Page 32 of 33 FirstFirst ... 2230313233 LastLast
Results 466 to 480 of 492

Thread: Bgw amp plus eq for free!

  1. #466
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    ANOTHER TOY TO PLAY WITH...

    While being at dealer's place for more Neutrik connectors and Rapco spkr cables, i purchased a used Direct Injection (DI) box. Dealer had an interesting model for cheap. Cosmetically it does show mileage, but everything used they sell goes first to repair tech dept for testing. There's various types and makers of DIs, Digiflex being a Canadian company i'd rather get one from them.

    For $15.CAD the DI is a pretty good deal, i probably have my money's worth or more just with the connectors on the unit. My interest was in getting a stereo one, not a more frequent mono. Its not the only stereo on the market, but others like Rapco or Radial Eng., more often have 1/4" inputs and XLR outputs. The Digiflex has two 1/4", one 1/8" stereo, and two gold plated RCA inputs, then XLR outputs, giving more input flexibility from various devices. This one could be more audiophile or playback oriented, than musician specific (still has 1/4" & XLR).

    It appears to be well made, built tough like most good DIs, the box connectors are protected, and its a relatively heavy unit at just over 1.25 LB. Approx dimensions are 5" L X 4" W X 2" H. The DI having rubber feet it won't scratch or slip on a surface, though one might use it vertically oriented on its side for space saving.

    According to Digiflex its made of high quality components and has Audiophile grade transformers. Haven't had time yet to try it. But it might become a lower cost, passive alternative to an Aphex 124A i use to balance turntable signal for e.g., or using a 1/8" stereo cable to feed my MD recorder in the DI then on to mixer, etc.

    Having checked this DSPDI carefully i'm not worried about the cosmetic, what matters most here is the connectors and the stuff inside that box, both of which are in good condition.

    BTW to all viewers here, i never expected this thread would ever reach a quarter-million views! Thank You. Have other things in the pipeline but not enough time these days, pretty busy for a while. So we'll see.

    Richard

    Name:  IMG_2987.jpg
Views: 256
Size:  65.5 KB

    Digiflex 2020 price list shown, DSPDI retail price now around $65.CAD

    Name:  IMG_2986.jpg
Views: 246
Size:  74.6 KB

  2. #467
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    Name:  IMG_2991.jpg
Views: 260
Size:  100.0 KB

    Rocker switch is for ground lift, if need be

    Name:  IMG_2993.jpg
Views: 249
Size:  117.3 KB

    Gold plating on RCAs is better seen at the bottom of this pic

    Name:  IMG_2996.jpg
Views: 257
Size:  78.2 KB

  3. #468
    Senior Member
    Join Date
    Aug 2017
    Location
    WDC USA
    Posts
    240
    Just keep in mind that a nominal -10dbm input on the 1/4" jack side of the DI will give you about a -40 dbm mic level XLR output side of the DI. Useful if you're feeding a recorder that has mic level inputs but not really a passive Aphex level convertor. Also those unshielded transformers don't want to be near any sort of power transformer.

    Quote Originally Posted by RMC View Post
    ANOTHER TOY TO PLAY WITH...

    ...
    According to Digiflex its made of high quality components and has Audiophile grade transformers. Haven't had time yet to try it. But it might become a lower cost, passive alternative to an Aphex 124A i use to balance turntable signal for e.g., or using a 1/8" stereo cable to feed my MD recorder in the DI then on to mixer, etc.

    ...

    Name:  IMG_2987.jpg
Views: 256
Size:  65.5 KB

    Digiflex 2020 price list shown, DSPDI retail price now around $65.CAD

    Name:  IMG_2986.jpg
Views: 246
Size:  74.6 KB

  4. #469
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    Hi Riley,

    Thanks for the output level reminder. However i don't anticipate any gain problem with the mixer XLR inputs. Mackie channel trim adjustment on XLR provides up to 60 db of gain. Then channel gain pot provides up to 20 db of gain. So there's a lot of gain in store, not counting the masters.

    Richard

    Mackie owner manual

    Name:  IMG_2998.jpg
Views: 240
Size:  100.4 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  5. #470
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    CREST AUDIO AMP MADE IT HOME TODAY

    Been looking at the small (1 RU) Crest Audio PA-150 Class A/B amp for some time. I don't really need it but its hard to say no to a good old Crest, made in the USA, not China. Looks in pretty good condition and was not abusively priced.

