Urei 6230 THD

[Val]

I am collecting amps to tri-amp my LE15A/375/075 rig. A friend said he had a Urei 6320 I could have for $150. The price seems ok and is aligned with my budget (and it's super clean). Looking at the manual I see that the max THD from any power level is less than 0.1%. That doesn't seem great. I would use the 6320 to power the 375 and would be running it way under it's max. Is JBL just being conservative?


http://www.jblproservice.com/pdf/Vintage%20JBL-UREI%20Electronics/JBL-6230_%206260manual.pdf

[hjames]

I am collecting amps to tri-amp my LE15A/375/075 rig. A friend said he had a Urei 6320 I could have for $150. The price seems ok and is aligned with my budget (and it's super clean). Looking at the manual I see that the max THD from any power level is less than 0.1%. That doesn't seem great. I would use the 6320 to power the 375 and would be running it way under it's max. Is JBL just being conservative?


http://www.jblproservice.com/pdf/Vintage%20JBL-UREI%20Electronics/JBL-6230_%206260manual.pdf

I ran a pair of biamped 4341s with a JBL/UREI crossover and used a 6260 for the 2235 woofers, and used a 6230 for the
high split (2122 midbass, LE85 horns, 2405 slots). We never played stupid loud in our system either.

I suspect the specs are conservative - tho they ARE pretty old amps now and
without having a trusted shop go through them completely, certainly aren't running as they did new.

It was great as a budget approach, tho I did later replace the JBL amps with a pair of Adcom GFA555 (1st gen),
and these days I am running a B&K ST202plus amp on the speakers that live in that space now.

[Mr. Widget]

Looking at the manual I see that the max THD from any power level is less than 0.1%. That doesn't seem great... Is JBL just being conservative?Just my opinion, but I think that THD and IM specs are pretty close to irrelevant. I wouldn't obsess on damping factor specs either.


Widget

[Val]

Just my opinion, but I think that THD and IM specs are pretty close to irrelevant. I wouldn't obsess on damping factor specs either.


Widget

I'd like to hear more about this. Are there certain specs you pay attention to?

[Mr. Widget]

Are there certain specs you pay attention to?Not really. In general I judge the power supply capacity by comparing it's 8 ohm and 4 ohm capabilities, but really there is no substitute to actual listening tests.


Widget

[grumpy]

Noise (esp with higher sensitivity speaker), current capability, low output impedance (more important with speakers that have large impedance variations over freq), low distortion at lower power levels (not normally specified), I actually like looking at IM (can give an idea of how linear the amp is before feedback is applied)... :blah: Looks, connectors, fan required?, reputation...

Used to look at watts/lb ... Lower being "better" :) ... When there was a large difference in the value for a wattage rating, something funny was going on (D, G, H class or overenthusiastic marketing). Not so useful these days.

6230/60 are good amps, if they have not been abused.

[rockin'rushmore]

How does one abuse a amp?I picked up a 6260 ,think it was out of a theater,not too rashed up.I like to jam out at times,thing has some fantastic "grunt"would not want to hurt it.So what would be detrimental to the life of a amp?:confused:

[grumpy]

Heat/lack of adequate ventilation.

weather.

dropping it

shorting the output, or nearly so (improper load)

extended clipping sessions.

running from improper ac voltage.

...

did I mention heat ?

[Val]

I picked up the amp and my friend was willing to let me try-before-buy:bouncy:. Good thing too:no:.

I auditioned the amp in the living room on a small test speaker I didn't care about, then my LE15A/375/075 rig, then in the garage on the my 4699 Cabaret. This amp is in great shape. Totally heavy duty construction. Fan-less. I thought the LE15's did exceptionally well with this amp on the low end. Not so shimmery on the high end as the in-built amps in my Integra AVR. The downfall of this amp is noise. With no input connected and the gain cranked there is noticeable hiss. With input connected but not delivering signal still noticeable hiss. I'm guessing that it has to do with this amps age as I doubt this amp had this problem when is rolled off the assembly line.

I appreciate the feedback from Grumpy, HJames and Mr. Widget. I'm giving this amp back to my friend. I now have a better idea on how to evaluate a power amp. Thank you.

[grumpy]

Might give it a try with the gain turned down some. Probably don't need to run it wide open. Need to ~match the gain of other amps used to compare.

