Bass testing your favourite amps

[Ian Mackenzie]

This has been discussed many times before and bound to bring in many amps busters.

Why Do so many amps sound different in the bass area?

Okay allow me to qualify that, we are talking about quality amps, not so called multichannel wonder boxes and B grade consumer boat anchors.

I recall a post recently where it was reiterated the quality of the power supply capacitors was the key.

Oh really?

Maybe for some amps, but not for others.....switch mode amps and other new classes, and perhaps even the tried and proven class A room heaters.

Go here for a full explanation on power supply upgrades.
The job of filter capacitors is also well explained here.
http://www.tnt-audio.com/clinica/solid-state.html

They act like a water reservoir tank, you pour water in and take water out, to a point the bigger the tank the better the capacity to cope with demand.

Its also interesting to determine if the current demanded by the amplifier is constant or dynamic. As a rule, a constant load is a much tougher job for the filter capacitors because of the higher AC ripple current demanded.

However, the impact of capacitors dynamic performance is far less pronounced on an amplifier that draws a constant load, where the supply rails remain relatively stable and the design has good PSSR and CMRR.

With this in mind I recently did some comparisons with a conventional A/B amplifier, a class A SE amplifier and a 3rd class A amplifier having a true balanced output stage where the speaker output comes directly from the power transistors, not via the power supply.

The subjective appraisal for the conventional A/B amplifier provided tight punchy deep bass, however there was obvious bloom and colouration in the upper bass and midrange, it had large power reserves but lacked subtle nuances on bass instruments. (Damping greater than 1000 @ 20 hertz and output greater than 300 watts).

The class A SE amplifier exhibited an enlightened ambience in the bass and a feeling of space, individual instruments were clearly identified. There was a slight warmth in the tonality and good control of drum notes. (Damping factor 80, power output 100 watts).

The full balanced class A amplifier showed impressive dynamic contrasts, 3 dimensional ambience and tantalising excitement of micro dynamics. The bass tonality was neutral and delineation of instruments outstanding. (Damping factor 30, power output 100 watts).

Obviously I expect most will take this with a grain of salt and perhaps this belongs on another forum (although I would be preaching to the choir.) It would also appear damping factor is not the sole criteria for good bass performance.

But I think its fun to challenge your equipment and your ears occasionally.

By the way, the joke of this experiment was the reference speakers which were set up in near field operation. They are the much loved and unfortunately much bashed L100 Century.

The moral of the story is except nothing as normal, blame the operator first and your speakers last.


:eek:

[PSS AUDIO]

Originally posted by Ian Mackenzie
I recall a post recently where it was reiterated the quality of the power supply capacitors was the key.

Oh really?


Hi all of you,

When something is said about power amplifiers, here I am!

All what will be said lies for AB amplifiers only.

From my very little experience since 25 years from now, I can say that what is important in the quality of an amplifier is the following:

The way the transformer is winded (we have several transformers able to deliver 2x300W, their power ability lies from 200Va to 1200VA; all listening test made around 25-30 watt, witch means that all transformers are powerful enough to drive the requested power).

The bridge is also important. Once we have selected the right components (transformer, capacitor, and others) changing the bridge will affect the output tonality.

Capacitors: From one brand to another, even with the best technical characteristics, you will have different tonality using one brand or another one (we finally went for several 10000MF100V capacitors instead of a big one – 47000MF63V from BC COMPONENT). One was nice but too shinny with a lack of mid bass … guess witch one?

It is well known that replacing a power supply made by a transformer, bridge and capacitors by a battery will dramatically enhance the sound quality of your amplifiers and pre amplifier.

Gain: the gain of the amplifier IS very important as we recently switched from 32 dB to 26 dB.

Signal to noise ratio: This is perhaps one of the most important number and greater it will be; more micro details will be heard, and by lowering the gain of the amplifier you will increase his signal to noise ratio.

CMRR: If you have a balanced input it is important having the better CMRR possible in conjunction with the signal to noise ration.

After that the choice of good resistors, capacitors (void all capacitors in the audio link) the way the PCB is designed will also play on the tonality of the amplifier.