    Appears to be made tough and the little i could see inside seemed encouraging.

    Its quite heavy for its size, reminds me of the BGW 100Bs i had. But this Crest is about 20 years younger, and a more modern amp.

    I put the Crest on a scale and it showed about 17 lb, close to BGW 19 lb. Other small size amps i have (QSC, Tascam, etc.) weigh about 12 lb.

    Eager to hear how it sounds, though quite busy these days, hopefully will find some time to give it a good road test. Don't have time now for all the details but will be back later with more.

    Posting below the short features sheet at this time, and no you're not dyslexic if you read the amp provides the same 75W RMS at all impedances (4, 8, 16 ohm). Btw one shall NOT move the impedance selector at the back while the amp is on, it should be turned off (owner manual).

    Checking the amp upon getting it, it does turn-on so a good start, and i noticed a feature i don't recall being mentioned in the docs: seems to have turn-on delay and turn-off muting, which the BGW did not have...

    Small amp with a big heart, lol

    Richard

    CREST AUDIO PA-150 PROFESSIONAL AMPLIFIER COMMERCIAL SERIES.pdf
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  6. #471
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    Name:  IMG_3016.jpg
Views: 216
Size:  82.1 KBName:  IMG_3019.jpg
Views: 213
Size:  75.5 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  7. #472
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    Name:  IMG_3021.jpg
Views: 215
Size:  96.5 KBName:  IMG_3023.jpg
Views: 217
Size:  88.7 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  8. #473
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    The Crest Audio PA-150 is my first Crest and Commercial series amp also. I figured if that's what it takes to get a good used Crest amp then i'm game. Would not have purchased one from many other brands. Rear panel gain controls and barrier strip connections aren't really my cup of tea, but for this Crest amp its worth the compromise. Years ago a new PA-150 was a $595.US amp (retail) that some dealers discounted to $476. as i saw.

    The decision wasn't made in a hurry, did my homework. Then, getting a third party's feedback, specially from someone who repairs amps, could be helpful re reliability. So recently on my last visit to dealer i spoke with one of the senior repair technicians regarding the Crest inside story. He said we've been using Crest Audio amps for at least 20 years and they're not problematic amps (dealer also uses many Crown Macro-Tech and i-Tech type). Then he inquired about asking price and the unit's condition as seen on pics. Following my positive reply he said i wouldn't hesitate if i were you, go for it.

    Though getting the Crest amp means i bought myself a little work, connections wise. Had a few suitable cables i made in the past (1/4"TRS to barrier strip) however these are assigned to other equipment. I'm used to XLR and 1/4" TRS, as well as binding posts mated with banana plugs for speakers. Checked in my stuff and have all i need for the barrier strips wiring, with many different terminals. Simply needed to make new dedicated cable sets, with connectors and terminals to get going.

    For speaker wires i didn't want to cut some lengths now from my 12 and 14 gauge rolls that i may regret later having cut since i'm still in a temporary setup. Have a pair of 6-7 ft. 16 gauge cables that should do the job for amp testing purpose. I plan to use the largest terminals that will fit on the barrier strips, specially for speaker outputs, in order to minimize resistance and improving current flow to speakers.

    The Crest won't be in a permanent installation for a while, will rather be in my equipment rotation like others do. Commercial/installation gear can sometimes be out of direct sight, the operator not necessarily aware an amp is clipping. So the compression feature on this amp can be useful in preventing CD or tweeter burn-out for example. That feature seems quite logical and in line with the "set and forget" that commercial equipment often is. The show must go on...

    Have not shown pictures inside the amp, nor have i opened it yet, since seller put a sticker joining top and back panels to prevent amp tampering, because he provides a 30 day warranty/return privilege. If the seal is broken, then tough luck buddy. Therefore, after 30 days i'll be more than happy to remove the top cover, plus see among other things what makes it so heavy. Probably not the long heatsinks since these are Alu made, a relatively light metal. More coming.

    Richard

    P.S. Last night and again tonight spent hours listening to various CDs and LPs using the small Crest Audio amp. Sound is impressive, had not expected this much. It deserves to be on duty more often than its turn in my rotation: no days off! Will report on the listening tests in a coming post.

    Name:  IMG_3030.jpg
Views: 205
Size:  65.9 KBName:  IMG_3043.jpg
Views: 209
Size:  75.4 KBName:  IMG_3049.jpg
Views: 200
Size:  84.4 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  9. #474
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    CREST AUDIO AMP LISTENING TESTS

    Since my last post here, i did a third listening session with the Crest amp. The comments cover all three.

