• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Ampeg SVT-7 Pro TEST

#122
I am no tech,so I am not sure if I am clear on what I have been reading. this is my take

BGM did some tests with a normal power supply, like most of us will be using ( but they made sure there was no fluctuation) and it came out 250 odd watts less then the specs specify.
Someone else tested the amp but bipassed the preamp . No one is going to by that amp to use as a power amp, and it still came up short. close, but short.
The ex ampeg tech said
I have no problem with measuring an amp with an unregulated line that may drop to whatever voltage..... But I DO have a very serious issue with taking the results as being "meaningful" in terms of the measured power vs manufacturer's claims . THEY ARE NOT.
Click to expand...

Tom from BGM said
Again, almost no bass player is going to gig out with regulated AC, so we don't test with regulated AC. But we do test with good power, and we monitor voltage during the testing, so if there is any voltage fluctuation from an external condition - like line voltage at the wall dropping on its own - we retest
Click to expand...

It still seem to me that they a lying on the specs. Maybe you can get 1k watts out of it on a regulated line, But most bass players will not have that option...

I am looking forward to the new test results.

nutdog said:
...
Now that an Ampeg product doesn't match the advertised specs in the BGM test, the testing method is now under suspicion by some of the very people that touted the BGM micro VR test results as proof of Ampeg honesty.

The input from an ex-Ampeg engineer is interesting. The TBer test of the amp section is interesting.

But in the TC thread everyone wanted and expected an explanation from TC. I've seen Ampeg post on TB before. There is no reason not to expect Ampeg to provide an explanation. It may very well be all legit and reasonable. So they can clear it up.

But if they don't, it will never be completely clear.
Click to expand...
I find this funny. Not ha ha funny. The Ampeg fanbois seem to be reading what they want to read.
 
#123
vin*tone said:
DO you have a variac? I'd be interested to see how input voltage influences power output. ie. It would be good try and replicate bothe the BGM and Ampeg results to gain an understanding of why there is such a discrepancy.
Click to expand...

Keep in mind that a variac does not necessarily regulate power, and using one does come at some cost, most notably a change in the line impedance of the AC source.
 
#124
Mod Insert:

After finding this, and reading 7 new pages of discussion on this, I'd like to say thanks to those of you who are participating in some great tech.

I'd also like to issue a warning, and I'm only doing it once this time, unlike the 5 times I asked you all last time:
There has already been some sort of posting that led to the closure of the previous thread.

Keep that up, and I'll be none-to-happy to waltz right back in here and start handing out tickets again.
Quoting that junk is just as bad as writing it, so, if things are getting touchy in here, please use the report post button instead of engaging in all the junky-junk that ended so badly last time.

Again: cheers on some really great discussion here!
 
#125
Thanks for keeping it open. Third party tests of amp performance are something that many of us were begging for when I joined TB, and now that it's a reality, I think it's valuable to have an open dialogue about the nature of those tests.
 
#126
fdeck said:
Thanks for keeping it open. Third party tests of amp performance are something that many of us were begging for when I joined TB, and now that it's a reality, I think it's valuable to have an open dialogue about the nature of those tests.
Click to expand...
I'm loving every minute of it. I wish we could gamble on it ;)

So Tom Bowlus just said in another thread that they benched an SVT 8 Pro, and it performed up to its specs. Just sayin...
 
#131
JimmyM said:
I'm loving every minute of it. I wish we could gamble on it ;)

So Tom Bowlus just said in another thread that they benched an SVT 8 Pro, and it performed up to its specs. Just sayin...
Click to expand...

Nice! I'm not familiar with the 8 Pro, I read on Ampeg web that it is a 2500W amp, and that the power amp is solid state. Not class D?
So it is more like the Markbass II and III regarding the poweramp technology?
 
#132
I'm not sure which class it is but I'm almost positive it uses an SMPS and not an iron power transformer. It would have to if it weighs 23 lbs. The Micro VR is class AB, which the LMII and III are, too. Bwyond that, don't know much about it, and wouldn't know what to do with it if I had it. Big wattage amps scare me.
 
#134
In an effort to give the amp the benefit of the doubt, I took my gear to my friend's house. As a bonus, his power tested at 118v, so somewhat better than mine. I assumed an active bass, and went with 2v as maximum allowable input. I maintained a steady input signal of .5v at 1 kHz while twiddling knobs until maximized output. I then ran the test into an 8ohm dummy load, I calculated (v*v/ohm) (70v*70v/8ohm) 612.5 watts. Into a 4ohm dummy load, I got (62v*62v/4ohm) 961 watts.

In my (limited) experience, I'd have to call the amp legit. The tone is amazing, and there's something to be said about being able to rackmount. I may have to think about picking one up for myself. Nah, I still like my Streamliner better.
 
#135
Duke21 said:
Nice! I'm not familiar with the 8 Pro, I read on Ampeg web that it is a 2500W amp, and that the power amp is solid state. Not class D?
So it is more like the Markbass II and III regarding the poweramp technology?
Click to expand...

Nope, the SVT-8Pro is a class-D amp.
 
#136
In case I haven't said it before: I am not an engineer, I just like to play with toys (amateur radio, SCUBA, sound reinforcement, stereo, etc). I have good test equipment, and know pretty well how to operate it. However, nothing I get should be used to disprove anyone else's results. All my tests prove are that I was able to get one specific unit to achieve these numbers on one specific day. I make no other claims about the gear. Okay, one other... I love the tone and the look of the SVT-7 Pro. It is certainly possible that I made a mistake somewhere, even. I don't think I did, but can't discount the possibility - just trying to be fair and unbiased here.

Again, I don't own any Ampeg gear, and am not an endorser.
 
#137
Mod Insert:
This is a public warning.
Anyone who wants to chase this topic from thread to thread looking for/creating/reacting to personal slurs, insults, fist fights...I'm done asking you all to treat each other nicely, and use the report button.
Any more instances of this that I see are going to be treated as repeat violations, which double infraction points which can, and will lead to an auto generated ban of one duration or another if you have a ledgerbook full of past infractions.

There is *absolutely no reason* why any of this, past, present or future, this amp or that amp, needs to be personalized/agenda-sized, and from now on, the TalkBass Amps Section will be a more friendly place to discuss things.

Got it?

Carry on, and, many, many thanks to those of you who have brought great tech and civil discussion to this thread. I've learned a lot, and this thread/topic can actually be a good example of what's good here at TalkBass.
 
#139
tekdiver500ft said:
In an effort to give the amp the benefit of the doubt, I took my gear to my friend's house. As a bonus, his power tested at 118v, so somewhat better than mine. I assumed an active bass, and went with 2v as maximum allowable input. I maintained a steady input signal of .5v at 1 kHz while twiddling knobs until maximized output. I then ran the test into an 8ohm dummy load, I calculated (v*v/ohm) (70v*70v/8ohm) 612.5 watts. Into a 4ohm dummy load, I got (62v*62v/4ohm) 961 watts.

In my (limited) experience, I'd have to call the amp legit. The tone is amazing, and there's something to be said about being able to rackmount. I may have to think about picking one up for myself. Nah, I still like my Streamliner better.
Click to expand...

Thanks for the additional input tekdiver. That would be twice you got those results.
Sounds like something was possibly wrong with both test amps ampeg provided?

This is all too interesting. Thanks again, and your friend as well for letting you test his amp.
 
#140
Those results seem to be what would be expected, looking at the specs Ampeg lists:

• RMS power output:
• 1000 watts @ 4 ohms
• 600 watts @ 8 ohms
 

Latest posts

Top Bottom
Back