NPAD: GSS Sumo 1000

[Hellzero]

Will be, the GSS Sumo is a terrific dead silent power amp. The only slight "issues" being the input at the front and the switch at the back... But these are details, especially after you've plugged it.

[bassmayhem]

On 18/10/2020 at 22:29, bassmayhem said:

An old thread, but interesting...
I just found a second hand Sumo to use with my Jule Amps Monique and the new Genzler cabs arriving this week. The Monique dove cage into Sumo into BA 210-3 SLT and BA 15-3 SLT. Should be neat and devastating...  

I tried the Sumo 1000 a couple of times now, but I am not fully satisfied...
I found the volume level kind of low with the Monique in front, compared to using my Genzler Magellan 350. I have to do some more testing before I make my decision.

Edited November 7, 2020 by bassmayhem

[chyc]

3 hours ago, bassmayhem said:

I tried the Sumo 1000 a couple of times now, but I am not fully satisfied...
I found the volume level kind of low with the Monique in front, compared to using my Genzler Magellan 350. I have to do some more testing befor I make my decision.

One thing I've found with my GSS amp is that the gain pot is linear. It's actually a nasty trick that other amp manufacturers use to make their kit seem louder. I'll just copy-paste what Gollihur has written on the EA iAMP classic, which also uses a linear volume control:

Quote

Rather than have all the volume in the first turn of the knob, EA uses potentiometers that are more linear. This means you may actually have to turn the master volume all the way up to the 3 o'clock position when things get really, really loud. This gives you a more realistic measure of how much power you are using. Most other amp manufacturers (and think stereos, car radios, etc.) use a taper that puts all the volume up front. This is to impress unsuspecting customers trying gear in stores. "Wow, listen to how loud it is, and it's only on 2? ," he says, and thinks to himself, ”This thing must get really loud!!”

Like you I was unimpressed with the loudness of my GSS amp head when I first received it, but I think that was my expectation of volume controls rather than the amp itself. I should say it wasn't the Sumo so take your own experience over my anecdote.

[bassmayhem]

2 hours ago, chyc said:

One thing I've found with my GSS amp is that the gain pot is linear. It's actually a nasty trick that other amp manufacturers use to make their kit seem louder. I'll just copy-paste what Gollihur has written on the EA iAMP classic, which also uses a linear volume control:

Like you I was unimpressed with the loudness of my GSS amp head when I first received it, but I think that was my expectation of volume controls rather than the amp itself. I should say it wasn't the Sumo so take your own experience over my anecdote.

Exactly! Unlike other amps, you have to turn the knob very much before things start to happen. Maybe just that...  

[bassmayhem]

Nope! I sent it back. Not convincing at all.

[MOSCOWBASS]

I've just received a sumo 600. I run a Mesa d800+ pre into it. Only house use so far, but seems plenty loud. I usually feed the Mesa d800+ pre into my Mesa d800. The sumo is a backup, but nice for house use as no fan noise. I run two 4 ohm cabs when required (very few gigs), so the Mesa d800@2ohms is fine for that. Most gigs are just one cab, so the Sumo covers these. Impressed so far.😂

[BassmanPaul]

On 23/02/2018 at 05:41, HazBeen said:

 Like most D Class amps I doubt the Sumo gives the full 1000w all the time,

There isn't an amp made that outputs it's full power all the time. They only do that when the input signal is strong enough to drive them that far. 

[HazBeen]

13 hours ago, BassmanPaul said:

There isn't an amp made that outputs it's full power all the time. They only do that when the input signal is strong enough to drive them that far. 

It only took 2.5 years for anyone to notice my comment was ambiguous. We agree and it is not limited to only D class.

[Passinwind]

On 22/10/2020 at 03:55, chyc said:

One thing I've found with my GSS amp is that the gain pot is linear. It's actually a nasty trick that other amp manufacturers use to make their kit seem louder. I'll just copy-paste what Gollihur has written on the EA iAMP classic, which also uses a linear volume control:

 

That linked text is confusing at best IMO. In the more basic circuit applications a log taper pot typically gives that more linear sounding result. 😎

And there's maybe really nothing all that inherently nasty about using a less expensive part that behaves in a way many people prefer, eh?

[chyc]

6 minutes ago, Passinwind said:

And there's maybe really nothing all that inherently nasty about using a less expensive part that behaves in a way many people prefer, eh?

Nothing wrong with it if you prefer it, but I'm not one of them. It annoys me when volume controls make no difference to my ears past the halfway mark. This is more pronounced on my TV and Hifi than anything else. No log taper pots in those, just cynical marketing (IMHO).

[Passinwind]

50 minutes ago, chyc said:

Nothing wrong with it if you prefer it, but I'm not one of them. It annoys me when volume controls make no difference to my ears past the halfway mark. This is more pronounced on my TV and Hifi than anything else. No log taper pots in those, just cynical marketing (IMHO).

Roger that, and it certainly can work as a marketing ploy, probably especially with consumer widgets. It annoys me when the amp doesn't get to giggable level until two o'clock too though. On pieces I build for myself I try for a sweet spot in control sweep from about 10 o'clock to 2 o'clock when possible. Not just for volume controls, but everything else as well.