    This amp sounds really good. i was struck right at the beginning by the transparency and clean signal it offered in CD reproduction. Presence and detail are also nice. The mid and highs are possibly where it shines the most even though i found bass to be tight. The Crest beats the BGWs i had on sound, the latter having a more incisive top end for example. My Mosfet amps have a softer one, the Crest being in the middle with just the right highs. Globally one of my preferred sounding amp.

    In fact, being so transparent and clean i realized, looking at the output LEDs on the mixer, that i was turning up the master gain higher than usual, with consequent spl, and no listening annoyance. Seems easy to get ambitious on this amp's level. It was not due to amp gain requirements since it has the same (8 ohm) 1V RMS for full output spec, as other amps i have. While using the usual gear, the different component being the Crest amp.

    Using CDs i did note a little brightness, not to my liking, with the Tascam CD 200 SB player (balanced version). I don't recall having this with the other Tascam (CD 200 unbalanced) i have. To confirm if the amp or CD player was the cause, i switched to a consumer CD player i kept and played the same CDs with it. Didn't use the cheap RCA cables that come with these, but instead some nice Digiflex RCA, having twisted pair wires, with good connectors and RCA to 1/4" adaptors to connect in the same mixer channels (though unbalanced this time). No brightness heard at all with that player. Therefore the Crest amp is not the cause here, the balanced Tascam is. Solution is simple, high EQ (12 khz) on mixer at -2db or so gets rid of the brightness, peace restored. Apart from that brightness, the balanced Tascam sounds way better than the consumer player.

    With LPs (using Shure M95ED with an original stylus) the amp did not provide as nice sound as CDs, though results are still pretty good. I'd say the reward might be little less evident here. I think that with LPs one may forfeit some musical realism due to lower dynamic range available (higher noise floor). So the amp's potential sound appears to be program material quality dependant.

    The Crest remains a surprisingly well mannered PA amp, yes for a SR amp company, but no real surprise here when considering Crest previously indicated using computer matched pair of KEF 105 speakers in listening tests for products development. This is a good reference used in order to taylor their amps' sound.

    I'm pleased with the amp, it takes the program material you throw at it and reproduces such competently, which is basically what the job is. Btw when pushed somewhat (say 100 db spl peaks) the amp didn't get warm, although another amp was on top of it partially obstructing the radiators, it remained at room temperature. The compression feature did not activate and i didn't try to get it going, would be too loud level with boss at home...

    Installation gear is a little different world for amp connections, however it doesn't mean these come with poor sound, hell no.

    Richard
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  10. #475
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    I checked the grey twisted pair installation cable i used to connect signals to the Crest Audio amp and counted 10 wire twists per foot so shouldn't be a problem. Easy to identify on this type of cable, contrary to microphone type cables, since at every wire twist i can see and/or feel a small bump on the cable's jacket.

    Upon making these cable sets for the amp i did continuity tests on all and they were good. Even though they work fine i'm not really satisfied with the way i connected the drain wires used as circuit ground. Dumb me: two spade terminals on one input, and having their red plastic ring on, don't fit as nicely on the barrier strip screw for grounding, somewhat thick for the space, needing a little terminal bend.

    I can do better using terminals with no red plastic ring, as i have some, and install two of them thick behind the ground screw, but with their wire entry leg leaning a little to the left for one, and to the right for the other, these two making a slight "V" shape in the barrier strip. They'll fit more appropriately behind the single grounding screw for both channels. Will modify that connection when i get a chance. More later.

    Richard

    Name:  IMG_3060.jpg
Views: 181
Size:  74.5 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  11. #476
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    CREST AUDIO AMP INSIDE PICTURES

    As referred to previously, there ya go.

    The 30-day seller warranty/return privilege has expired. The 19 y.o. amp (2003) works well and sounds good so i kept it. I tested all three impedance settings (4, 8, 16 ohms) and they work fine. Turning off the amp, as recommended, before impedance switch changes to use different impedance speakers. I can also confirm it does have turn-on delay and turn-off muting, therefore no annoying noises heard during these steps, even with gain controls fully up, that's nice.