Only A or AB amplifiers can play good music (other will just make noise, good enough for a football match in a stadium or for the next Olympic Games in Athens),
Distortion has no real signification,
Damping factor is just nuts,
Slew rate is not that important as the rising time (there is a house …. The animals),

This is just the beginning, for others climbing up the train just read a thread I opened month ago “Amplifiers are more significant than you may think”: http://audioheritage.csdco.com/vbulletin/showthread.php?s=&threadid=347

[4313B]

Ian,

Did you ever run across this - http://www.stereophile.com/amplificationreviews/674/

Also, what all did you see at Pass Labs?

[4313B]

Originally posted by PSS AUDIO
Damping factor is just nutsHere we go again. :nutz:

I'm not quite sure how a ratio of two numbers can take on a psychological "disorder" but here's what George had to say about DF way back when - The Damping Factor Debate (http://lansingheritage.org/html/jbl/reference/technical/damping-factor.htm)

It appears certain Marketing departments decided that damping factor was a "figure of merit" and we've been plagued with it as a selling point ever since.

[PSS AUDIO]

Originally posted by Giskard
... but here's what George had to say about DF way back when - The Damping Factor Debate (http://lansingheritage.org/html/jbl/reference/technical/damping-factor.htm)



We placed the same article on our website : http://www.pssaudio.com/english/art010.htm

I was perhaps misunderstood.

When I say nuts, it is between 17 and an infinite value, manufacturing an amplifier with less than 17, one must be ... very bad unless using an output transformer of poor quality!

It is not because an amplifier will "show" a DF of 100000000000000000000000 or even greater, that it will handle bass properly!

Neither if an amplifier has a DF of 20!

[Ian Mackenzie]

Well that did something, Jeepers

But the L100 misses the limelight again, Where are Bo and Tooths when I need them? Presumed missing in action.

Reading the links to other threads, high damping factors and particularly varying with frequency may not be a good thing.

Giskard, thats a nice review of the Aleph 3 and actually made one a while back. If you want a nice amp for your 4435 to biamp, thats the one.

I saw many nice things at Passlabs, its was like a memorable experience, just watching the them build those great big poweramps. The biggest I saw was an X Series 600, thats a 600 watt mono block...this kinda say it all....a total mind f$%K

The output follower stage consists of 48 power Mosfets per channel for a total of over 7200 watts short term dissipation. The power supply features a single massive toroidal transformers rated at 4 KVA, and over 180,000 uF of storage capacitance.

Damping factor 60 ref 8 ohms nominal

This stuff sounds really good as I found out at the invitation of Mr Pass.

Ian

[Ian Mackenzie]

I am not here to promote Passlabs by the way but they seem to mate well with JBLs.

Giskard, are you aware of Gt's attitude to amps and bass?

Ian

[4313B]

Originally posted by Ian Mackenzie
Giskard, are you aware of G.T.'s attitude to amps and bass?I'm pretty sure he likes bass, and I think there are a few amps out there he likes as well. :D

[John Nebel]

Originally posted by Ian Mackenzie
I am not here to promote Passlabs by the way but they seem to mate well with JBLs.
Ian

Pretty interesting price on the XA200!

Definitely in the audiophile range.

John

[PSS AUDIO]

Originally posted by Ian Mackenzie
The output follower stage consists of 48 power Mosfets per channel for a total of over 7200 watts short term dissipation. The power supply features a single massive toroidal transformers rated at 4 KVA, and over 180,000 uF of storage capacitance.


I am not here to promote PSS amplifiers but those numbers are quite normal as our next studio amplifier (2x150W/8ohms) will receive:

2 x 1600 VA transformers,
2 x 100 000 MF of storage capacitors (and perhaps more if we have some extra place on the PCB),
2 x 6 output transistors (MJ15024) for a total of 7200 watts LONG term dissipation - 5A per transistor, it means 30A²x8=7200W per channel!

Those numbers are made for the catalogue and it does not mean that an amplifier with such numbers will sound GOOD!

Our will do ... from what we are said by several listeners!

And his pricing is very honest!

[Ian Mackenzie]

Well the off topic now is going off topic.

I though the comment in the literature about keeping some resisters handy in a pocket was interesting.

I think the DCR or DCX as referred to in some literature, has to be taken into account when we are trying to assess and subject bass performance.

ie DCR can be a good thing, an it can be a bad thing.