[Val]

Might give it a try with the gain turned down some. Probably don't need to run it wide open. Need to ~match the gain of other amps used to compare.

Good idea. Tried it and the noise diminished to an acceptable level.

[ngccglp]

There is a local ex-JBL dealer clearing stocks and I took a chance on the 6230. It is NOS.

I took one unit home, hook it up to my 4345 passive, and I was blown away by the quality of the sound. I am currently using Mcintosh MC2500 which is no slouch. The 6230 is only 75W and my 2500 is 500W. I tried to find fault with the 6230 ... I really did... I cranked it up, expect it to fall apart musically, but song after song it just boogied along, and the bass on this thing is outstanding. The bass rattled my windows and ceiling. 75W !!! On the 4345, the highs are nicely extended, not what I expected from a pro amp.

Needless to say, I went back to the dealer and bought the remaining two sets. Too bad they only had 6230.

[Val]

There is a local ex-JBL dealer clearing stocks and I took a chance on the 6230. It is NOS.

I took one unit home, hook it up to my 4345 passive, and I was blown away by the quality of the sound. I am currently using Mcintosh MC2500 which is no slouch. The 6230 is only 75W and my 2500 is 500W. I tried to find fault with the 6230 ... I really did... I cranked it up, expect it to fall apart musically, but song after song it just boogied along, and the bass on this thing is outstanding. The bass rattled my windows and ceiling. 75W !!! On the 4345, the highs are nicely extended, not what I expected from a pro amp.

Needless to say, I went back to the dealer and bought the remaining two sets. Too bad they only had 6230.

Good to hear. I plan to use my 6230 for driving the LE15A's in this winter's tri-amp project.

[hjames]

The first version of my biamped 4341s used a JBL/UREI M552 active crossover, a 6230 for the high split and a 6260 amp for the low split.
I quickly swapped that for an Ashly XR-1001 which was much quieter and seemed to perform better than the M552.


There is a local ex-JBL dealer clearing stocks and I took a chance on the 6230. It is NOS.

I took one unit home, hook it up to my 4345 passive, and I was blown away by the quality of the sound. I am currently using Mcintosh MC2500 which is no slouch. The 6230 is only 75W and my 2500 is 500W. I tried to find fault with the 6230 ... I really did... I cranked it up, expect it to fall apart musically, but song after song it just boogied along, and the bass on this thing is outstanding. The bass rattled my windows and ceiling. 75W !!! On the 4345, the highs are nicely extended, not what I expected from a pro amp.

Needless to say, I went back to the dealer and bought the remaining two sets. Too bad they only had 6230.

[ngccglp]

Hi

After hearing the 6230 I will definitely look out for a 6260 to biamp the 2245H.

I am using 5235 with 4345 cards so far it sounds good. I also have a Ashly which I think sounds fantastic for the price.

[grumpy]

shoot. go for a 6260/side and bridge them (600w per 2245) :)

[ngccglp]

:applaud::D

[danielaam]

This series is great.

[ngccglp]

Hi,

thought i I would provide an update on my experiments with the humble 6230. I tried to use 3 units on a tri amp configuration. After some extended listening, I felt the bass, while extended, lacks the impact that I was used to with the HK 1.5 signature. So I decided to run a pair in bridged mode, which turns them into 300w mono amplifiers. What a difference. It's not just the extra power, but the overall characteristics of the sound changed, it has a lot more grunt and slam than my HK which is rated at 200w.

great stuff.

[Doctor_Electron]

On the 4345, the highs are nicely extended, not what I expected from a pro amp.

I do not understand why it seems often to be assumed that "professional" power amps do not produce excellent sonics. Perhaps a throwback to the past? Crown amps of many models are well regarded.

I had an Alesis Matica 500 made ca. 1994, which I (of course) regret losing to thievery. It was rated at 145 W continuous per channel @ 8 ohms and 80 volts/microsecond, with bipolar transistors in the output stages.

It was used to power a pair of 4410 monitors above 125 Hz, with two 2235 subs handling 125 Hz and below.

That amp was one of the two best sounding amps, always with JBL pro monitors, that (of too many) I have owned.

As essentially stated in the quote, one must judge a piece of gear by it sound, rather than specs or intended market.

"Sounds" like your JBL/UREI will be fine in your system. -"DE"

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