    Time was up to cut the seal on the amp and see what's in it, plus a possible explanation for the weight. What appears to justify the amp's heaviness is the pretty large toroidal transformer used vs amp size and the 75W RMS power rating. Transformer is about 7.5" diameter and 1.25" thick. The triangular bracket holding the transformer in place is an indirect proof that its heavy. Have not seen such on comparable amps in stock.

    Crest Audio has a reputation for overbuilt power supply. It seems to be true in the present case. Other similar size amps on-hand don't match these transformer dimensions, though the Mosfet amps for example have a little thicker one but a smaller diameter.

    The output devices are directly mounted on each heatsink, four devices per side (plus a temp sensor), coming from Toshiba Japan, and producing very little heat in my tests so effective convection cooling. That's a good thing since it is often said that heat is the enemy of electronic components. Other small size amps i own show more often having two output devices per side. As for the storage capacitors its written on them Nippon Chemi-Con so presumably Japanese too.

    Btw one has to be careful before purchasing this amp (or other Crest), since Peavey purchased Crest Audio in 1999 (late in year according to some). Crest business continued for a while but was eventually made part of Peavey. In my view this raises a question regarding amp quality, i.e. was a particular unit made by Crest or by Peavey? There's an unknown manufacturing switch date. For various reasons i'm confident that mine was made at the Crest factory in the USA.

    I have nothing in particular against Peavey, but i didn't want a Peavey amp, rather a Crest Audio one simply because i think Crest made better amps. Later Peavey integrated Crest Audio in their Commercial Audio division, therefore these became Peavey made amps. Plus the possibility that some be made in low-cost China for Peavey since this being the general trend in audio.

    There are some signs or clues when trying to differentiate a Crest made amp from a Peavey one, specially useful around the transition period between the two.

    Finally, Crest made amplifiers for others too: like Clair Brothers Audio; also in cooperation with Meyer Sound for systems used in Europe; even for Peavey, their ips 150 being similar to the Crest PA-150 i have. More later.

    Richard

    Name:  IMG_3062.jpg
Views: 142
Size:  103.8 KBName:  IMG_3070.jpg
Views: 142
Size:  93.6 KBName:  IMG_3076.jpg
Views: 142
Size:  108.2 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  12. #477
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    A USEFUL PIECE OF INFORMATION

    I've been using Caig's Deoxit Fader F5 for years in order to clean static noise on pots for example. This with more or less success, depending on gear, since static noise eventually comes back, sometimes sooner than later. I know other guys here also use Caig's F5.

    Recently i had it with noise coming back, so on my last visit to dealer i brought with me the Mackie mixer to have the first four channel gain pots (mic/line) replaced hoping to get some more years of silence. Long story short, the senior repair tech told me i'd hate to have to charge you $300-400. to replace these (labor, parts and taxes). I said i'll pay it this small mixer is just too useful to me as a "control center". He went to check in his computer and came back with bad news: all VLZ series mixer pots were discontinued...

    I told him i used Caig's F5 in the past but it hasn't been a lasting solution. These pots are sealed and the easy way to try to clean them is to remove the knobs and spray in the tiny cavity around the pot's shaft, hoping it will work. However, most interesting was the tech's comment about Fader F5: F5 is ok but we prefer to use Caig's F100. (these techs don't usually work on consumer gear, only Pro stuff, many being quite expensive units; they're not a cheap shop but at least they know their knee from their elbow, with mostly 20-30 years of service techs).

    He didn't explain their F100 preference but i might have found the reason. I had a quick look at Caig's F5 and F100 data sheets and in the formulation it says F5 has only 5% Deoxit while the F100 has 20% Deoxit, four times more. Probably better cleaning power, F5 might be too mild in some situations. I figure senior repair techs have tried a lot of things over the years and probably know what works better or less so.

    The tech offered me, free of charge, to spray a number of channel gain pots with Caig's F100, offer accepted, and using the same method as mine. Got home tried it, channel 1 static at 8-9 o'clock still there and channel 2 static around 12 o'clock remained there too, though the knobs were exercised. About a week later time to use mixer again, surprisingly no static noise on the pots sprayed!!

    Well, i doubt the pots have self-repaired themselves. I figure that after a while some F100 Deoxit found its way inside the pots these not being perfectly sealed? Its the only explanation i can think of. So far so good and it didn't cost me a dime. Next static noise issue i'll simply get a can of F100 like the pros use as this might increase my luck...