If the drivers have un avoidably low QT its certainly one way to retune the enclosure, I did that with the Altec 515, the Qts was 0.17 as I recall.

I doubled the Dc of the voice coil an ended up getting a usable response without having to resort to mis alighment

The effective damping at FB appears to be sensitive to amplifer damping at least with some speakers.

I have tried this with the 2245 woofer, but we are talking a magnitude of 0.5-0.8 ohms added DCR, thats 6 5 - 10% the value of the impedience, and 10% to 15% the coil DCR.

The differences below 0.3 ohms added DCR are less discernable but sublte tonality and bass extension rather than bass over hang, for a nominal 8 ohms thats a Damping Factor of 26.

Of course we are talking about added pure DCR to the exisiting network which in reality is not always the case. Depending on the speaker system and tuning, there most likely will be a threshold where the effect of DCR is such that it causes noticable ripple in the low rolloff response ( a bit like tuning the box a bit too high).

These effects can be simulated in BassBox, and have to be considered with the box losses (fibre glass & leaks)

Ian

[Mr. Widget]

Hi Yuri,

Since you are in the amplifier business I assume you have had a listen to the Pass Labs products. I know that Nelson Pass's stuff is audiophile and not Pro Sound, but it is highly regarded in both worlds. I have seen manufacturers use the Aleph amplifiers at AES Conventions to best show off their speakers or other gear. In fact Sony/Phillips used five or six of them to showcase SACD a few years back before SACD was released.

What are your impressions of the Aleph and other "High End" amps?

Widget

[Ian Mackenzie]

Yuri would need to locate a Passlabs dealer for a demonstration , they can be found at Passlabs.com.

The Aleph series has won countless awards in hifi circles. The newer X Series are far more powerful, up to 1000 watts and beyond when used together. They are benchmarks for Stereophile and Absolute Sound. The latest AX version uses concepts from both the Aleph and the X Series.

Okay, here is an idea, I will have a look on diyaudio for a member who is in Yuri's area and see if we can organise a demonstration of a Aleph amplifier.

Yuri, where do you live, drink red wine and entertain woman.

The Aleph is now discontinued line and the diyaudio members have built some Aleph amplifiers for diy purposes. The design remains the interlectual property of Neslon Pass, however he is such a gentleman and a generous scholar of diy that he allows us mere formites to enjoy sharing his vast knowledge.

The fact that I was able to met Pass at his firm in the Sierra's and tour the Passlabs facility was a rare treat, and then hosted some evening entertainment at his house, that was special.

He is known in the industry as the Wizzard.

Pass started out his career in audio designing crossovers for ESS, he then went on to form the Threshold Corporation, Telarc used the renouned Stasis amplifers for their cutting heads, in the early 1990's Pass formed a new company by his own name. From what I could gather Passlabs is one of the few hi end amplifer manufacters that has survived and flourished without entering the home theatre market.



Ian

[Ian Mackenzie]

I would love to hear from anyone else who has evaluated any amplifers for the purposes of bass peformance.

Perception is 9/10 of reality after all.

I recall the much loved Crown 300A was well regarded for bass end being able to drive 2 ohms, and in the same era the Harman Kardan 16, the kit version of the Dynaco 400 (Rob has one I think), the Marantz 510 monster, the Sae range and of course the Phase Linears.

These days big power amps appear to have shrunk physically and grown in power. Such is the pace of technology and economics, but a BIG amp is a real turn on for me,and the girls likem......hey mate, I bet that one's got Big Balls. Yep.

Unfortunately, power and it would appear finesse do not necessarily go hand in hand

Actually, John Nebels nice Macs are BIG and they are transformer coupled. I recall the bass was quite articulate on all his wives.

Perhaps John can give a us a run down on the Macs and his recent experiences..

Ian

[johnaec]

Originally posted by Ian Mackenzie
I would love to hear from anyone else who has evaluated any amplifers for the purposes of bass peformance. Well, some of us here are sold on Crest amps, (at least in any range I can afford). I'm also a bass player, so I'm always interested and highly critical in that area. And though I really like them for general stereo also, I haven't ever done any really low-level listening, where undesirable artifacts would be most noticeable. But IMO they can't be beat for real honest output when driven at maximum for hours on end, and also for general stereo use... Note that since selling out to another "beatrice foods" of the audio industry, Crest now also makes lots of other low-cost amps that probably aren't worth looking at too much... But their top of the line stuff is real good.

