristic of the load. If you put
a 500W halogen floodlight on your 750W generator, you would get a pretty
good sinewave. On the other hand, if you put a few compact fluorescents
and a few switched mode battery chargers and the portable TV set on your
750W genny (only pulling about 150W total), these things add up to being
a horrible non-linear load and the waveform would likely be all over the
place.

OK point taken so if we have a rather light load on our Homebase 750
watt jobbie we may well get a half decent sine wave, but for the same
power genny can we assume that an inverter type will produce better
results..

Come to think of it the mains waveform round here, City area underground
cable fed substation 400 yards away isn't that much cop;!...

I couldn't say Tony. I don't have any experience of using very small
gensets for anything other than powertools. Any gensets I get involved
with (for festivals) are usually in the order 60~125kVa 3-phase jobbies
and with these, I've never had a problem with incompatibility of
sensitive gear (including lighting control desks, video equipment,
general PC's, etc).

Mostly get problems with caterers (1) with sh*t installations popping
RCDs and (2) lying (or being clueless) about their max demand and
popping the laughably inadequate 16A supply they ordered on overcurrent.