    Richard

    Name:  IMG_3081.jpg
Views: 122
Size:  81.6 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  13. #478
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    PRECISION REGARDING TERMINALS FOR CREST AMP BARRIER STRIP

    On post # 475 i showed a pic of two spade terminals making a "V" shape for barrier strip connection. This should be considered as an example only, as the particular terminals shown are too large to fit in there.

    I did change the terminals for the two input grounding wires going to the single ground screw. Trying a few different ones i settled for narrower spade terminals # 22-16 as these allowed a correct "V" shape placement in the barrier strip, as long as their red plastic ring is removed.

    The little exposed drain wires are now covered with heat shrink tubing, instead of the previous cable jacket pieces which also worked. This connection is circuit ground and you don't want an exposed nude drain wire to touch the amp's metal case (having chassis ground). Mixing the grounds is an invitation for ground loops noise issues. Keeping them separate or isolated from each other means peace. Proof: with full gain and my ear on the speakers all i can hear is a tiny little ssss sound, no hum.

    Checking continuity, as well as total resistance, of the 6 ft. installation cables (post # 473, 2nd pic) having a connector at mixer end and terminal at amp input was done with a precise multimeter, i got 0.1 ohm (meter residual is 0.0 to 0.1 ohm), so not enough resistance here to call mother...

    Small solid copper wires circled around the grounding screw would probably do the job too, avoiding terminal use. Although telephone type wires might come to mind it seems too small size for me, i'd rather use something in the 20-24 AWG range to minimize possible losses due to resistance of an overly small wiring. Hence the use of twisted pair 22 AWG cable in that specific case.

    Richard

    Name:  IMG_3094.jpg
Views: 97
Size:  77.4 KBName:  IMG_3096.jpg
Views: 97
Size:  69.3 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  14. #479
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    RE post # 469

    I realized that i forgot to post a pic in relation to Mackie mixer gain. My answer to Riley in that post showed or mentioned gain available for the trim and channel gain adjustments, not counting the master level adjustment for which i had a picture that wasn't posted. Better late than never.

    Pic is clear enough to be enlarged, the fact its horizontal, not vertical, is not an accident, it looks better this way and the top where the LEDs are gives a preview of the master pot gain structure (on pic top right is the master gain control and just under is the headphones or control room pot for amp and monitors. Instead of being wasted muted channel(s) can also be sent to Alt 3-4 bus for output connection using an amp and spealers. This is in addition to the main outputs on either XLR or 1/4"TRS. Since the main out XLRs have switchable level (+4dbu or mic level) this mixer can easily be used as a sub-mixer to a larger one if need be. Many possibilities.

    As can be seen on the first three rows of LEDs its 10 db per row, initially going up quite rapidly, after it slows down to 3 db for two rows, then a few 2 db increments, etc. In actual use i can't recall ever turning-on the yellow and red LEDs. The 28dbu clipping applies to the XLR outputs whereas its 22dbu for all other outputs including for main out on 1/4"TRS. For single amp use, and considering my amps usually require about 1 volt for full output, then level wise i tend to hang around in the first half of the LEDs metering.

    So there's a fair amount of juice available here for a number of outputs.

    Richard

    Name:  IMG_3055.jpg
Views: 92
Size:  112.2 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

  15. #480
    Senior Member RMC's Avatar
    Join Date
    Feb 2017
    Location
    Canada
    Posts
    1,405
    SMALL SIZE POWER AMP SEARCH

    Had a draft of this post in the computer for a while. It was intended to be the first Crest amp post, but turns out to be the last....

    Before settling for the small Crest Audio amp i looked at a number of contestants in that group from some of the big names in the Pro power business, as i wanted to add another to those i already have. There's certainly fewer models today than in the past, a good reason to look at used ones. That Crest didn't show up a lot on the resale market compared to Crown for example.

    Amp wise, no think big for me, since i don't need 125 db to be happy music wise, plus i value my hearing, then smaller size amps make sense and offer me more versatility/flexibility. Still prefer owning a number of quality small amps than just a few large ones. If need be, with the right choices, small amps may become mid-size ones when bridged, with power in the 150-300W range for some of them.

    Sorry uncle Crown, but others are ahead of you in this race. The small D series amps, D-45/D-75/A, can put their clothes back on, they have less to show vs some of the competition (except for reliability which i also value). They seem like older amps being carried on and on for years. Crown appeared to be snoozing while others were working on developing more recent designs (e.g. BGW, Crest, QSC, Yamaha; the Ashly being a little more recent).