John

[Ian Mackenzie]

Cool John,

I once saw a rack of Crest amps here for a local beach party, the mobil generator on the back of a semitrailer was singing in tune with the bass guitarist The 3 phase from the rack was warm.

Can you post ue a picture of your amp.

Ian

[John Nebel]

Right Ian,

After a good amount of Chimay ale, I'll make a lot of sense about amps. Maybe tomorrow, or take the following with a grain of salt.

Macs cost about 10%/watt of the cost of the Pass amps and produce quite a decent sound.

In some realms, ie. computers, where absolute reliability is an issue such cost factors with minimal performance gain, 10x is likely justified as the Royal Bank of Canada recently illustrated. (Or the British Air Traffic Control System)

The Pass amps look great and in some envrionments, that could be the deciding factor. The design and execution is really neat and that is great.

I've always thought the real issue with an audio system was the speaker and hence JBL.

Your friend,

John

PS

Being a true conservative, I like the idea of a transformer between the power supply and the voice coils.

[Ian Mackenzie]

John,

Great you here from you,

Be careful of that ale, its a strong drop of amber, but nice.

I recall drifting into a quiet lull sipping that stuff in front of the wall of sound. Bo played the same trick on me with some California Red while listening to his 4345's, then he beat a confession out of me.

I told him what I thought which was what he wanted to hear , I mean how could I lie about speakers I own, I mean built. Damn Yankee.

On the transfomers, I recall your conservative stance was more akin to the memory of a splat of Dc potential difference across the voice coil of the JBLs and of the combustion that followed.

No names about your previous amps, they just passed away gracefully, we don't want to give the tribe indigestion.

Pass caters to the taste of Japanese market and price budds, I suspect thats a carefully blended formulae.

Ian

Ps. Have you fired up the 260 yet?

[scott fitlin]

I like my bass, if your playing a recording with good music, to sound what it would sound like if actually listening to the musicians themselves! Or close enough to it!

Crown DC-300A. I grew up on these and they did do bass very nicely. That little extra grunt on the bottom, due to direct coupled design! But Im needing more power these days, the drivers today are made to operate with more power.

Crown PSA-2. Lots of rumble, thunder, and punch, and did two ohms mono all day long! So thats like 1 ohm per side. But things dont last forever, especially running 14 hours a day here!

Crest 7001,s and up. Well, I always stuck to Class AB designs, but what can I say? Crest sounds really good, especially for bass. Warm, round, punchy, articulate, strong and powerful, and they run all day long! Of ALL the NEW technology amps these days the Crest Pro Series ( expensive ones, lol ) does the do! Other makers 2 rackspace weight saving jobs offer lots of 1kHz power, but many are a bit shy sounding on the extreme bottom. Not the Crests, they get down, and boogie, cleanly too! We were listening to an old Hector Lavoe cut the other night, and the way the bassline sounded was the way it sounds when you hear a bassist play! My mngr Miguel said ya know Scott, that sounds like the guy playing the Fender Jazzmaster! I agreed, and we both said it didnt sound like this through the Crowns!

Crest has a warm, heavy tone, but is clean, and it works! I have been running three amps now for a couple of weeks so I am convinced they do in fact work and play great!

When I went to place my order for my new 15,s they were doing a demo for a potential customer of a sound system. All Crown macro tech powered! They had four folded horns, two per channel of the Crown Macro tech 5000VZ, and while it had lots of punch, it lacked roundness that I like in my bass sound! Simply said, although the 5000 has alot of power, it wasnt the sound I was looking for. I knew I wanted to get back here and listen to my Crests, and jones for the rest of them to arrive! Then, they hooked up the same four folded horns to the latest offering from Crown, the I-Tech 4000! I thought the macros were a touch thin on the deep bottom, well, this was even thinner! And I thought the Crown I-Tech lacked musicality! Musicality is important to me. So, Crest has my vote! I suppose that the I-Techs, with their onboard DSP speaker mngt system and very high power levels will appeal to some companies looking to reduce the amount of componentry, and weight.

PSS Audio. I would love to audition one of the PSS Audio amplifiers! 1200 wpc of Class AB power is appealing, but no one I know here has the line of PSS products! Nor does anyone I know, know anything of how the amps sound, I am sure they work, but, and this is just as important as sound quality to me, if the amps arent really available here in the U.S., service and support isnt here to back the product up, either! I mean, IF an amp goes down, and it happens from time to time, but not often, I can get fast, factory service, for Crest. My tech shop knows the crest amps well, and can repair them should this become neccesary. Yuri, my system is an entertainment system, in a buisiness, and technical support here in the U.S. is important too! I dont doubt what you say about your amplifiers, but if you want sales here in the U.S. you need a distributor, with a network of retailers, and service support for your products here in the U.S., too!

All in all, I am digging my new Crests, and cant wait for the rest of them!

:cool:

[Ian Mackenzie]

Scott,

I can relate to your experiences. Were you playing vinyl ?

Rob took me over to the Downtown to hear Steve Howe play when I was on Long Island. They have a big Crown Macro-Tech installation, I recall they had a rack for of 5002's? and a smaller one. Its was very clean, crisp and dynamic but beyond that I could not comment.

Over hear I have heard a Mackie 400 watt mosfet amp and Australian monitor mosfet 1k2 going flat out into some JBL System 700 boxes and while they had the sweetness of the typical mosfet sound in the highs, the bass did not really get up and boogie and sounded compressed in comparison to my grand Daddy Phase Linear 700. (they are popular with bass players)

If you really need large amounts of power, A/B is the only viable alternative. But on my domestic front I plan to experiement with modest class A amps (under 100 watts) for a 4 way 4345 active affair soon enough and see what happens.
.
The one thing I have come to appreciate, particularly with a 4 way passive system, is that you can create a crisp, fat or thin bass sound by making subtle adjustments to the level pads.

But there's more to it than the flatness across the whole spectrum, the overtones can really shape our perceptions about bass, and if they are scewed up it can become tiring after a while.

I will keep my eye out some of Yuri's amps, I recall seeing them via an Ebay link to an outfit called Cannon Sound down here

I am sure the PSS are a fine sounding amp but I am more interested in the quality of the first watt of power with 95 db sensitivity speakers (with 107 db horns & 105 db slots) rather than the last watt.

That 's why I am wedded to class A, at least until a new class of amp is discovered that can do it better.

Ian

Ps Bo the artisan Knob Farmer is away. But I am sure he will give ample evidence on his QSC amps when he is around.

:rolleyes:

[scott fitlin]

I hear you, but I have several macros on hand, 3600,s and 2400,s and they never satisfied me like the older generation of Crowns. I also had a set of macro tech 5000,s and sold them. That ODEP circuit. I hate it!

Class A is great, always was, always will be, but, its impractical to use here in my place. The heat, size, and power factors would limit me to using Class A for mid horns and tweeters only!

Phase Linear 700B. Always a perennial favorite among musicians, pros, and Hi Fi nuts alike! Massive power transformer, this thing outdoes a DC-300A no problem!

The Crest sound does what I like bass to do! Big power, big bass sound, clean, and clear notes. But, I will use only a bryston or Crown D-150 or Mc 2125 on my mid horns, and stay with my Crown D-75,s on tweeters!

its all a matter of preference! And yes, i play vinyl, but I play CD,s these days too!

:cool:

[PSS AUDIO]

Originally posted by scott fitlin
PSS Audio. I would love to audition one of the PSS Audio amplifiers! 1200 wpc of Class AB power is appealing, but no one I know here has the line of PSS products! Nor does anyone I know, know anything of how the amps sound, I am sure they work, but, and this is just as important as sound quality to me, if the amps arent really available here in the U.S., service and support isnt here to back the product up, either! I mean, IF an amp goes down, and it happens from time to time, but not often, I can get fast, factory service, for Crest. My tech shop knows the crest amps well, and can repair them should this become neccesary. Yuri, my system is an entertainment system, in a buisiness, and technical support here in the U.S. is important too! I dont doubt what you say about your amplifiers, but if you want sales here in the U.S. you need a distributor, with a network of retailers, and service support for your products here in the U.S., too!

:cool:

Hello Scott and all others!

The fact is quite simple: We, at PSS are a "small" company compared to Harmann and other “monster”.

The US market is half of the worldwide market and if a brand is introduced in the US market either it is a mess or it is casino!

If it is mess what is the use trying the US market?

If it casino, we are not able delivering all the needs of the US market and if ever it happens we will be burnt till the end of our lives!

That is why I prefer getting the other 50% of the market, being strong enough before going into the US market!

Anyhow, what I am ready to do, for you Scott and Ian (read my next post) is to ship you for free an amplifier (you will have to pay the local taxes and clear the parcel).

You will be able listening at it, and printing here your report!

This can be very helpful for us (and if you need any assistance, we have our forum boards and all our technical data’s are on our web site, in such a case everyone can service a PSS amplifier).

[PSS AUDIO]

Originally posted by Ian Mackenzie
I am sure the PSS are a fine sounding amp but I am more interested in the quality of the first watt of power with 95 db sensitivity speakers (with 107 db horns & 105 db slots) rather than the last watt.


Ian,

I think PSS amplifiers sounds good from the 1st watt they deliver!

As I know you are a class A lover, let me suggest you the following.

As you know we have an excellent distributor in Australia, NET.

We must ship him in the next 2-week time some amplifiers.

I will add a PSS1200, same amplifier that I intend sending to Scott, and you can get if from NET.

Perhaps will NET ask you to pay a little something for the carriage and income fees?

Anyhow you will be able listening at it and printing a full report thus everybody can have a better idea about our sound quality.

Do you agree with this offer?

In such a case get in touch with me (Scott please do the same) and call NET (Billy Mawyer) to settle the case.

[Ian Mackenzie]

I have sent Yuri a pm.

Thankyou Yuri,

I am humbled, but please I am hardly a professional equipment reviewer but I will do my best and say what I hear.

It will be very interesting to see / hear your amplifier.

Ian

[scott fitlin]

Yuri I have sent you a PM, and I look forward to reveiwing your product!

[PSS AUDIO]

Scott,

Well received!

A PSS1200 is leaving next Monday and in a week time UPS should ring at your door (I hope so)!

Why not opening a thread just for this review?

Why not lending it to other users in the US once you performed your "review"?

We can talk about it.

This amplifier is not intended to be sent back.

Ian will receive one too with our next shipment in Australia.

All I ask is to post your comments on our forum board too!

[Ian Mackenzie]

Looking forward , or should I say back to the "Future" I recall the impact of biamplifing my first speaker system.

But should we call this " Bi amping" or "The Wow factor?"

Surely its the bass addicts favourite past time.

Its been a while since I bi amped, but the truth was bought home to roost when I heard Bo's 4345s biamped with his much loved QSC amps during my visit to the USA.

Without a doubt I was "impressed" with the bass performance of this system. I mean hello it just doesn't get any better than this.

Either the 2245's or the amps, it don't matter, that system just disolves before your very eyes. Why?

Its one thing to talk about damping factor, but the dimension of authority, power and the room ambience it creates does take some figuring, and there is no sub woofer in this system.

The perceptual cues of effortless bass really makes the difference between an audition and " an experience" IMHO.

I suspect the whole manner in which the "a system" is set up by way of enclosure positoning, the geometry of the room and careful attention to room equalisation has something to do with it.

So, is it about the numbers and the amp you chose, the decison to bi amp or the way you went about it that provides musical enjoyment?

If you have been there, done it or thinking about it, your comments are most welcome

Ian

[scott fitlin]

Not only do I intend listening to this amp on my system, but I already have plans to lend the amp to two different people with systems to listen as well.

Talking is one thing, putting it in someones possesion to use themselves is another, so...............



:cool:

[PSS AUDIO]

You can prepare a set of good balanced input wires and output ones with Speakon plugs!

[Ian Mackenzie]

Yuri,

I have balanced preamp outputs and speakon connectors so I am ready.

Ian

[PSS AUDIO]

Originally posted by Ian Mackenzie
Yuri,

I have balanced preamp outputs and speakon connectors so I am ready.

Ian

Ian,

With TEAC CD players, and perhaps others, you can void the preamp and link it directly to the amp, as there is a volume control on it!

[Ian Mackenzie]

That's on the agenda.

Ian

[PSS AUDIO]

Dear all,

We shipped this morning a PSS1200 to our friend Scott in Brooklyn!

You can track it (ups.com) with the following # M0592094943

For all characteristics please follow this link: http://www.pssaudio.com/english/amps.htm

[boputnam]

Maybe a typo, somewhere, Yuri...?

[PSS AUDIO]

Originally posted by boputnam
Maybe a typo, somewhere, Yuri...?

Typo is good!

Check the link: http://wwwapps.ups.com/WebTracking/processInputRequest?HTMLVersion=5.0&loc=fr_FR&Requester=UPSHome&tracknum=m0592094943&AgreeToTermsAndConditions=yes&track.x=22&track.y=9

[boputnam]

"typo is good" = no typo! I get it! :yes:

Cool, so where will Scotty install/try this - at the still-to-be-pictured arcade, or the home environment...? :hmm:

[scott fitlin]

I am going to put it in here, on the bumper car sound system!

[boputnam]

Hey - dju ever figure out how to post some pics of Eldorado for us...?

[PSS AUDIO]

Originally posted by scott fitlin
I am going to put it in here, on the bumper car sound system!

It also deserves an audiophile use as this amplifier is very close to our studio one!

A description of your testing method is welcome as the one used by the person that will review the amplifier.

[scott fitlin]

This amp will be connected to a pair of double 18in loaded scoops that have JBL 2240H woofers. I will make the necessary adjustments, and then proceed to let the amp work and settle in for a day, after which I will listen over a weeks period of time to the amp and the sound it makes!

I have found that I usually listen to things for a solid week before making a decision, and this is generally sufficient for me!

The Polar Express,s sound technician has expressed interest in the amp, so it will go there after I have had it, and listened to it!

Then the amp will make its way to Shorty,s house, where he has a system in his basement, for his opinion.

So this amp will be making the rounds!

Of course, should anyone else wish to hear the amp, and is within distance, I will make it available!

[PSS AUDIO]

Originally posted by scott fitlin
Its the smaller, more sensitive amps that sound great on JBL tweeters. I have had big amps with 1.5v input sensitivity and it doesnt work well from 7K and up for me. The little amps give me a far more delicate sounding top end, and the tweeters sound sweet!

It means that those amps are not able giving nice and clean watts from the first milliwatt!

When you will have the 1200, make a try with it in the high and let me know ...

[PSS AUDIO]

Scott, Ian and all others ...

The amplifier is in Roissy terminal, hope it will be next morning at JFK!

[PSS AUDIO]

Scott,

The amplifier is in Philadelphia (local time 11:21)!

[PSS AUDIO]

Hello,

The delivery is scheduled today!

On your marks, ready, steady, GO...

[PSS AUDIO]

From UPS records, the amplifier was delivered at 10:30!

[boputnam]

So, I guess we're all hoping it's 120v/60Hz, compatible... :eek:

[PSS AUDIO]

Originally posted by boputnam
So, I guess we're all hoping it's 120v/60Hz, compatible... :eek:

Bo,

I never taught about it!

Hummm .... what to do?

120V still exists?

I'm pulling your leg!

Of course it is and this PSS1200 was even switched on 115V as all PSS amplifiers are internally 115V/230V switchable.

How many amplifiers provide such a mode?

Not that much ...

[boputnam]

Yuri, you've taught of everything!! :thmbsup:

[PSS AUDIO]

Originally posted by boputnam
Yuri, you've taught of everything!! :thmbsup:

Bo,

I am the best, that is why I don't compete :smthsail:

[scott fitlin]

I got the PSSAUDIO amp today, and am preparing to install tomorrow! Also recived literature, and spare ALPS pots!

Yuri, one little question! I will run the amp on a pair of double 18in JBL 2240H loaded scoops, this I know the amp will do no problem. But, lets say I also wish to hear this amp on my J-Horns, will this amp do 2 ohms per side?

[scott fitlin]

I am just getting to reading the literature, and it seems you sent me the 1200! If this is in fact the 600wpc amp, I will try it on my fifteens, mid bass range! Much more audibility, and critical lower mids! This will tell the tale!

:cool:

[PSS AUDIO]

Originally posted by scott fitlin
Yuri, one little question! I will run the amp on a pair of double 18in JBL 2240H loaded scoops, this I know the amp will do no problem. But, lets say I also wish to hear this amp on my J-Horns, will this amp do 2 ohms per side?

Scott,

Unfortunately or hopefully no, PSS amplifiers do not run with 2 ohm loads, as I honestly doubt one can make some real good music with such low loads...

Yes the amplifier I sent is a PSS1200, delivering 600W+600W (as it is a twin mono amplifier) with 4 ohms load.

You can grab all the technical characteristics here: http://www.pssaudio.com/english/amps.htm

I'm impatient reading your very first comments!

[boputnam]

...sports fans! Nice!

[PSS AUDIO]

By the way, if you want a paper catalogue, just request one (with full name and address) at the following: [email protected]

[boputnam]

Hey, Yuri...

Looking at the connections, it looks like you've got parallel inputs - XLR in (f) and XLR out (m), for ganging? :hmm:

[PSS AUDIO]

Originally posted by boputnam
Hey, Yuri...

Looking at the connections, it looks like you've got parallel inputs - XLR in (f) and XLR out (m), for ganging? :hmm:

Bo,

You are 100% right!

[scott fitlin]

yes, it is indeed the PSS1200! 600wpc@4ohms! I have unpacked the amp, it does look nice, and I am running to the store to buy speakon connectors. My system outputs are bannana plugs. Did I mention I hate speakons? No I guess I didnt!

However, since this is the same range of power Im currently upgrading to on my midbass, this is where I will audition this amp! 1.5v input sensitivity is right. Power is right. And I will get to hear this amp perform in the low frequencies as well as the low mids! In this range I should really be able to hear what this amp is all about, it will go into the rack this evening after I close, at which time I will give it a general listen. No serious listening until tomorrow!

I was looking at the picture of the cooling system and I like the way you have the fan draw air right across the output transistors! Look like a good cooling design!

Pretty amp!

[scott fitlin]

You dont specify wether the positive input is pin 3 or pin 2! I will assume you are pin 2+, but correct me if its not!

That faceplate is very white!

[PSS AUDIO]

Originally posted by scott fitlin
You dont specify wether the positive input is pin 3 or pin 2! I will assume you are pin 2+, but correct me if its not!

That faceplate is very white!

Scott,

Have a look at the label delivered with the amplifier (unless it was forgotten while packing it)!

Everything is printed on it… You can stick it above all the plugs (have a look at the picture Bo posted).

You can also grab the users manual from our web site!

XLR wiring (balanced use) :

1= ground
2= plus
3= minus

If you want to run the amplifier with an unbalanced input, you must join 1 and 3

Outputs are:

1+ and 1-

About the face plate, read my story about snow white: http://www.pssaudio.com/forums/index.php?showtopic=6

[PSS AUDIO]

Originally posted by scott fitlin
1.5v input sensitivity is right. Power is right.

Pretty amp!

Scott,

Since the brochure was printed, we made 2 modifications.

The input sensitivity is 2,3V by now (26 dB gain) and there are 80 000MF of mains capacitors instead of 40 000MF!

[PSS AUDIO]

What about opening a dedicated thread by now?

[Mr. Widget]

Do it!:yes:

[Ian Mackenzie]

Yuri,

Can you advise the status on the deliver of the PSS 1200 to your distributor?

Ian

[boputnam]

Originally posted by PSS AUDIO
What about opening a dedicated thread by now? In one way or other, aren't they all, anyway...? ;)

Anxious to get some test results. I fear we've lost Scotty to the PSS - like something from Forbidden Planet...

[PSS AUDIO]

Originally posted by Ian Mackenzie
Yuri,

Can you advise the status on the deliver of the PSS 1200 to your distributor?

Ian

Ian,

We must ship him some goods next week or so. We will prepare a PSS1200 (same as the one for Scott, hope we hear from him soon) thus you can test it too (the amplifier, not Scott)!

[Ian Mackenzie]

Thanks Yuri,

I look forward to the evaluation of the amplifier.

Ian

:)