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alexkerhead
10-23-2006, 11:45 PM
I managed to pic up a Pioneer sx-1250 on ebay working in good shape for $225+$60 shipping.
I know it has 165wpc, but has anyone had any experience with this receiver?

How do you think it will handle 4x L100s?

Rolf
10-24-2006, 12:37 AM
I know it quite well. A "fair" price, if it is working ok.

Not 4 L100's. but 2. Remember much of the amps of that time does not like 4 Ohm's.


I managed to pic up a Pioneer sx-1250 on ebay working in good shape for $225+$60 shipping.
I know it has 165wpc, but has anyone had any experience with this receiver?

How do you think it will handle 4x L100s?

pioneer
10-24-2006, 01:01 PM
I also have a SX1250 that I bought new that I stilll use with L100's. It is an excellent workhorse and will be a nice fit with the L100's although I only used it with two. I think it would handle 4 L100's without any problem. I would suggest that you take it apart (pretty easy) and give the switches a nice cleaning as mine got very scratchy over the years and some of the switches started to seize up. It has a decent tuner and you can easily uncouple the amp from the tuner/pre-amp section . Nice price

alexkerhead
10-24-2006, 09:24 PM
I noticed the xx50 series has serious control problems like you said.
I deoxited my mother's sx-1250 a week ago(three hours of work, but I also cleaned inside and out as well), huge pain, but well worth it, at least I have some practice with that unit before I do mine.:)

pocketchange
10-28-2006, 07:04 AM
I have SX1250's for torque and I have NO problem driving 2 pair of speakers.
For your comfort (and peace of mind) I'd suggest finding a good tech and having the bias checked as there are a few minor age related issues that may have to be delt with. A good idea is to keep an eye on the sinks and if the overload ever kicks on you will need to find a tech. Looking at the big caps would also be a good idea (and give you a chance to see if they are leaking).
Minor ooze is normal (an age related problem) and keep in mind if the unit is quiet and not humming or getting hot you most likely have a great piece of gear that will continue to give years of enjoyment.
FYI: The BIG Replacement caps are available..
PN's from Nickosan (SP) 36DA223F100CD2A (typically $150 for a set of 4)
Also: check the AudioKarma Forum - Pioneer thread- for info and look for threads from member EchoWars, he knows his stuff.
You stole this SX for what you paid, specially if it's clean.
pc
:applaud:

Rolf
10-28-2006, 12:06 PM
I have SX1250's for torque and I have NO problem driving 2 pair of speakers.


You probably don't push it. Do so, and the transistors burn up.

pocketchange
10-28-2006, 02:29 PM
The reference to having the bias being checked is what I was refering to to insure you don't run into the transistor problem. Also keep in mind the transistors on/in the bias control will need to be removed to have their value verified. Unless you have an auditorum or bad hearing the SX1250 has a built in circuit that simply will turn the unit off if thinks get too hot (which I have never had happen when the bias circuit [transistors and such] is working properly). :blink:
Under a load would be having the volumn past the 1 O'Clock posistion. Anything past that and ear muffs are necessary or you will end up with diminshed hearing.
A trip over to the Pioneer Forum will find a spec. breakdown on some of the features of the SX Series if you are interested... :blah: :blah:

spkrman57
10-28-2006, 02:40 PM
The 123A woofer in them reach down to around 5 ohms, with 2 pairs would have a paralleled total down to 2.5 ohms.

That would be below the 4 ohm min rating.

In series would be okay, not saying it would sound good that way or not.

There are threads on this forum where I read the info. Do a search for 123A and you will find them.

Regards, Ron

alexkerhead
10-28-2006, 08:37 PM
I am a amatuer tech, i checked the mV, it runs 10.2 on the left and 11.4 on the right channel, well within safe.
The caps are registering a bit low on a capacitance meter my friend has, about 19,200uF, and they should do 22,000uF.
I checked the output power and it is 12watts below the 165watt rms at 8 ohms.

The output transisotrs will be getting new thermal compound when I replace the capacitors. I am ordering computer grade 22,000uF 100V capacitors from mouser for it.

If the SX-1250 has too much resistance on it, the speaker protection kicks in to save speakers and the transistors.
It also has a thermal control circuit, so it shuts off when it gets too hot.

I have been playing with this unit until I can afford the capacitors, and I must say, this thing blows me away, the bass is solid and controlled, the mids and highs have no distortion at high volume.
Sound is clean and even.
At 4ohms it runs about 194wpc(should be 200wpc).

This unit can handle 4ohm no problem from what I hear.
It is supposed to be the most reliable monster receiver ever built from reputation at AK. I am an AK member and have asked around there as well.

This thing is amazing!
Here are some pics.

Pics (http://www.ubertechworld.com/images/hifi_setup/sx_1250/)

(http://audiokarma.org/forums/showpost.php?p=863386&postcount=1)

Rolf
10-29-2006, 12:31 AM
:blah: :blah: is not good enough. Push it with more than 2 speakers, and it will burn, no matter technical adjustments being done. That is just the way the construction is... So are many others of the time. :blah: :blah:


The reference to having the bias being checked is what I was refering to to insure you don't run into the transistor problem. Also keep in mind the transistors on/in the bias control will need to be removed to have their value verified. Unless you have an auditorum or bad hearing the SX1250 has a built in circuit that simply will turn the unit off if thinks get too hot (which I have never had happen when the bias circuit [transistors and such] is working properly). :blink:
Under a load would be having the volumn past the 1 O'Clock posistion. Anything past that and ear muffs are necessary or you will end up with diminshed hearing.
A trip over to the Pioneer Forum will find a spec. breakdown on some of the features of the SX Series if you are interested... :blah: :blah:

alexkerhead
10-29-2006, 12:42 AM
:blah: :blah: is not good enough. Push it with more than 2 speakers, and it will burn, no matter technical adjustments being done. That is just the way the construction is... So are many others of the time. :blah: :blah:
Do you own a sx-1250?

I am quite sure a bose 1801 or something with bad reliability issues would not handle the load, but Pioneers are quite famous for handling 4ohm loads without a hitch.

Be content in the fact that each L100 will start bottoming out at around 75watts rms, so therefore the receiver never gets taxed enough to cause damage.
150wpc is less than rated at 8ohm, at 4ohm is puts out 200wpc, so i have 50watt headroom at 4ohms.
This allows the transistors not to be pressured heavily.

Plus, nobody wants their music to bleed their ears, so I only use about 25wpc at loud volume per L100.

Now 6 L100s would be a problem.

Rolf
10-29-2006, 01:16 AM
Do you own a sx-1250?


Not anymore, and I do not want it back.



I am quite sure a bose 1801 or something with bad reliability issues would not handle the load, but Pioneers are quite famous for handling 4ohm loads without a hitch.


The bose ... well well.



Be content in the fact that each L100 will start bottoming out at around 75watts rms, so therefore the receiver never gets taxed enough to cause damage.
150wpc is less than rated at 8ohm, at 4ohm is puts out 200wpc, so i have 50watt headroom at 4ohms.
This allows the transistors not to be pressured heavily.

Plus, nobody wants their music to bleed their ears, so I only use about 25wpc at loud volume per L100.

Now 6 L100s would be a problem.

I have played the L100 with 200W ... no problem. ... But that is not the issue here, the 1250 is, and it can not ... repeate ... can not drive 4 ohms at high volume levels. ... and that is the truth.

Zilch
10-29-2006, 01:41 AM
123A-1 impedance:

< 8 Ohms 42 - 775 Hz

< 6 Ohms 59 - 255 Hz

Actual Zmin = 5.33 Hz ~110 Hz

WT2 states Zmin at 0 phase crossing:

alexkerhead
10-29-2006, 01:57 AM
Not anymore, and I do not want it back.
The bose ... well well.
I have played the L100 with 200W ... no problem. ... But that is not the issue here, the 1250 is, and it can not ... repeate ... can not drive 4 ohms at high volume levels. ... and that is the truth. You actually turned the volume all the way up on a set of L100s on 200watts?
I call BS.
You'd blow that L100 with a solid 200 watts in a heartbeat.
The voice coils simply CANNOT take 200watts.

I also don't believe you have owned a sx-1250, or else you would not have gotten rid of it. If you did, there was something wrong with it.

The only totl receivers I have seen that will blow under 4ohms are the suffixed DB sansui totls and the yamaha r-1000/r-2000.

My L100s cannot take but a little over half the volume this 1250 puts out before the woofers are bottoming. I found that out the hard way when I bumped the volume on accident.
Also, the 1250 will shut off the speaker relay when too much resistance is present, just so you know, you would have known that if you owned one.



Thanks for the info zilch, but since the L100s wont take full wattage at any volume, there is no risk of blowing the unit.

Zilch
10-29-2006, 01:08 AM
Be content in the fact that each L100 will start bottoming out at around 75watts rms.......

Rolf
10-29-2006, 07:27 AM
Oh my ... Ever heard the Marantz 512?

I rest my case.


You actually turned the volume all the way up on a set of L100s on 200watts?
I call BS.
You'd blow that L100 with a solid 200 watts in a heartbeat.
The voice coils simply CANNOT take 200watts.

I also don't believe you have owned a sx-1250, or else you would not have gotten rid of it. If you did, there was something wrong with it.

The only totl receivers I have seen that will blow under 4ohms are the suffixed DB sansui totls and the yamaha r-1000/r-2000.

My L100s cannot take but a little over half the volume this 1250 puts out before the woofers are bottoming. I found that out the hard way when I bumped the volume on accident.
Also, the 1250 will shut off the speaker relay when too much resistance is present, just so you know, you would have known that if you owned one.



Thanks for the info zilch, but since the L100s wont take full wattage at any volume, there is no risk of blowing the unit.

pocketchange
10-29-2006, 07:38 AM
Alexkerhead,
Why did you decide to use these?
pc

SEAWOLF97
10-29-2006, 10:06 AM
large , blue dial , silver face receivers. From my non=tech experience, the big Pioneer will certainly handle 4 L100's. These receivers, tho not "high end" , are still very well engineered and yours was from Pioneers golden years.

Look at their speakers and electronics from the last 15 years and the reaction is "YUCKY".:biting:

There is a website dedicated to receivers only, and they wont even discuss any later than 1990.
The position is that the black plastic stuff is a step down or two.(or 3)

Got no remote, but plenty good sounds......

regards
TOM

Audiobeer
10-29-2006, 10:14 AM
I had 2 pairs of L-65s hooked up to my Pioneer SX-1250 back in the late 70s. More recently I had a pair of L-300s as well as a pair of conrol 5s going at the same time (Out in the garage) at the same time. Mine had been completely gone through and never tripped the protective circuitry. It's a great value at that price. Mine was not blue faced.

Zilch
10-29-2006, 01:12 PM
Allow me to clairfy:

A pair of L100s is a load of less than 3 Ohms through a major portion of the LF range, dropping as low as 2.67 ohms, substantially as spkman57 advises above. That's specialized car amp and rare pro amp territory.

L100s don't seem to have an Xmax problem at 200 watts until below 27.75 Hz. Low bass EQ could easily get one into this territory at much lower overall power input levels. Nobody's advocating playing L100s at 200 W.

And now, because I consider myself entitled by investment, my opinion regarding this:

1) It's all, well..., "adolescent," to be kind, in the eyes of anyone pursuing excellence here.

2) It most certainly sounds dreadful.

3) Further, I have a bigger subwoofer than any of you.... :p

alexkerhead
10-29-2006, 01:19 PM
2) It most certainly sounds like crap.


What the hell are you smoking?

Storm
10-29-2006, 01:22 PM
What the hell are you smoking?

Apparently not the same thing you are smoking.

Hey GUYS - let everyone be to their own opinions. Zilch, back off!

Zilch
10-29-2006, 01:28 PM
Hey GUYS - let everyone be to their own opinions. Zilch, back off!Me too, ME too!!! :D

[At least I clearly identify them as such....]

alexkerhead
10-29-2006, 01:39 PM
At least I clearly state them as such....
No, you didn't.
You posted several result graphs generated by software you used with no opinion, and then when I made a logical assumption, you stated what I am doing is "adolescent" and my stuff sounds like "crap"
Even when you have never heard my setup, or much less had a similar setup yourself.

Get a life jerk, you lost my respect.

Edit: zilch is on my ignore list now, so no worries, I can't see his posts.

Zilch
10-29-2006, 01:49 PM
You posted several result graphs generated by software you used with no opinion....
WRONG, again, Alex.

At 1:36:17 this morning, I went and actually MEASURED a 123A-1's impedance to bring some potentially illuminating FACTS to this discussion, which you ignored and/or misinterpreted.

See also:

http://audioheritage.org/vbulletin/showthread.php?p=122946#post122946

Now, apparently, you are also an expert on cabinet refinishing:

http://audioheritage.org/vbulletin/showthread.php?p=131326#post131326

Do you believe for even a millisecond that you have ANY standing (see below) to advise on that subject in Technical Help, in the context of the expert work and experience of others (riessen, audiobeer, more...) here?

I WAS looking forward to you posting something that was actually correct in these forums.

Ain't gonna happen, obviously.... :(

http://www.ubertechworld.com/images/alex.jpg

alexkerhead
10-29-2006, 02:15 PM
Alexkerhead,
Why did you decide to use these?
pc
Computer grade capacitors are very high quality and should keep from degrading the sound. I believe they may even be better than the stock caps.

hjames
10-29-2006, 03:07 PM
Posting this to bypass the Ignore filter -
Dang Alex - Zilch has a test bench and has post MANY MANY significant, informed charts and postings here based on ACTUAL TECHNICAL Testing - not just some ... "hmhmhmhmhmh danged L100s sound real hawt with that danged classic Pioneer sauce ..."

No offense man, but - you are a newby here compared to many of the folks here who have posted regular, repeatable, informed knowledge in this forum. Folks who have thousands of dollars of scopes, sig gens and test gear - they really do know what they are talking about.

L100s are nice speakers - but - read your history - it was a mass market speaker that had a big appeal in the college crowd mainly due to the bass boom it produced. It was NOT accurate, just popular. Boom boxes! Its well known info.

If you like em, thats great - lots of folks do - but they are not the be-all, end-all of JBL speakers, and, relative to many of the more high end speakers these folks are used to (L300s and the 4343/44/45 series), they indeed are crap. Just most folks are too nice to say so ...
And thats just comparing a few of the tons-better speakers from that era.

So - mind your manners and give Zilch some credit, hmm?
I don't want to hear about another one of the knowledgable folks here driven off by some overenthusiastic newcomer who thinks 100 or so posts and a few pairs of speakers makes him an authority.

READ a bit of the posts here and learn a lot!



WRONG, again, Alex.

At 1:36:17 this morning, I went and actually measured a 123A-1's impedance to bring some potentially illuminating FACTS to this discussion, which you ignored and/or misinterpreted.

See also:

http://audioheritage.org/vbulletin/showthread.php?p=122946#post122946

Now, apparently, you are also an expert on cabinet refinishing:

http://audioheritage.org/vbulletin/showthread.php?p=131326#post131326

Do you believe you have ANY standing (see below) to advise on that, in the context of the expert work and experience of others (riessen, audiobeer, more...) here?

I WAS looking forward to you posting something that was actually correct in these forums.

Ain't gonna happen, apparently.... :(

http://www.ubertechworld.com/images/alex.jpg

Zilch
10-29-2006, 04:18 PM
Thanks, Heather. :thmbsup:

Alex:

I own L100s, study them, test them, think about them, try stuff to improve them.

Not bashing L100, but I found this post apropos:


The L100 is like some DIY'er just throwing drivers in a cab, capping them for a simple XO, and potting the MF/HF. Simple, fast and easy.

This thread tells the tale of L100 bass:

http://audioheritage.org/vbulletin/showthread.php?t=9463

The facts about the rest of it are easily accessible to anyone willing to do the requisite "Search" in these forums.... :yes:

Audiobeer
10-29-2006, 05:21 PM
Zilch has always brought quite a bit to thye table. He's a good guy believe me. The L100s are great Rock speakers, not very versatile however. They filled a nice niche in the market at the time. The SX-1250 was a great workhorse for driving them in thier day. I know a lot about the SX-1250 via many trial and error sessions......trying to bring back that sound I heard in my early 20s. I purchased several SX-1250s on Ebay and through the usual outlets on the internet. I never could quite recover the slam that I recalled. The SX-1250 at that point became an obsession and I shipped it off along with several other items in the past 5 years such as a Marantz 2270, and a Sansui AU-919. All three of them were gone through and had all tyhe Caps replaced as well as matching output transformers. All pots were replaced and everything was biased and brought back to better than specs. Unfortunately they never came back to what I remembered. They never had the bass slam they used to or the sound that I remembered them as having in thier original state. Further more they didn't have the same sound they had more recently prior to the upgrades. Was it because my listening capabilities changed? I think that had a lot to do with it although I don't like to admit it. When you change the parts you change the sum. I love bringing items back from the dead or dying but the truth is it's not financialy smart nor is it the best bang for the buck.....but it is very enjoyable. Bottom line is if you can get a SX-1250 that is complete, functioning as intended, and stock......well that's a steal and enjoy it. It will absolutely drive 2 pairs of speakers such as the 1250s for a good long listening period although as Rolf said it was not intended to. Switching off one pair for background listening is a very wise suggestion. Everyone who has responded has done so correctly and with the best imformation they have available for you. Not trying to sound like an ass but the L-100s have always been respected as a great marketing success for JBL and not much more than that. It's like seeing a great 27" CRT tv, then you get a great 56" HD DLP. the 27" don't look so good. No one will question your personal apprectiation for the L-100s. But please don't be offended by snide remarks about the L-100s (27" crt). :)

SEAWOLF97
10-29-2006, 06:07 PM
Edit: zilch is on my ignore list now, so no worries, I can't see his posts.

Not to flame you , Alex, but the above action is like shooting yourself in the foot (IMHO)

Zilch
10-29-2006, 06:13 PM
There's considerable forum history to this, for those who've never read it:


For the best and most amusing readings ever on the L100 search for Bo's ultimately triumphant L100 basher thread where he nearly got seared by the Hoards after being dunked then plucked masterfully by Macka and Don's billiant follow-up on the L100's history in the making...the full Monty...probably the best post on the Forums to date.


http://audioheritage.org/vbulletin/showthread.php?t=1286

http://audioheritage.org/vbulletin/showthread.php?t=1389

alexkerhead
10-29-2006, 07:24 PM
Posting this to bypass the Ignore filter -
Dang Alex - Zilch has a test bench and has post MANY MANY significant, informed charts and postings here based on ACTUAL TECHNICAL Testing - not just some ... "hmhmhmhmhmh danged L100s sound real hawt with that danged classic Pioneer sauce ..."

No offense man, but - you are a newby here compared to many of the folks here who have posted regular, repeatable, informed knowledge in this forum. Folks who have thousands of dollars of scopes, sig gens and test gear - they really do know what they are talking about.

L100s are nice speakers - but - read your history - it was a mass market speaker that had a big appeal in the college crowd mainly due to the bass boom it produced. It was NOT accurate, just popular. Boom boxes! Its well known info.

If you like em, thats great - lots of folks do - but they are not the be-all, end-all of JBL speakers, and, relative to many of the more high end speakers these folks are used to (L300s and the 4343/44/45 series), they indeed are crap. Just most folks are too nice to say so ...
And thats just comparing a few of the tons-better speakers from that era.

So - mind your manners and give Zilch some credit, hmm?
I don't wanto to hear about another one of the knowledgable folks here driven off by some overenthusiastic newcomer who thinks 100 or so posts and a few pairs of speakers makes him an authority.

READ a bit of the posts here and learn a lot! I have been curtious and respectful on these boards and prefer not to have my stuff I spent so much money on called crap, can you appreciate that?

Lets see, I spent $225 on the receiver, $200 for my first set of L100, and $150 for my second set. $575, that is a lot of money when you are my age getting through college.


I don't think I am an autority, and I certainly never thought my stereo was the end all be all, but the fact remains, I could be using some bose 301s and a sansui g-3000, which is a much worse combination than what I have.

I know all about the history of the L100, I have read most of the material on this entire website pertaining to the forementioned and other history.
If I disagree with what "experts" and rich folks say, that is my prerogative.

Amount of posts only means I haven't been a member of this board as long as zilch.

Ya know what my dream system is?
Paragon on Marantz tube monoblocks.
I don't prefer bassy systems, trust me on that one.

I owned a set of Cerwin Vegas, now those are some boomy and bassy speakers.:barf:

I use an equalizer to compensate for the rolloff on the high frequencies, zilch even helped me with that, of which I am glad, but it doesn't give him the right to call my stuff crap.

Nobody else on this board goes around calling other member's stuff crap, as far as I have seen.

I would love a set of L300s, I just cannot afford them, I wish people would take that into consideration.
I would even like a set of L65s, but I just cannot afford them. Too many people with too much money are collecting them and never using them, but since they have too much money, they end up buying them, instead of the poor guy like me who cannot compete with big money.

Seriously, give this some serious thought everyone before you go around hating on people's stuff.

SEAWOLF97
10-29-2006, 07:57 PM
this seems like a nice place to close off this thread ??:blah:

Zilch
10-29-2006, 08:01 PM
Look again.

I didn't call anything crap.

I just want you to stop insulting those who have invested the requisite effort to actually KNOW what they're posting about here with your gratuitous blather.... :mad:

alexkerhead
10-29-2006, 08:12 PM
Look again.

I didn't call anything crap.

I just want you to stop insulting those who have invested the requisite effort to actually KNOW what they're posting about here with your gratuitous blather.... :mad:

I decided to remove you from my ignore list for one reason, you do offer great information, but you did imply my stuff sounds like crap, which is saying it is crap. Only crap can sound like crap.


2) It most certainly sounds like crap.

Some people are touchy with their expensive stuff.
Although I know you have excessive cash to spend, I don't.

Storm
10-29-2006, 08:17 PM
My TWO Cents, but I wish I had more than that. :)

First of all, I am 22 and am still going through college and learning the ropes just like Alex.

I am fortunate to have a hobby - selling on eBay - that allows me to purchase the speakers I do have, Altec 846U's.

I agree with Alex - he could have bose or worse, give him credit where credit is due.

Zilch, I think sometimes your posts are only done so you can increase your post count.

BTW - how old are you Zilch? I am only asking so I can understand where you are coming from - the angle.

You older audio crowd should be happy that guys like Alex and I are finding this vintage hobby and prolonging the life of these vintage relics. We could easily have gotten into the shit that is mass produced nowadays.

Unlike Alex, I feel my ultimate system is complete. I am very fortunate - and yes, I wish some of these people with money would let some of us less fortunate to be able to afford such things, but that is life.

So, all in all...I am fortunate for Zilch, but at times Zilch - you get agressive and very rude. What the frick is the [....] at the end of almost every single post you write? - Those are incredibly annoying.

This is a great place to learn, but when people tell others what they think they should own and what should sound good, that is where it draws the line. Graphs are nice, but the human ear is a better measurement - everyone can agree on that.

Yes, I am sure graphs are informative, but why do you guys post so many? Just let your ears do the measuring....

Peace.

;)

Zilch
10-29-2006, 08:29 PM
I decided to remove you from my ignore list for one reason, you do offer great information, but you did imply my stuff sounds like crap, which is saying it is crap. Only crap can sound like crap.Fine. I just changed it....

alexkerhead
10-29-2006, 08:34 PM
Fine. I just changed it....
Also, I just noticed you posted my image on here, wow, that is really mature.:D

You also posted a pic of my project L100s(before baffle paint and new ports), thanks, I am quite happy with the way they turned out.:p

alexkerhead
10-29-2006, 08:37 PM
Now, apparently, you are also an expert on cabinet refinishing:

Do you believe for even a millisecond that you have ANY standing (see below) to advise on that subject in Technical Help, in the context of the expert work and experience of others (riessen, audiobeer, more...) here?

I WAS looking forward to you posting something that was actually correct in these forums.

Ain't gonna happen, obviously.... :(


I didn't see them respond to the thread, I always welcome correction to anything I type.

I do know how to veneer and refinish, many people do.

Feel free to jump in on that thread and correct me please.

Zilch
10-29-2006, 09:09 PM
It's not good enough we're discussing this via PM? You want to do this in public?

Fine with me:

YOU posted those here. It's not MY problem they're now an embarassment to you....

alexkerhead
10-29-2006, 09:12 PM
YOU posted those here. It's not MY problem they're now an embarassment to you....
Explain, how are they embarassing?

Robh3606
10-30-2006, 09:40 AM
I just closed this thread. If the 2 of you have an issue take it off line.

Rob:)

------

Yea, and I agree with Rob.

Let me double-close asking this - why do you CARE whether someone likes your stuff, or not? :dont-know


bo