    D-45 doesn't have a 4 ohm FTC power rating. I assume it was mostly intended to power high efficiency HF devices having 8 or 16 ohms, such as JBL 2402/2405. Brother D-75/A power output remains somewhat low for the class. I guess the aim here was to power MF/HF horns, maybe Klipschorns with 105 db sensitivity, or similar stuff?

    Crown used great imagination in trying to make these appear more powerful, including put forward their 1 khz power ratings early in the manual. One needs to go near the end to learn the actual power story. Crest also used the 1khz technique for Crown comparison, though they did on the same page, one rating just under the other, and showing better numbers. D-75 is still a 35W amp FTC 8 ohms, the Crest having double that power for 3 db more output or headroom.

    The single rack space CREST AUDIO or QSC 1100 for example are more modern than Crown's aging D-45/D-75 small amps of similar era. That QSC being better equipped than most comparable amps in the versatility department, while being reliable.

    Features the QSC has but many others don't (at all or partly):

    8/4/2 ohm power ratings (a few seen indicated being stable down to 2 ohms but they didn't have a 2 ohm power rating); 2 db Dynamic Headroom @8 ohms, (2.3 db @ 4 ohms, owner manual), 2 db headroom being equivalent to 1.6 times the power ratings for 4 and 8 ohms; turn-on delay and instant-off muting meaning no on/off noise; higher slew rate; recessed front panel for protection; 20 hz high-pass filter (owner manual); front panel circuit breaker, no damn fuse!; 8 DIP switches at the back for simple amp configuration and octal sockets accessories (crossovers, limiters, etc.); barrier strip, 1/4"TRS and XLR connectors (Switchcraft); 5-way binding posts. This didn't come cheap, 1991 Can retail was $895., paid about $700. for each. I guess it might have been $600. in the US.

    The 1990 version of D-75 had XLRs, 1/4" TS unbalanced inputs and binding posts speaker outputs. For the 1999 D-75A revision they made cosmetic changes updating the look to match other D series II amps. Moreover, other apparent things changed: Combi XLR/1/4" TRS connectors on inputs, barrier strip for speaker outputs, maybe to cut costs or they decided to make the amp an installation type, borrowing the barrier strip idea from Crown's Com-Tech series? D45/D75/A appear to be light weights in that class with 8+ and 9+ LB contrary to others, and their slew-rate seems pretty low vs competitors.

    BGW 150

    Successor to model 100Bs i had, similar power ratings, updated transformer to toroidal, heatsink now along each side like the Crest has, different storage caps, some things moved around inside, etc., not very different from the 100B, doesn't appear to have turn-on delay/turn-off muting, however amp weight went down from 19 to 14 lbs.

    BGW 200

    Later 90's BGW released model 200 to replace the 150, it has some more 8 ohm power, however no meaningful 4 ohm rating (only limited IHF music power rated, no FTC) pretty surprising from this company and different from model 150, but this 200 has turn-on delay (off muting??) and a nice slew rate. Same weight as the previous one. Somewhat of a disappointment in my view for a $999.US retail, would have expected a little better from BGW. If i didn't previously owned the 100Bs, might have considered getting a model 150, not the 200 though.

    The Crest can maintain its 75W RMS/cha. with 4-16 ohm impedances, has an interesting peak compression feature at the onset of clipping, no user intervention required, on/off muting, good slew rate, etc. In the above context voting for the Crest wasn't a difficult decision to make...

    Note there's a typo on the Crest PA-150 tech sheet regarding frequency response: +/- 1 db for 10hz to 40khz is correct, but the +/- 2 db from 20hz to 20khz is wrong, its 0.2 db 20hz to 20khz, which makes more sense in view of the previous bandwidth (wider bandwidth larger tolerance, narrower bandwidth smaller tolerance). Plus the Architec's and Engineer's specifications at the bottom of tech sheet indicate 0.2 db in that case.

    Richard

    CREST AUDIO PA 150 AMP SPEC SHEET.pdf

    Name:  IMG_2916.jpg
Views: 68
Size:  107.6 KBName:  IMG_2885.jpg
Views: 67
Size:  93.9 KB
    POWERED BY: QSC, Ashly, Tascam, Rolls Mosfet, NAD, and Crest Audio

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Free and new to me!!
    By mrbyl in forum Lansing Product General Information
    Replies: 4
    Last Post: 06-05-2010, 12:21 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •